CN105164282A

CN105164282A - Steel product and method of producing the product

Info

Publication number: CN105164282A
Application number: CN201480020343.2A
Authority: CN
Inventors: 格雷姆·麦格雷戈
Original assignee: OneSteel Reinforcing Pty Ltd
Current assignee: Inverbi Construction Technology Co., Ltd
Priority date: 2013-04-13
Filing date: 2014-04-13
Publication date: 2015-12-16
Anticipated expiration: 2034-04-13
Also published as: AU2021202437A1; NZ712644A; WO2014165934A1; JP2016517915A; BR112015025895A2; AU2013205082B2; CA2908922A1; SG11201507872VA; KR102427244B1; AU2013205082A1; US20160068925A1; JP2019178424A; EP2984190A1; EP2984190A4; AU2014252700A1; KR20150140740A; AU2019201022B2; CN105164282B; AU2019201022A1; CN110331346A

Abstract

A method of producing a steel product includes heat treating a mechanically worked steel product and maintaining or increasing the ductility and maintaining or increasing the yield stress of the steel. A mechanically worked and heat treated steel product made by the method.

Description

Steel work and produce the method for this steel work

The present invention relates to the steel work for digging up mine, building and in general manufacturing.

The invention still further relates to the method for producing this steel work.

Described steel can be following any one: soft steel, medium carbon steel and Hi-Stren steel (it is also described to non-hardened and tempered steel in steel industry).

In this article, term " soft steel " is understood as that and means such steel, and it comprises: wt.% (mass percent) is the C of 3%; Other elements of this steel are added into, as Si and Mn as extra Addition ofelements (deliberateadditions); Residual/incidental impurities; And all the other compositions (balance) Fe.

In this article, term " medium carbon steel " is understood as that and means such steel, and it comprises: wt.% is the C of 0.3-2.0%; Other elements of this steel are added into, as Si and Mn as extra Addition ofelements; Residual/incidental impurities; And all the other compositions Fe.

Term " residual/incidental impurities " comprises can the element that exists of very little content, and as Cu, Sn, Mo, Al, Zn, Ni and Cr, the existence of these elements unprovoked specifically add these elements, but because of the steel process actual processed of standard.Such as, the existence of these elements can be because use steel scrap to come production Hi-Stren steel, soft steel and medium carbon steel.

In this article, term " Hi-Stren steel " is understood as that and means such steel, and it has following in the usual composition of wt.%:

C：0.07-0.30％；

Si:0.9% or less;

Mn:2.0% or less;

Mo:0.35% or less;

Ti:0.1% or less;

V:0.1% or less;

Nb:0.1% or less;

Cu:0.1% or less;

N:0.02% or less;

S:0.05% or less;

Al:0.05% or less;

Residual/incidental impurities: 1.0% or less; And

Fe: all the other compositions.

Term " residual/incidental impurities " under Hi-Stren steel linguistic context should be understood as that relevant to soft steel and medium carbon steel as described above.The content of element above in list as Cu and Mo is overall content, and namely these elements are as the overall content of extra Addition ofelements with residual/incidental impurities.

Described steel work can be any applicable goods.

Described steel work can be wire rod, pole stock, bar or band.

Described steel work can be by the steel work form that in wire rod, pole stock, bar and band, any one is made.

Described steel work can comprise any goods, includes but not limited to: for the reinforcing bar of concrete construction; For the reinforcing mat (reinforcementmesh) of concrete construction and mineral industry, it is made by being welded together with isolated parallel intersection wire rod by isolated parallel straight line material; The pipe be made up of steel band; For the connecting parts that any long products is linked together as reinforcing bar; Continuous helical material; For the binding (ligature) of Steel Reinforcement Cage, this Steel Reinforcement Cage is used for concrete column and beams of concrete; The fastening piece (comprising screw, bolt etc.) be made up of Steel Bar; The anchor pole be made up of Steel Bar; And for tension in concrete construction, building, mining or manufacturing or pressurized or to be cut or by other curved steel work.

The present invention is based on following important discovery: can by machined (such as, as carried out cold-forming by cold rolling) steel carry out heating the process (hereinafter referred to as " thermal treatment ") of carrying out this steel and can: (a) keeps or increases the plasticity of this steel (such as, this plasticity is measured with unit elongation, and be described about during unit elongation in the description, and call with term Agt (uniform elongation) when mentioning and strengthening steel, and be typically expressed as Agt _(-0.5%)); B () keeps or increases the yielding stress (YS) (for reinforcement steel, being typically expressed as proof stress (PS)) of this steel; And (C) keeps or increases the tensile strength (TS) of this steel.This is an important discovery, because metallurgy instruction: heat-treat the steel through mechanical workout, causes that the plasticity of this steel increases, yielding stress reduces and tensile strength reduction.

Such as, applicant finds: steel is through mechanical workout, and cross-sectional area reduces 5-30%, and cross-sectional area reduces to reach 75% in some cases; Then, under temperature range is 150-750 DEG C and the hold-time is the condition of 1 minute to 16 hours, this steel is heat-treated; In many cases, the Plastic phase of generation, for the plasticity of the steel through mechanical workout, increase at least 25%, and the yielding stress produced is relative to the yielding stress of the steel through mechanical workout, is increased at least 5%.

Generally speaking, applicant finds: with higher temperature and shorter time, or with lower temperature and longer time, can heat-treat the steel through mechanical workout, keep or increase plasticity, yielding stress and tensile strength.

It should be noted, the present invention is not limited to the mechanical workout changing charging steel or steel work cross-sectional area, but also may extend to the situation that cold working changes this charging steel or steel work shape.

Usually, when not limiting the scope of the invention, the chemical constitution of concrete steel, operational path and characteristic are summarized in following table.

Pay special attention to: in upper table, alleged " HT " means " thermal treatment ".

The present invention is based on deep R&D work, it is mainly tested the soft steel of a great deal of, medium carbon steel and Hi-Stren steel sample.These samples comprise mechanical workout under different condition and with differing temps and the heat treated sample of different time.By in the further part of specification sheets, described R&D work is discussed in more detail.

The invention provides a kind of method of producing steel work, the method comprises heat-treats the steel work through mechanical workout, and keeps or increase the plasticity of steel and the yielding stress of maintenance or increase steel.

Present invention also offers a kind of method of producing steel work, the method comprises heat-treats the steel work through mechanical workout, and keeps or increase plasticity, the maintenance of steel or increase the yielding stress of steel and keep or increase the tensile strength of steel.

The present invention also comprises a kind of through mechanical workout and heat treated steel work.This steel work can be any one in above-mentioned steel work, i.e. wire rod, pole stock, bar or band, and this steel work can be by wire rod, pole stock, bar and band any one make and comprise any steel work of above-mentioned concrete goods.

By the present invention, same starting material can being used, as Hi-Stren steel, soft steel and medium carbon steel, and by suitably selecting mechanical workout, heat treatment time and thermal treatment temp, required various mechanical characteristicies can be produced.

At this point, present invention also offers a kind of method of producing steel work, it comprises: for steel work is selected as raw-material charging steel; Select the mechanical workout of charging steel or the steel work be made up of charging steel, heat treatment time and temperature condition of heat treatment, thus provide required mechanical characteristics for steel work; Perform mechanical workout and heat treatment step, and keep or increase the plasticity of steel and the yielding stress of maintenance or increase steel; And produce the steel work with required mechanical characteristics.

By the present invention, a small amount of or a large amount of ready-made steel can be used to manufacture:

A () has bar, pole stock, wire rod or the net of high strength (such as, yielding stress >750MPa) and high-ductility (such as, uniform elongation Agt>1.5%); And

B () has bar, pole stock, wire rod or the net of middle intensity (such as, yielding stress >500MPa) and high-ductility (such as, uniform elongation Agt>1.5%).

Such as, performance is identical when tension, compare the reinforcement steel of usual 500MPa yielding stress, the material economy of 33% can be brought according to the steel of 750MPa yielding stress type (a) of the present invention.Therefore, when same performance, the diameter strengthening steel such as can be decreased to about 9.8mm from 12mm.Or employing diameter is 12mm and the bar that yielding stress is 750MPa can make performance improve 50%, thus such as when same steel consumption, can obtain the better concrete column of performance or beams of concrete.In identical performance and when benefiting corresponding occupational health and safety (goods namely processed are lighter), be made up of the material with identical characteristics and the net being applied to mining can bring at least 30% material economy.Can also increase plasticity is also a kind of possibility benefit, although very unimportant.

In addition, such as, in concrete construction industry, the net of the 500MPa of Agt>5% can be manufactured, make the steel consumption required by this application scenario requiring moment to reallocate of such as suspended floor reduce about 20%.The steel of present Australia is fixedly charged with valuation per ton ($/tonne) rate, therefore by reducing the consumption of steel to be fixed, can reduce the installation cost of reinforcement significantly.For the reinforcement of high strength bar or wire rod, equally also there is this cost reducing effect.

In addition, such as, by adopting high-tensile (yielding stress be 650MPa or larger) the toughness net manufactured by this way, the steel consumption needed for such as strengthening ground concrete slab or promotion (tilt-up) concrete product can be made to reduce about 20-25%.

The goods of these high-tensiles above-mentioned or middle tensile strength each all there is such attendant advantages: the implicit energy (greenhouse gases) in goods can be reduced significantly, and the concrete that may reduce post and beam uses, and along with reducing transport and other materials handling cost.

Unit elongation is the measurement of plasticity.In this article, unit elongation is expressed as uniform elongation---Agt.Term " uniform elongation " is interpreted as the measurement of the ability of steel being carried out before reaching its maximum tensile strength to elasticity and viscous deformation in this article.The numerical quantities of the unit elongation recorded in the description is, steel is after reaching its maximum tensile strength and then falling back to 99.5% of this maximum tensile strength, measured with the steel unit elongation of percentages, is expressed as Agt _(-0.5%).Use the method, the reliability measured can be guaranteed.Overall unit elongation is also used as the measurement of the plasticity of steel work, the especially measurement of the plasticity of steel plate.

Relative to the unit elongation of the steel through mechanical workout, the unit elongation through heat treated steel can increase above 5%.

Unit elongation through heat treated steel can increase above 10%.

Unit elongation through heat treated steel can increase above 15%.

Unit elongation through heat treated steel can increase above 20%.

Unit elongation through heat treated steel can increase above 30%.

Unit elongation through heat treated steel can increase above 50%.

Unit elongation through heat treated steel can increase above 100%.

Unit elongation through heat treated steel can increase above 150%.

Unit elongation through heat treated steel can increase above 200%.

Relative to the yielding stress of the steel through mechanical workout, the yielding stress through heat treated steel can increase above 5%.

Yielding stress through heat treated steel can increase above 10%.

Yielding stress through heat treated steel can increase above 15%.

Yielding stress through heat treated steel can increase above 20%.

Yielding stress through heat treated steel can increase above 30%.

Yielding stress through heat treated steel can increase above 40%.

Heat treatment step can be performed with any applicable temperature.There is several factors, all may have an impact to the selection of thermal treatment temp under stable condition to any.A factor is heat treatment time.Applicant also finds that often kind of thermal treatment temp all has time window, and in this time window, yielding stress and plasticity increase to the level higher than expecting minimum value.This window increases along with thermal treatment temp and narrows.Another factor is steel product ingredient.Another factor is target property, as plasticity and yielding stress.

Heat treatment step can be performed with the temperature of the austenitizing temperature lower than steel.It should be noted that, in any given situation, the actual temperature of steel in heat treatment process will be Time-temperature dependence and depend on steel product ingredient.Therefore, the temperature of heat treatment furnace can higher than the austenitizing temperature of steel.

Heat treatment step can be performed with the temperature lower than 1000 DEG C.

Heat treatment step can be performed with the temperature lower than 800 DEG C.

Heat treatment step can be performed with the temperature lower than 750 DEG C.

Heat treatment step can be performed with the temperature lower than 700 DEG C.

Heat treatment step can be performed with the temperature lower than 600 DEG C.

Heat treatment step can be performed with the temperature lower than 550 DEG C.

Heat treatment step can be performed with the temperature lower than 500 DEG C.

Heat treatment step can be performed with the temperature lower than 450 DEG C.

Heat treatment step can be performed with the temperature lower than 400 DEG C.

Heat treatment step can be performed with the temperature lower than 300 DEG C.

Heat treatment step can be performed with the temperature lower than 250 DEG C.

Heat treatment step can be performed with the temperature lower than 200 DEG C.

Heat treatment step can be performed with the temperature lower than 150 DEG C.

If be chosen as by heat treatment time enough short thus keep relative to the initial value of yielding stress, tensile strength and plasticity or increase yielding stress and maintenance or increase plasticity, so heat treatment step can be performed with the temperature of the austenitizing temperature higher than steel.

Heat treatment step any suitable time can be performed.There is several factors, all may have an impact to the selection of heat treatment time.As have above about thermal treatment temp discussed, these factors comprise thermal treatment temp, steel product ingredient, target property and productivity.

Heat treatment step can be performed and be less than 16 hours.

Heat treatment step can be performed and be less than 10 hours.

Heat treatment step can be performed and be less than 6 hours.

Heat treatment step can be performed and be less than 5 hours.

Heat treatment step can be performed and be less than 4 hours.

Heat treatment step can be performed and be greater than 1 hour.

Heat treatment step can be performed and be greater than 45 minutes.

Heat treatment step can be performed and be greater than 30 minutes.

Heat treatment step can be performed and be greater than 10 minutes.

Heat treatment step can be performed and be greater than 5 minutes.

Heat treatment step can be performed and be greater than 1 minute.

Heat treatment step can be performed and be greater than 30 seconds.

Heat treatment step can be performed under any applicable atmosphere.Atmosphere can be oxidizing atmosphere or reducing atmosphere.For concreteness, heat treatment step can be performed in atmosphere.

Heat treatment step can be performed when there is no protective atmosphere.This is considerable advantage of the present invention.

Heat treatment step can be performed by using any applicable means.Particularly, any applicable heat energy can be used to perform thermal treatment.

Through the goods that the steel work of mechanical workout can be any applicable form.Can be any one form of wire rod, pole stock, bar or band through the steel work of mechanical workout.

Steel work can be any one form of wire rod, pole stock, bar or band.

Pole stock goods and bar goods can be the goods with all lengths diameter ratio from small to large.In other words, pole stock goods and bar goods can be from the various goods that to diameter or cross-sectional area are significantly less than length of diameter close to length.

Steel work can in the form by the steel work that any one is made in wire rod, pole stock, bar and band.Below various steel work is listed nonexclusively.The interested a kind of concrete steel work of applicant is the reinforcing mat for concrete construction and mineral industry, and it is made by being welded together with isolated parallel intersection wire rod by isolated parallel straight line material.The concrete steel work of the interested another kind of applicant is various reinforcing bars, is formed as binding or continuously helical material or other Common Shape (note, there is a lot of this kind of shape) as linear pattern reinforcing bar.The present invention and be not limited to the shape of steel work by the characteristic that the present invention realizes.

Steel work through mechanical workout can be cold rolling, cold-drawn or other any applicable goods through mechanical workout, as long as this mechanical workout causes the shape of cross section of goods to change, be not to change cross-sectional area, thus there is the energy input caused needed for alteration of form.Such as, alteration of form can be from circular cross section to oval cross section, and the area of this oval cross section and circular cross section is identical.

Steel work through mechanical workout can be cold rolling, cold-drawn or other any applicable goods through mechanical workout, and this goods there occurs reduction at the cross-sectional area after mechanical workout.

Cross-sectional area through the reduction of the steel work of mechanical workout can than the steel work cross-sectional area little at least 2% before mechanical workout.

Cross-sectional area through the reduction of the steel work of mechanical workout can than the steel work cross-sectional area little at least 5% before mechanical workout.

Cross-sectional area through the reduction of the steel work of mechanical workout can than the steel work cross-sectional area little at least 10% before mechanical workout.

Cross-sectional area through the reduction of the steel work of mechanical workout can than the steel work cross-sectional area little at least 15% before mechanical workout.

Cross-sectional area through the reduction of the steel work of mechanical workout can than the steel work cross-sectional area little at least 20% before mechanical workout.

Cross-sectional area through the reduction of the steel work of mechanical workout can than the steel work cross-sectional area little at least 40% before mechanical workout.

Cross-sectional area through the reduction of the steel work of mechanical workout can than the steel work cross-sectional area little at least 50% before mechanical workout.

Cross-sectional area through the reduction of the steel work of mechanical workout can than the steel work cross-sectional area little at least 60% before mechanical workout.

Cross-sectional area through the reduction of the steel work of mechanical workout can than the steel work cross-sectional area little at least 70% before mechanical workout.

The method of described production steel work can comprise and cooling through heat treated goods with any applicable rate of cooling from thermal treatment temp.Such as, can be quenched through heat treated goods by water cooling.In addition, such as, can cool through heat treated goods in ambient air.Applicant finds, substantially, rate of cooling not remarkably influenced is specially the characteristic of plasticity, yielding stress and tensile strength.But applicant finds, in some cases, on the above-mentioned characteristic of possibility remarkably influenced of quenching through heat treated goods, these situations are quenched after such as remaining on the thermal treatment temp specified time being at least 750 DEG C.In one example, remain on 750 DEG C after about 8 minutes, tensile strength increases suddenly, yielding stress and A _gtreduce.This is with the usual reaction of the steel of the heat-treated higher than austenitizing temperature.In this example, there is the heat treatment window reaching 8 minutes, in the follow-up quenching not influencing characteristic of this window.

As mentioned above, steel can be soft steel.

As mentioned above, steel can be medium carbon steel.

As mentioned above, steel can be Hi-Stren steel.

Hi-Stren steel can comprise the V that wt.% is greater than 0.040%.

Hi-Stren steel can comprise the V that wt.% is greater than 0.050%.

Hi-Stren steel can comprise the V that wt.% is greater than 0.060%.

Hi-Stren steel can comprise the N that wt.% is greater than 0.005%.

Hi-Stren steel can comprise the N that wt.% is greater than 0.015%.

Hi-Stren steel can comprise the N that wt.% is greater than 0.018%.

Hi-Stren steel can comprise other alloying elements, as Nb.

The invention provides a kind of method of producing steel work, it comprises:

A () carries out mechanical workout to charging steel;

B () is heat-treated the charging steel through mechanical workout, and keep or increase the plasticity of steel and the yielding stress of maintenance or increase steel; And

C () forms steel work.

The method of this production steel work can comprise repeatedly step (a), (b) and (c) of sequence.

The invention provides a kind of method of producing steel work, it comprises:

A () carries out mechanical workout to steel work; And

B () is heat-treated the steel work through mechanical workout, and keep or increase the plasticity of steel and the yielding stress of maintenance or increase steel.

The method of this production steel work can comprise repeatedly step (a) and (b) of sequence.

The invention provides a kind of method of producing steel work, it comprises:

A () carries out mechanical workout to charging steel;

B () forms steel work; And

C () is heat-treated steel work, and keep or increase the plasticity of this steel work and maintenance or increase the yielding stress of this steel work.

The invention provides a kind of method of producing steel work, it comprises:

A () carries out mechanical workout to charging steel;

B () forms steel work; And

C () is heat-treated formed steel work, and keep or increase plasticity, the maintenance of steel work or increase the yielding stress of steel work and keep or increase the tensile strength of steel work.

Relative to the unit elongation of the charging steel through mechanical workout, the unit elongation through heat treated steel can increase above 5%.

Unit elongation through heat treated steel can increase above 10%.

Unit elongation through heat treated steel can increase above 20%.

Unit elongation through heat treated steel can increase above 30%.

Unit elongation through heat treated steel can increase above 50%.

Unit elongation through heat treated steel can increase above 100%.

Unit elongation through heat treated steel can increase above 150%.

Unit elongation through heat treated steel can increase above 200%.

Yielding stress through heat treated steel can increase above 10%.

Yielding stress through heat treated steel can increase above 20%.

Yielding stress through heat treated steel can increase above 30%.

Yielding stress through heat treated steel can increase above 40%.

Produce the method for steel work can also comprise steel work is formed as another steel work.

Charging steel can be any one in soft steel, medium carbon steel and Hi-Stren steel.

Charging steel can be any applicable form.Charging steel can be any one form of wire rod, pole stock, bar or band.

It should be noted that mechanical processing steps can comprise the cross-sectional area reducing wire rod, pole stock and bar, namely reduce the diameter of wire rod, pole stock and bar.

It shall yet further be noted that mechanical processing steps can comprise the cross-sectional area reducing band, namely reduce the thickness of band.

It shall yet further be noted that mechanical processing steps can cause the shape of cross section of goods to change, and must not change cross-sectional area, thus the energy input that causes needed for alteration of form occurred.

Steel work can be the goods of any applicable form.

Steel work can in the form by the steel work that any one is made in wire rod, pole stock, bar and band.

Mechanical processing steps (a) can comprise cold rolling, cold-drawn or other any applicable mechanical processing steps, thisly comprises the cross-sectional area that mechanical processing steps reduces charging steel.

Heat treatment step can be performed with the temperature of the austenitizing temperature lower than steel.

Heat treatment step can be performed with the temperature lower than 800 DEG C.

Heat treatment step can be performed with the temperature lower than 750 DEG C.

Heat treatment step can be performed with the temperature lower than 700 DEG C.

Heat treatment step can be performed with the temperature lower than 600 DEG C.

Heat treatment step can be performed with the temperature lower than 550 DEG C.

Heat treatment step can be performed with the temperature lower than 500 DEG C.

Heat treatment step can be performed with the temperature lower than 450 DEG C.

Heat treatment step can be performed with the temperature lower than 400 DEG C.

Heat treatment step can be performed with the temperature lower than 300 DEG C.

Heat treatment step can be performed with the temperature lower than 250 DEG C.

Heat treatment step can be performed with the temperature lower than 200 DEG C.

Heat treatment step can be performed with the temperature lower than 150 DEG C.

Heat treatment step can be performed and be less than 16 hours.

Heat treatment step can be performed and be less than 10 hours.

Heat treatment step can be performed and be less than 6 hours.

Heat treatment step can be performed and be less than 5 hours.

Heat treatment step can be performed and be less than 4 hours.

Heat treatment step can be performed and be greater than 1 hour.

Heat treatment step can be performed and be greater than 45 minutes.

Heat treatment step can be performed and be greater than 30 minutes.

Heat treatment step can be performed and be greater than 10 minutes.

Heat treatment step can be performed and be greater than 5 minutes.

Heat treatment step can be performed and be greater than 1 minute.

Heat treatment step can be performed and be greater than 30 seconds.

Heat treatment step (b) can be performed under any applicable atmosphere.

Present invention also offers a kind of steel work made by method described above.

Steel work can have the yielding stress that is at least 500MPa and be at least the uniform elongation Agt of 1.5%.

Present invention also offers a kind of through mechanical workout and heat treated Hi-Stren steel goods, it has steel product ingredient as above, unit elongation and yielding stress.

This steel work can have tensile strength as above.

Present invention also offers a kind of through mechanical workout and heat treated low carbon steel products, it has steel product ingredient as above, unit elongation and yielding stress.

This steel work can have tensile strength as above.

Present invention also offers a kind of through mechanical workout and heat treated medium carbon steel goods, it has steel product ingredient as above, unit elongation and yielding stress.

This steel work can have tensile strength as above.

Steel work can in the form by the steel work that any one is made in wire rod as above, pole stock, bar and band.

For concreteness, steel work is net goods, it comprises parallel straight line material and parallel intersection wire rod, straight line material and the intersection online material intersection of wire rod weld together, and wire rod is steel wire rod, gauge or diameter of wire is at least 3mm, and wire rod is through mechanical workout and thermal treatment before welding together to form net, thus wire rod has the yielding stress that is at least 650MPa and is at least the uniform elongation Agt of 1.5%.

Lift an object lesson again, steel work is net goods, it comprises parallel straight line material and parallel intersection wire rod, straight line material and the intersection online material intersection of wire rod weld together, gauge or diameter of wire is at least 3mm, and wire rod is steel wire rod, wire rod before welding together to form net through mechanical workout, net is through Overheating Treatment, thus wire rod has the yielding stress that is at least 650MPa and is at least the uniform elongation Agt of 1.5%.

For concreteness, steel work is the binding formed by steel wire rod, the diameter of this wire rod is at least 3mm, and wire rod is through mechanical workout and thermal treatment before being formed as binding, thus wire rod has the yielding stress that is at least 650MPa and is at least the uniform elongation Agt of 1.5%.

For concreteness, steel work is the binding formed by steel wire rod, and the diameter of this wire rod is at least 3mm, wire rod before being formed as binding through mechanical workout, binding is through Overheating Treatment, thus wire rod has the yielding stress that is at least 650MPa and is at least the uniform elongation Agt of 1.5%.

With reference to Fig. 1-Figure 33 of accompanying drawing, the present invention is further described, and these accompanying drawings are the graphic representations of the following various combination carrying out the soft steel, medium carbon steel and the Hi-Stren steel sample that process according to the present invention: yielding stress (proof stress---MPa), tensile strength (MPa), unit elongation (with uniform elongation---A _gtmeasure) and heat treatment time.

The present invention is based on deep R&D work, it is mainly tested the soft steel of a great deal of, medium carbon steel and Hi-Stren steel sample.These samples comprise mechanical workout under different condition and with differing temps and the heat treated sample of different time.The important discovery of this R&D work is, for maintaining in the subsequent heat treatment of sample or obtaining the improvement of unit elongation and also obtain the improvement of yielding stress and tensile strength and maintain for yielding stress and tensile strength in the follow-up thermal treatment of sample, the mechanical workout of steel curved beam is vital.

Above-mentioned R&D work is carried out on steel wire rod, and this steel wire rod is applicable to manufacture reinforcing mat and for digging up mine and other reinforced articles of building trade.Steel wire rod is made up of soft steel, medium carbon steel and Hi-Stren steel.Steel wire rod by steel pole material larger for diameter or steel wire rod are rolled into diameter less and make.

Below to there being the R&D work carried out about soft steel, medium carbon steel and Hi-Stren steel to summarize.

● steel product ingredient---Hi-Stren steel, soft steel and medium carbon steel.The example of steel product ingredient lists as follows.

Hi-Stren steel

C	Mn	Si	P	S	Cu	Ni	Cr	Mo	V	Al	Nb	Ti	CE
														0.17	1.10	0.2	0.013	0.040	0.28	0.07	0.11	0.01	0.102	0.002	0.001	0.001	0.42
0.18	1.06	0.25	0.014	0.046	0.28	0.07	0.10	0.01	0.093	0.002	0.001	0.001	0.42

Soft steel

C	P	Mn	Si	S	Ni	Cr	Mo	Cu	Al-T	B
											0.06	0.006	0.50	0.15	0.009	0.006	0.12	0.001	0.014	0.002	0.0003
0.18	0.010	0.71	0.20	0.012	0.005		0.001	0.008	0.001	0.0003

Medium carbon steel

C	P	Mn	Si	S	Ni	Cr	Mo	Cu	Al-T	B
											0.31	0.018	0.70	0.24	0.012	0.002	0.010	0.001	0.004	0.001	0.0003

● original pole stock goods---in tolerance for wire rod, by common AS1442 or the similar operation of rolling, produce the pole stock sample of various different diameter---then, by wire rod less for these pole stock samples cold rolling one-tenth diameter to form test sample.It is the wire rod that the pole stock of 10mm is rolled into 9.5mm that sample comprises (a) diameter; B () diameter is the wire rod that the pole stock of 8mm is rolled into 7.7mm, 7.6mm, 7.5mm and 6.75mm; C the pole stock of () 10.5mm is rolled into 9.5mm; D the pole stock of () 8.5mm is rolled into 6.75mm; E () diameter is the wire rod that the pole stock of 12mm is rolled into 10.7mm; F () diameter is the wire rod that the pole stock of 8.5mm is rolled into 7.6mm; G () diameter is the wire rod that the pole stock of 5.5mm is rolled into 4.75mm, then align; H () diameter is the wire rod that the pole stock of 5.5mm is rolled into 4.75mm, then aligned by the straightening roll that diameter is less than the diameter of the straightening roll being used for (h) item sample; And (i) diameter is the wire rod that the pole stock of 5.5mm is rolled into 3.06mm.

● heat treatment furnace---fan forced air draft oven and resistance heading furnace.

● thermal treatment temp---see accompanying drawing.

● heat treatment time---see accompanying drawing.

● sample is cooled in atmosphere, and sample is quenched in water, wherein express the testing data carrying out in atmosphere cooling in Fig. 1-Figure 21 and Figure 26-Figure 33, in Figure 22-25, express the data of carrying out quenching in water.

● the size of sample---length is approximately 300mm.

● process of the test---on Instron machine, carry out tension test, and determine unit elongation by extensometer.Result in accompanying drawing comprises proof stress (PS) graphic representation, and wherein yielding stress is expressed as proof stress, and unit elongation is expressed as uniform elongation (A _{gt (-0.5%)}), and tensile strength (TS).

In Fig. 1-Figure 33 of Figure of description, partly summarize the result of research work, which will be described below and discuss.It should be noted that Fig. 1-Figure 25 lays particular emphasis on the work carried out on Hi-Stren steel (" HSLA ") sample, Figure 26-Figure 32 lays particular emphasis on low-Carbon steel specimen, and Figure 33 then lays particular emphasis on medium carbon steel sample.

Fig. 1 is the graphic representation changed with heat treatment time (0-30 minute) according to the unit elongation (Agt) of HSLA sample of the present invention, wherein these HSLA samples are heat-treated with 300 DEG C, 400 DEG C, 500 DEG C, 600 DEG C and 700 DEG C respectively, and sample comprises the wire sample that diameter is 9.5mm, to be that the pole stock of 10mm is cold rolling by diameter form for it.As can be seen from Fig. 1, in each thermal treatment temp, the plasticity of sample increases with heat treatment time, and the speed that plasticity increases increases with thermal treatment temp.

Fig. 2 is the graphic representation that the yielding stress (proof strength---MPa) according to HSLA sample of the present invention changes with heat treatment time (0-30 minute), wherein these HSLA samples are heat-treated with 300 DEG C, 400 DEG C, 500 DEG C, 600 DEG C and 700 DEG C respectively, and sample comprises the wire sample that diameter is 9.5mm, to be that the pole stock of 10mm is cold rolling by diameter form for it.As can be seen from Fig. 2, in each thermal treatment temp, corresponding to short heat treatment time, the yielding stress of cold-drawn sample increases.The yielding stress of the sample of heat-treating with comparatively high temps (such as, 500 DEG C, 600 DEG C and 700 DEG C) reduces along with the increase of heat treatment time.But for the sample of heat-treating with lesser temps (such as, 300 DEG C and 400 DEG C), yielding stress does not reduce with heat treatment time.In whole heat-treatment temperature range, realize yielding stress with relatively short heat treatment time and increase.This may be very important in process period and cost.

Fig. 3 is the graphic representation that the tensile strength (MPa) according to sample of the present invention changes with heat treatment time (0-30 minute), wherein these samples are heat-treated with 300 DEG C, 400 DEG C, 500 DEG C, 600 DEG C and 700 DEG C respectively, and sample comprises the HSLA wire sample that diameter is 9.5mm, it is that the pole stock of 10mm is formed by cold rolling mechanical workout of carrying out by diameter.This cold rolling cross-sectional area that makes reduces 9.75%.As can be seen from Fig. 3, in each thermal treatment temp, corresponding to short heat treatment time (being less than 4 minutes), the tensile strength of cold-drawn sample increases.The tensile strength of the sample of heat-treating with comparatively high temps (such as, 500 DEG C, 600 DEG C and 700 DEG C) reduces along with the increase of heat treatment time.But for the sample of heat-treating with lesser temps (such as, 300 DEG C and 400 DEG C), tensile strength does not reduce with heat treatment time.In addition, in whole heat-treatment temperature range, realize tensile strength with relatively short heat treatment time and increase.This may be very important in process period and cost.

The graphic representation that the unit elongation (measuring with uniform elongation Agt) that it is the HSLA wire sample of 9.5mm that Fig. 4 comprises according to diameter of the present invention changes with heat treatment time (0-5 hour), to be wherein that the pole stock of 10mm is cold rolling by diameter form and heat-treat with 300 DEG C these HSLA wire samples.This cold rolling cross-sectional area that makes reduces 9.75%.This graphic representation is described to " N10PLUS " curve in the accompanying drawings.Fig. 4 also comprises the correlation data that diameter is the Low Carbon Steel Wire Rod sample of 6.75mm, and to be that the pole stock of 8.5mm is cold rolling by diameter form and heat-treat in the same way this Low Carbon Steel Wire Rod sample.This cold rolling cross-sectional area that makes reduces 37%.This graphic representation is described to " 6.75EX8.5 " curve in the diagram.Fig. 4 shows plasticity and increases, and can think that this is caused by the thermal treatment undertaken by any one steel curved beam.

The graphic representation that the yielding stress (be expressed as proof stress---MPa) that Fig. 5 comprises the sample (HSLA and soft steel) of Fig. 4 changes with heat treatment time (0-5 hour), wherein these samples are heat-treated with 300 DEG C.

The graphic representation that the tensile strength (MPa) that Fig. 6 comprises the sample (HSLA and soft steel) of Fig. 4 changes with heat treatment time (0-5 hour), wherein these samples are heat-treated with 300 DEG C.

From Fig. 4-Fig. 6, the plasticity of N10PLUSHSLA sample, yielding stress and tensile strength all have increase, and usual reaction has then appearred in 6.75EX8.5 low-Carbon steel specimen, and its plasticity increases and yielding stress and tensile strength reduce.For N10PLUS sample, what is interesting is, such result obtains with 300 DEG C of such low heat-treatment temperature.

Fig. 4, Fig. 5 and Fig. 6 comprise dotted portion.The test work expressed in the drawings is the work of phase very early, applicant selects the heat treatment time of 1.15,2 and 4 hours to be because conventional wisdom shows, at least need within 1.2 hours, just to make soft steel produce normal reaction, that is, plasticity increases and yielding stress and tensile strength reduce---normal restorative thermal treatment reaction.When applicant to process N10PLUS sample and recognizes that there is intensity increases, applicant is just studied the shorter heat treatment time of this material.Impel applicant to pay close attention to the shorter heat treatment time of 6.75mm material and then paid close attention to every other material like this, applicant finds that the time of the increase of soft steel is shorter.Figure 26, Figure 27 and Figure 28 illustrate the increase of plasticity, yielding stress and tensile strength.This is the differing materials being cold-rolled to 6.75mm, thus has different initial strengths.Figure 29-Figure 32 has about with 500 DEG C of short period of time process soft steel, and in short heat treatment time situation shown in it, plasticity, yielding stress and tensile strength equally all increase.

Fig. 7 is the graphic representation changed with thermal treatment temp (0-500 DEG C) according to the unit elongation (Agt) of HSLA sample of the present invention, wherein these HSLA samples heat-treat 4 hours, and sample comprises the wire sample that diameter is 7.5mm, 7.6mm and 7.7mm, to be that the pole stock of 8mm is cold rolling by diameter form for it.These samples are cold rolling to carry out in various degree, and the highest reduction of cross-sectional area about 12%.As can be seen from Fig. 7, thermal treatment temp increases higher than the plasticity of the cold-drawn sample of 200 DEG C, and plasticity increases with thermal treatment temp and increases.

Fig. 8 is the graphic representation that the yielding stress (proof stress MPa) according to HSLA sample of the present invention changes with thermal treatment temp (0-500 DEG C), wherein these HSLA samples heat-treat 4 hours, and sample comprises the wire sample that diameter is 7.5mm, 7.6mm and 7.7mm, to be that the pole stock of 8mm is cold rolling by diameter form for it.These samples are cold rolling to carry out in various degree, and the highest reduction of cross-sectional area about 12%.As can be seen from Fig. 8, the yielding stress starting stage of each cold-drawn sample increases, and then increases along with thermal treatment temp and reduces.The yielding stress with the sample of higher cold rolling draft (coldreduction) is higher.In Fig. 8, the shape of graphic representation shows the window that there is thermal treatment temp, namely within the scope of 150-400 DEG C, there is window, and in this window, the yielding stress of sample enlarges markedly.In whole heat-treatment temperature range, the yielding stress of sample is higher than these samples yielding stress before the heat treatment.

Fig. 9 is the graphic representation changed with thermal treatment temp according to the tensile strength (MPa) of HSLA sample of the present invention, wherein these HSLA samples heat-treat 4 hours, and sample comprises the wire sample that diameter is 7.5mm, 7.6mm and 7.7mm, to be that the pole stock of 8mm is cold rolling by diameter form for it.These samples are cold rolling to carry out in various degree, and the highest reduction of cross-sectional area about 12%.As can be seen from Fig. 9, the tensile strength starting stage of each cold rolling sample increases, and then increases along with thermal treatment temp and reduces.The tensile strength with the sample of higher cold rolling draft (coldreduction) is higher.In Fig. 9, the shape of graphic representation shows the window that there is thermal treatment temp, namely within the scope of 150-350 DEG C, there is window, and in this window, the tensile strength of sample enlarges markedly.

Figure 10 is the graphic representation that the unit elongation (Agt) of HSLA sample changes with heat treatment time (0-7 hour), wherein these HSLA samples are heat-treated with 100 DEG C, and sample comprises the wire sample that diameter is 7.5mm, 7.6mm and 7.7mm, to be that the pole stock of 8mm is cold rolling by diameter form for it.These samples are cold rolling to carry out in various degree, and the highest reduction of cross-sectional area about 12%.As can be seen from Fig. 10, within the scope of whole heat treatment time, the plasticity of cold-drawn sample reduces generally slightly.This reduction is consistent with strain aging mechanism.Substantially, plasticity change is conventional, and instruction 100 DEG C of thermal treatment temps are too low.The plasticity with the sample of lower cold rolling draft is higher.

Figure 11 is the graphic representation that the yielding stress (proof strength---MPa) according to HSLA sample of the present invention changes with heat treatment time (0-7 hour), wherein these HSLA samples are heat-treated with 100 DEG C, and sample comprises the wire sample that diameter is 7.5mm, 7.6mm and 7.7mm, its pole stock cold-drawn being 8mm by diameter forms.These samples are to carry out cold-drawn in various degree, and the highest reduction of cross-sectional area about 12%.As can be seen from Fig. 11, within the scope of whole heat treatment time, the yielding stress of cold-drawn sample increases (although and not obvious).The yielding stress with the sample of higher cold rolling draft is higher.

Figure 12 is the graphic representation changed with heat treatment time (0-7 hour) according to the tensile strength (MPa) of HSLA sample of the present invention, wherein these HSLA samples are heat-treated with 100 DEG C, and sample comprises the wire sample that diameter is 7.5mm, 7.6mm and 7.7mm, to be that the pole stock of 8mm is cold rolling by diameter form for it.These samples are cold rolling to carry out in various degree, and the highest reduction of cross-sectional area about 12%.As can be seen from Fig. 12, within the scope of whole heat treatment time, the tensile strength of cold-drawn sample changes slightly.The tensile strength with the sample of higher cold rolling draft is higher.

Figure 13 is the graphic representation changed with heat treatment time (0-16 hour) according to the unit elongation (Agt) of HSLA sample of the present invention, wherein these HSLA samples are heat-treated with 300 DEG C, and sample comprises the wire sample that diameter is 7.5mm, 7.6mm and 7.7mm, to be that the pole stock of 8mm is cold rolling by diameter form for it.These samples are cold rolling to carry out in various degree, and the highest reduction of cross-sectional area about 12%.As can be seen from Fig. 13, for each sample, when plasticity is after initial reduction (this is consistent with normal timeliness) suddenly, at 300 DEG C and in relatively short heat treatment time (being thirty minutes long), plasticity enlarged markedly in the starting stage, and heat-treating with this temperature about after 3 hours, plasticity tends towards stability.The unit elongation with the sample of lower cold rolling draft is higher.

Figure 14 is the graphic representation that the yielding stress (proof strength---MPa) according to HSLA sample of the present invention changes with heat treatment time (0-16 hour), wherein these HSLA samples are heat-treated with 300 DEG C, and sample comprises the wire sample that diameter is 7.5mm, 7.6mm and 7.7mm, to be that the pole stock of 8mm is cold rolling by diameter form for it.These samples are cold rolling to carry out in various degree, and the highest reduction of cross-sectional area about 12%.As can be seen from Fig. 14, for each sample, at 300 DEG C and in relatively short heat treatment time (0-45 minute), yielding stress enlarged markedly in the starting stage, and after heat-treating about 45 minutes with this temperature, yielding stress tends towards stability.The yielding stress with the sample of higher cold rolling draft is higher.In whole heat-treatment temperature range, the yielding stress of sample is higher than these samples yielding stress before the heat treatment.

Figure 15 is the graphic representation changed with heat treatment time (0-16 hour) according to the tensile strength (MPa) of HSLA sample of the present invention, wherein these HSLA samples are heat-treated with 300 DEG C, and sample comprises the wire sample that diameter is 7.5mm, 7.6mm and 7.7mm, to be that the pole stock of 8mm is cold rolling by diameter form for it.These samples are cold rolling to carry out in various degree, and the highest reduction of cross-sectional area about 12%.As can be seen from Fig. 15, for each sample, at 300 DEG C and in relatively short heat treatment time (0-45 minute), tensile strength enlarged markedly in the starting stage, and after heat-treating about 45 minutes with this temperature, tensile strength tends towards stability.The tensile strength with the sample of higher cold rolling draft is higher.In whole heat-treatment temperature range, the tensile strength of sample is higher than these samples tensile strength before the heat treatment.

Figure 16 is the graphic representation changed with heat treatment time (0-30 minute) according to the unit elongation (Agt) of HSLA sample of the present invention, wherein these HSLA samples are heat-treated with 300 DEG C, and sample comprises the wire sample that diameter is 7.5mm, 7.6mm and 7.7mm, to be that the pole stock of 8mm is cold rolling by diameter form for it.These samples carry out cold rolling and thermal treatment with the condition identical with the sample of Figure 13.Sample is cold rolling to carry out in various degree, and the highest reduction of cross-sectional area about 12%.This graphic representation mainly illustrates the initial 30 minutes heat treatment times emphasized in the discussion of Figure 13.As can be seen from Fig. 16, for each sample, at 300 DEG C, after plasticity reduces (this is consistent with normal timeliness) at first, plasticity increases steadily with heat treatment time, and the plasticity with the sample of lower cold rolling draft is higher.

Figure 17 is the graphic representation that the yielding stress (proof strength---MPa) according to HSLA sample of the present invention changes with heat treatment time (0-30 minute), wherein these HSLA samples are heat-treated with 300 DEG C, and sample comprises the wire sample that diameter is 7.5mm, 7.6mm and 7.7mm, to be that the pole stock of 8mm is cold rolling by diameter form for it.Sample is cold rolling to carry out in various degree, and the highest reduction of cross-sectional area about 12%.These samples carry out cold rolling and thermal treatment with the condition identical with the sample of Figure 14.This graphic representation mainly illustrates the initial 30 minutes heat treatment times emphasized in the discussion of Figure 14.As can be seen from Fig. 17, for each sample, at 300 DEG C, yielding stress increases steadily with heat treatment time substantially.The yielding stress with the sample of higher cold rolling draft is higher.The increase of yielding stress is far above expecting to produce from normal strain aging.Normal strain aging is disadvantageous, because it causes plasticity to decline.

Figure 18 is the graphic representation changed with heat treatment time (0-30 minute) according to the tensile strength (MPa) of HSLA sample of the present invention, wherein these HSLA samples are heat-treated with 300 DEG C, and sample comprises the wire sample that diameter is 7.5mm, 7.6mm and 7.7mm, to be that the pole stock of 8mm is cold rolling by diameter form for it.Sample is cold rolling to carry out in various degree, and the highest reduction of cross-sectional area about 12%.These samples carry out cold rolling and thermal treatment with the condition identical with the sample of Figure 15.This graphic representation mainly illustrates the initial 30 minutes heat treatment times emphasized in the discussion of Figure 15.As can be seen from Fig. 18, for each sample, at 300 DEG C, tensile strength increases steadily with heat treatment time.The tensile strength with the sample of higher cold rolling draft is higher.

Figure 19 is the graphic representation changed with heat treatment time (0-30 minute) according to the unit elongation (Agt) of HSLA sample of the present invention, wherein these HSLA samples are heat-treated with 500 DEG C, and sample comprises the wire sample that diameter is 7.5mm, 7.6mm and 7.7mm, to be that the pole stock of 8mm is cold rolling by diameter form for it.Sample is cold rolling to carry out in various degree, and the highest reduction of cross-sectional area about 12%.As can be seen from Fig. 19, for each sample, at 500 DEG C, when plasticity is after the starting stage reduces (this is consistent with normal timeliness), plasticity increases steadily with heat treatment time, and the plasticity with the sample of lower cold rolling draft is higher.

Figure 20 is the graphic representation that the yielding stress (proof strength---MPa) according to HSLA sample of the present invention changes with heat treatment time (0-30 minute), wherein these HSLA samples are heat-treated with 500 DEG C, and sample comprises the wire sample that diameter is 7.5mm, 7.6mm and 7.7mm, to be that the pole stock of 8mm is cold rolling by diameter form for it.Sample is cold rolling to carry out in various degree, and the highest reduction of cross-sectional area about 12%.As can be seen from Fig. 20, for each sample, the thermal treatment temp of 500 DEG C, yielding stress increased in the starting stage, and the yielding stress of each sample reaches maximum yielding stress after 10 min.The yielding stress of each sample reduces with heat treatment time after more than 10 minutes.The yielding stress with the sample of higher cold rolling draft is higher.In whole heat-treatment temperature range, the yielding stress of sample is higher than these samples yielding stress before the heat treatment.

Figure 21 is the graphic representation changed with heat treatment time (0-30 minute) according to the tensile strength (MPa) of HSLA sample of the present invention, wherein these HSLA samples are heat-treated with 500 DEG C, and sample comprises the wire sample that diameter is 7.5mm, 7.6mm and 7.7mm, to be that the pole stock of 8mm is cold rolling by diameter form for it.Sample is cold rolling to carry out in various degree, and the highest reduction of cross-sectional area about 12%.As can be seen from Fig. 21, for each sample, the thermal treatment temp of 500 DEG C, tensile strength increased in the starting stage, and the tensile strength of each sample reaches the maximum tensile strength after 10 min, and the tensile strength of each sample reduces with heat treatment time after more than 10 minutes.The tensile strength with the sample of higher cold rolling draft is higher.

Figure 22 is the graphic representation that the unit elongation (Agt) being the HSLA wire sample of 6.75mm according to diameter of the present invention changes with heat treatment time (0-20 minute), wherein to be that the pole stock of 8mm is cold rolling by diameter form these HSLA wire samples, and heat-treat with 750 DEG C the time exceeding and reach 20 minutes, then quench in water.This cold rolling cross-sectional area that makes reduces 29%.As can be seen from Fig. 22, at 750 DEG C, after plasticity reduces (this is consistent with normal strain aging) at first, plasticity increases steadily with heat treatment time, until 7 minutes places, plasticity reduces suddenly afterwards, suddenly increase again, then stable at about 10-12 minute place.As can be seen from Fig. 22, in the heat treatment time between 2 minutes and 7 minutes, sample being carried out in water quenching heat treatment can not have a negative impact to plasticity.By forming being that the pole stock of 8mm is cold rolling by diameter in the result in Figure 22 and Figure 19 and contrasting with the result of 500 DEG C of 7.5mm, 7.6mm and 7.7mm materials of heat-treating, the height of 7.5mm, 7.6mm and 7.7mm material of plasticity ratio Figure 19 of the 6.75mm material of Figure 22 can be seen.This discovery is contrary with the situation of 7.5mm, 7.6mm and 7.7mm material shown in Figure 19, and according to Figure 19, plasticity increases with cold rolling draft and reduces.This is likely because of the larger plasticity of the higher generation of thermal treatment temp of 6.75mm material.

Figure 23 is the graphic representation that the yielding stress (proof strength---MPa) of the HSLA wire sample of 6.75mm and tensile strength (MPa) change with heat treatment time (0-20 minute) according to diameter of the present invention, wherein to be that the pole stock of 8mm is cold rolling by diameter form these HSLA wire samples, and heat-treat with 750 DEG C, then quench in water.As can be seen from Fig. 23, thermal treatment reaches the yielding stress of carrying out the sample quenched in water of then carrying out for 7 minutes quenching and tensile strength is improved.Then the thermal treatment carrying out being less than 8 minutes carried out quenching and caused tensile strength to enlarge markedly and yielding stress significantly reduces.As can be seen from Fig. 23, there is the window being in thermal treatment temp and reaching the heat treatment time of 7 minutes, in this window, yielding stress and tensile strength improve.Quenching does not destroy mechanical characteristics.The advantage of quenching is that goods are available in time.

Figure 24 is the graphic representation that the unit elongation (Agt) being the HSLA wire sample of 6.75mm according to diameter of the present invention changes with heat treatment time (0-20 minute), wherein to be that the pole stock of 8mm is cold rolling by diameter form these HSLA wire samples, and heat-treat with 500 DEG C, then quench in water.As can be seen from Fig. 24, at 500 DEG C, after plasticity reduces (this is consistent with normal strain aging) at first, plasticity increases steadily with heat treatment time.As can be seen from Fig. 24, after heat treatment time was more than 5 minutes, sample being carried out in water quenching heat treatment can not have a negative impact to plasticity.In addition, it can also be seen that, the higher thermal treatment temp of 750 DEG C of the sample mentioned in above paragraph produces ratio with the plasticity of 500 DEG C of samples of heat-treating high 2%.

Figure 25 is the graphic representation that the yielding stress (proof strength---MPa) of the HSLA wire sample of 6.75mm and tensile strength (MPa) change with heat treatment time (0-20 minute) according to diameter of the present invention, wherein to be that the pole stock of 8mm is cold rolling by diameter form these HSLA wire samples, and heat-treat with 500 DEG C, then quench in water.As can be seen from Fig. 25, sample is carried out in water quenching heat treatment substantially to have a negative impact to yielding stress and tensile strength.In other words, in this thermal treatment temp, steel is carried out in water quench treatment and there is not negative effect.But it should be noted that these heat-treat conditions cause yielding stress and tensile strength to increase.

Figure 26-Figure 31 lays particular emphasis on the result to the R&D work that low-Carbon steel specimen carries out.

Figure 26 is the graphic representation that the unit elongation (Agt) according to sample of the present invention changes with heat treatment time (0-30 minute), wherein these samples are heat-treated with 500 DEG C, and sample comprises the Low Carbon Steel Wire Rod sample that diameter is 9.5mm and 6.75mm, to be that the pole stock of 10mm and 8.5mm is cold rolling by diameter respectively form for it.This cold rolling cross-sectional area that makes reduces 18% and 37% respectively.As can be seen from Fig. 26, at 500 DEG C, after plasticity reduces (this is consistent with normal strain aging) at first, plasticity increases steadily with heat treatment time.

Figure 27 is the graphic representation that the yielding stress (proof strength---MPa) according to sample of the present invention changes with heat treatment time (0-30 minute), wherein these samples are heat-treated with 500 DEG C, and sample comprises the Low Carbon Steel Wire Rod sample that diameter is 9.5mm and 6.75mm, to be that the pole stock of 10.5mm and 8.5mm is cold rolling by diameter respectively form for it.This cold rolling cross-sectional area that makes reduces 18% and 37% respectively.As can be seen from Fig. 27, through more degree of depth mechanical workout sample (namely, 6.75mm sample) the yielding stress initial period increase (until 2 minutes heat treatment times), then reduce with heat treatment time, after the heat treatment time of 7 minutes, yielding stress is decreased to originally intensity, i.e. cold working intensity.The result that yielding stress increased in the initial period is astonishing, and this shows to there is heat treatment window, can realize yielding stress and increase in this window.As can be seen from Fig. 27, the yielding stress of the sample (that is, 9.5mm sample) of non-degree of depth mechanical workout is not subject to negative impact reaching in the thermal treatment of 8 minutes.If considered in conjunction with Figure 26, so expressed in Figure 27 result is significant result, this is because this result shows to heat-treat the steel of this deep processing and realizes the plasticity increase of Figure 26, and do not make yielding stress reduce, and the more important thing is yielding stress can be made to increase.

Figure 28 is the graphic representation that the tensile strength (MPa) according to sample of the present invention changes with heat treatment time (0-30 minute), wherein these samples are heat-treated with 500 DEG C, and sample comprises the Low Carbon Steel Wire Rod sample that diameter is 9.5mm and 6.75mm, to be that the pole stock of 10.5mm and 8.5mm is cold rolling by diameter respectively form for it.This cold rolling cross-sectional area that makes reduces 18% and 37% respectively.As can be seen from Fig. 28, the tensile strength through the sample (that is, 9.5mm sample) of non-degree of depth mechanical workout increases (until 8 minutes heat treatment times) in the initial period, then reduces with heat treatment time.The result that tensile strength increased in the initial period is astonishing, and this shows to there is heat treatment window, can realize tensile strength and increase in this window.If considered in conjunction with Figure 26 and Figure 27, so the result of Figure 28 is significant result, this is because this result shows to heat-treat the steel of this deep processing and realizes the plasticity increase of Figure 26, the yielding stress increase of Figure 27, and tensile strength is not made to reduce.

Figure 29 is the graphic representation that yielding stress (proof strength---MPa), tensile strength (MPa) and unit elongation (Agt) according to sample of the present invention change with heat treatment time (0-15 minute), wherein these samples are heat-treated with 500 DEG C, and sample comprises the Low Carbon Steel Wire Rod sample that diameter is 10.7mm, to be that the pole stock of 12mm is cold rolling by diameter form for it.This cold rolling cross-sectional area of sample that makes reduces 20%.The figure line of often kind of parameter is depicted as the lines of fitting the most with actual data point.As can be seen from Fig. 29, yielding stress, tensile strength and plasticity increase steadily with heat treatment time.The result that yielding stress increases is astonishing.In whole heat-treatment temperature range, the yielding stress of sample is higher than these samples yielding stress before the heat treatment.

Figure 30 is the graphic representation that yielding stress (proof strength---MPa), tensile strength (MPa) and unit elongation (Agt) according to sample of the present invention change with heat treatment time (0-15 minute), wherein these samples are heat-treated with 500 DEG C, and sample comprises the Low Carbon Steel Wire Rod sample that diameter is 8.5mm, to be that the pole stock of 7.6mm is cold rolling by diameter form for it.This cold rolling cross-sectional area of sample that makes reduces 20%.The figure line of often kind of parameter is depicted as the lines of fitting the most with actual data point.As can be seen from Fig. 30, yielding stress and tensile strength increase with heat treatment time at first and reached peak value at about 5 minutes, then extend with heat treatment time and reduce gradually.The result that yielding stress increased in the starting stage is astonishing, and this shows to there is heat treatment window, can realize yielding stress and increase in this window.In whole heat-treatment temperature range, the yielding stress of sample is higher than these samples yielding stress before the heat treatment.Be also shown in from Figure 30, plasticity increases steadily with heat treatment time.

Figure 31 is the graphic representation that yielding stress (proof strength---MPa), tensile strength (MPa) and unit elongation (Agt) according to sample of the present invention change with heat treatment time (0-15 minute), wherein these samples are heat-treated with 500 DEG C, and sample comprises the Low Carbon Steel Wire Rod sample that diameter is 4.75mm, to be that the pole stock of 5.5mm is cold rolling by diameter form for it.Wire sample is before the heat treatment through straightener.This cold rolling cross-sectional area of sample that makes reduces 25%.The figure line of often kind of parameter is depicted as the lines of fitting the most with actual data point.As can be seen from Fig. 31, yielding stress and tensile strength increase quite rapidly with heat treatment time at first and reach peak value at about 2-3 minute, then extend with heat treatment time and reduce gradually.The result that yielding stress increased in the starting stage is astonishing, and this shows to there is heat treatment window, can realize yielding stress and increase in this window.In whole heat-treatment temperature range, the yielding stress of sample is higher than these samples yielding stress before the heat treatment.Be also shown in from Figure 31, plasticity increases steadily with heat treatment time.

Figure 32 is the graphic representation that yielding stress (proof strength---MPa), tensile strength (MPa) and unit elongation (Agt) according to sample of the present invention change with heat treatment time (0-15 minute), wherein these samples are heat-treated with 500 DEG C, and sample comprises the Low Carbon Steel Wire Rod sample that diameter is 4.75mm, to be that the pole stock of 5.5mm is cold rolling by diameter form for it.Wire sample is before the heat treatment through straightener.This cold rolling cross-sectional area of sample that makes reduces 25%.The testing sequence of this test with in Figure 31 expressed test between unique difference relevant with the straightener that uses.This straightening roll is that diameter compares for the little straightening roll of the diameter of the straightening roll of (h) item sample.The figure line of often kind of parameter is depicted as the lines of fitting the most with actual data point.As can be seen from Fig. 32, yielding stress and tensile strength increase quite rapidly with heat treatment time at first and reach peak value at about 2-3 minute, then extend with heat treatment time and reduce gradually.The result that yielding stress increased in the starting stage is astonishing, and this shows to there is heat treatment window, can realize yielding stress and increase in this window.In whole heat-treatment temperature range, the yielding stress of sample is higher than these samples yielding stress before the heat treatment.Be also shown in from Figure 32, plasticity increases steadily with heat treatment time.Closely similar in test-results in Figure 31 and Figure 32, except being different from the straightener of Figure 32 because of the straightener of Figure 31, yielding stress, tensile strength and unit elongation are slightly high.

Figure 33 is the graphic representation that yielding stress (proof strength---MPa), tensile strength (MPa) and unit elongation (Agt) according to sample of the present invention change with heat treatment time (0-15 minute), wherein these samples are heat-treated with 500 DEG C, and sample comprises the medium carbon steel wire sample that diameter is 3.06mm, to be that the pole stock of 5.5mm is cold rolling by diameter form for it.This cold rolling cross-sectional area of these samples that makes reduces 69% respectively.The figure line of often kind of parameter is depicted as the lines of fitting the most with actual data point.As can be seen from Fig. 33, yielding stress increases quite rapidly with heat treatment time at first and reached peak value at about 3 minutes, then extends with heat treatment time and reduces gradually.The result that yielding stress increased in the starting stage is astonishing, and this shows to there is heat treatment window, can realize yielding stress and increase in this window.In whole heat-treatment temperature range, the yielding stress of sample is higher than these samples yielding stress before the heat treatment.Be also shown in from Figure 33, plasticity increases steadily with heat treatment time.

The cut-and-try work that applicant carries out shows, for the wire rod with ribbing carrying out processing according to the present invention and smooth wire rod, mechanism of the present invention is without any difference.

Generally speaking, as in accompanying drawing shown by the result summed up, applicant finds, importantly, by mechanical workout and heat treated combination, the plasticity of the wire rod be made up of Hi-Stren steel, medium carbon steel and soft steel (measuring with unit elongation), yielding stress and tensile strength can increase.Due to following reason, this discovery is important discovery:

● can reduce significantly to manufacture the steel consumption needed for goods, and not make the supporting capacity of steel in goods decline.Reduce the economy that required steel consumption improves construction, and reduce carbon footprint.

● the goods with higher-strength and plasticity can be obtained.

● can design be changed, and thus the cost of the composite product be made up of steel work can be changed.An example is for the reinforced concrete product in building trade.By the present invention, the steel consumption in these goods and/or concrete amount can be reduced, or improve the structure properties of these goods under given steel consumption.

● owing to can perform method of the present invention with lower cost of capital and operation cost, therefore the method is economical.

The present invention may be used for the different steps that end-use articles manufactures, because herein is provided sizable handiness.Such as, can process to steel wire rod the yielding stress and the plasticity that increase wire rod according to the present invention, and then reel.

Goods through winding can be formed as end-use articles, as helical, binding etc.Or, can production standard helical, reeled, then carry out processing to produce the goods as mesh sheet and binding etc., and can be processed to these goods the yielding stress and the plasticity that increase goods according to the present invention.

When not departing from the spirit of the invention described above, various amendment can be carried out to the present invention.

Exemplarily, the report of above-mentioned R&D work lays particular emphasis on wire rod.But applicant thinks, the result found by wire rod should be able to be transplanted to pole stock, bar and band steel work.

Claims

1. produce the method for steel work, comprising:

Steel work through mechanical workout is heat-treated; And

Keep or increase the plasticity of steel and the yielding stress of maintenance or increase steel.

2. produce the method for steel work, comprising:

Steel work through mechanical workout is heat-treated; And

Keep or increase the plasticity of steel, maintenance or increase the yielding stress of steel and keep or increase the tensile strength of steel.

3. method as claimed in claim 1 or 2, wherein, the Plastic phase measured with unit elongation through heat treated steel increases above 5% for the plasticity measured with unit elongation of the steel through mechanical workout.

4. the claim as described in aforementioned any one of claim, wherein, the yielding stress through heat treated steel increases above 5% relative to the yielding stress of the steel through mechanical workout.

5. produce the method for steel work, comprise

A () carries out mechanical workout to charging steel;

C () forms steel work.

6. method as claimed in claim 5, wherein, mechanical processing steps (a) comprises cold rolling, cold-drawn or other any applicable mechanical processing steps, and the mechanical processing steps comprised as long as this reduces the cross-sectional area of charging steel.

7. method as claimed in claim 5, wherein, mechanical processing steps (a) comprises cold rolling, cold-drawn or other any applicable mechanical processing steps, as long as the mechanical processing steps that comprises this changes the shape of cross section of charging steel and must not change cross-sectional area, thus the energy input that causes needed for alteration of form occurred.

8. produce the method for steel work, comprising:

A () carries out mechanical workout to steel work; And

B () is heat-treated the steel work through mechanical workout, and increase the plasticity of steel and the yielding stress of maintenance or increase steel.

9. method as claimed in claim 8, wherein, mechanical processing steps (a) comprises cold rolling, cold-drawn or other any applicable mechanical processing steps, and the mechanical processing steps comprised as long as this reduces the cross-sectional area of steel work.

10. method as claimed in claim 8, wherein, mechanical processing steps (a) comprises cold rolling, cold-drawn or other any applicable mechanical processing steps, as long as the mechanical processing steps that comprises this changes the shape of cross section of charging steel and must not change cross-sectional area, thus the energy input that causes needed for alteration of form occurred.

The method of 11. production steel work, comprises

A () carries out mechanical workout to charging steel;

B () forms steel work; And

C () is heat-treated steel work, and increase the plasticity of steel work and the yielding stress of maintenance or increase steel work.

The method of 12. production steel work, comprises

A () carries out mechanical workout to charging steel;

B () forms steel work; And

C () is heat-treated formed steel work, and increase the plasticity of steel work and maintenance or increase yielding stress and the tensile strength of steel work.

13. methods as described in claim 11 or 12, wherein, mechanical processing steps (a) is cold rolling, cold-drawn or other any applicable mechanical processing steps, and the mechanical processing steps comprised as long as this reduces the cross-sectional area of charging steel.

14. methods as described in claim 11 or 12, wherein mechanical processing steps (a) comprises cold rolling, cold-drawn or other any applicable mechanical processing steps, as long as the mechanical processing steps that comprises this changes the shape of cross section of charging steel and must not change cross-sectional area, thus the energy input that causes needed for alteration of form occurred.

15. claims as described in aforementioned any one of claim, wherein, steel is Hi-Stren steel.

16. claims as described in aforementioned any one of claim, wherein, steel is soft steel.

17. claims as described in aforementioned any one of claim, wherein, steel is medium carbon steel.

The method of 18. production steel work, comprising:

For steel work is selected as raw-material charging steel;

Select the mechanical workout of charging steel or the goods be made up of charging steel, heat treatment time and temperature condition of heat treatment, thus provide required mechanical characteristics for steel work;

Perform mechanical workout and heat treatment step, and keep or increase the plasticity of steel and the yielding stress of maintenance or increase steel; And

Produce the steel work with required mechanical characteristics.

19. through mechanical workout and heat treated steel work, and it is made by the method described in aforementioned any one of claim.

20. steel work as claimed in claim 19, comprise wire rod, pole stock, bar or band any one.

21. steel work as claimed in claim 20, comprise by the steel work that in wire rod, pole stock, bar and band, any one is made.