CN101775545B

CN101775545B - Low-alloy high-strength high-toughness wear-resistant steel plate and manufacturing method thereof

Info

Publication number: CN101775545B
Application number: CN2009100452741A
Authority: CN
Inventors: 李红斌; 姚连登; 赵小婷; 赵四新
Original assignee: 宝山钢铁股份有限公司
Priority date: 2009-01-14
Filing date: 2009-01-14
Publication date: 2011-10-12
Also published as: CN101775545A

Abstract

The invention provides a low-alloy high-strength high-toughness wear-resistant steel plate which is characterized in that the low-alloy high-strength high-toughness wear-resistant steel plate comprises the following chemical compositions in percentage by weight: 0.15-0.27 wt% of C, 0.20-1.0 wt% of Si, 0.80-1.8 wt% of Mn, less than 0.030 wt% of P, less than 0.010 wt% of S, 0.20-1.0 wt% of Cr, 0.10-0.40 wt% of Mo, 0.010-0.040 wt% of Nb, 0.0005-0.0040 wt% of B, 0.020-0.060 wt% of Al, 0.004-0.030 wt% of Ti and balance of Fe and inevitable impurities; and in addition, the contents of Cr, Mo and Nb satisfy the condition: Cr+Mo+Nb is more than or equal to 0.35 wt%, and the contents of Cr and Mo satisfy the condition: Cr/Mo is more than or equal to 1.2. The low-alloy high-strength high-toughness wear-resistant steel plate of the invention has the charateristics that the hardness is more than 450 HB, the tensile strength is more than 1500 MPa, the yield strength is more than 1200 MPa, the elongation ratio is more than 15%, the impact energy is more than 80 J, the plate thickness can reach 80 mm, and fine texture can be martensite or martensite and retained austenite. The steel has low production cost, simple and easily mastered production process, high strength and hardness and favorable toughness and weldability.

Description

A kind of low-alloy high-strength high-toughness wear-resistant steel plate and manufacture method thereof

Technical field

The present invention relates to wear resisting steel, specifically, the present invention relates to a kind of low-alloy high-strength high-toughness wear-resistant steel plate and manufacture method thereof.

Background technology

In today of science and technology and modern industry high speed development, the running speed of mechanical means is more and more higher, and many workpiece and equipment lost efficacy rapidly owing to wear and tear, and waste of material that causes and financial loss are quite surprising.According to incompletely statistics, China is only in metallurgy, mine, electric power, coal and agricultural machinery department, annual about 40,000,000,000 yuan of the financial loss that causes owing to the wear of work.Therefore, the development of high-abrasive material has become the important factor that influences modern production efficient.

Generally select for use Hadfield Steel to produce wear parts traditionally.The strain inducing martensitic transformation can take place in Hadfield Steel under big impact loading, improve its wear resistance.The Hadfield Steel Brinell hardness has only 180～220, and work-ing life is short, does not meet and sets up conservation-minded society's developing direction, and carbon or high-carbon alloy steel in adopting usually at present improve its mechanical property by modifier treatment, to satisfy the requirement of actual condition to wearing piece.

The wear resistance of material depends primarily on its hardness.Higher hardness can provide good wear resistance.Adjust the alloy element component in the steel alloy, increase carbon content and add an amount of trace element such as elements such as chromium, molybdenum, nickel, vanadium, tungsten, cobalt, boron and titanium, make full use of precipitation strength, the different schedule of reinforcements with phase transformation strengthening, dislocations strengthening etc. of refined crystalline strengthening improve the hardness of steel.

Toughness also has very important influence to the wear resistance of material.By adjusting composition and thermal treatment process, can obtain good comprehensive mechanical performance, and then improve wear resisting property in inner control low-alloy wear-resistant steel hardness and flexible rational Match in a big way, make it satisfy the needs of different wear working conditions.

By adjusting the composition of optimizing steel and the steel alloy that technology can obtain good abrasion resistance.Carbon content is very big to the performance impact of steel.Along with the increase of carbon content, the lattice parameter of the martensite HCP lattice of the formation of quenching increases, and the hardness of organizing after the quenching increases.But the carbon content increase can cause the toughness of steel to descend, and too high carbon severe exacerbation the welding property of steel, limited the use range of hard high-carbon alloy steel; Chromium can significantly improve the antioxygenation of steel, improves hardening capacity, increases resistance to corrosion, improves wear resistance; Nickel can crystal grain thinning, improves the toughness and the plasticity of low alloy steel simultaneously by refined crystalline strengthening; Molybdenum is a ferrite former, can promote martensite to form, and increases the hardening capacity of steel and improves the stability of carbide; Rare earth element can improve as-cast structure, crystal grain thinning and the cleaning molten steel of steel alloy.The more alloying element that adds in the steel can increase the manufacturing cost of steel, has reduced its practical application performance as Industrial products.

Welding can solve the connection of various steel, is crucial complete processing, has a very important role in engineering is used.Welding cold cracking is the weldprocedure defective of the most normal appearance, and especially when weld high strength steel, the tendency that cold crack occurs is very big.For preventing that cold crack from producing, normally weld preheating, postweld heat treatment have caused the complicacy of weldprocedure, and not operability in particular cases jeopardizes welded safe reliability.For high-intensity wear-resisting steel plate, Welding Problems is particularly evident.The chemical ingredients of material is to the welding property important influence.Carbon and alloying element to the available carbon equivalent of the influence of the welding of steel (carbon equivalent of steel be exactly comprise in the steel carbon to the suitable content that hardens, influential alloying element content such as cold crack and embrittlement is converted into carbon.) represent that by the estimation to the carbon equivalent of steel, can tentatively weigh the height of Hi-Stren steel cold cracking sensitivity, this determines to have important directive function to welding condition such as preheating, postweld heat treatment, heat input etc.The formula of the carbon equivalent that international welding association is confirmed is

Ceq＝C+Mn/6+(Cr+Mo+V)/5+(Ni+Cu)/15

Increase steel interalloy constituent content and can obtain good mechanical property, but influence its weldability and increased the production cost of steel, so it does not have favorable economic benefit and social benefit.Therefore, control alloying element content, research and development low cost and the simple low-alloy wear-resistant steel of technology are the inexorable trends of social economy and Iron And Steel Industry development.

Summary of the invention

At the above-mentioned deficiency of prior art, one object of the present invention is to provide a kind of low-alloy high-strength high-toughness wear-resistant steel plate.

The chemical ingredients of low-alloy high-strength high-toughness wear-resistant steel plate of the present invention and content are C:0.15～0.27wt.%, Si:0.20～1.0wt.%, Mn:0.80～1.8wt.%, P:＜0.030wt.%, S:＜0.010wt.%, Cr:0.20～1.0wt.%, Mo:0.10～0.40wt.%, Nb:0.010～0.040wt.%, B:0.0005～0.0040wt.%, Al:0.020～0.060wt.%, Ti:0.004～0.030wt.%, and surplus is Fe and unavoidable impurities; And the content of Cr, Mo, Nb satisfies Cr+Mo+Nb 〉=0.35wt.%; The content of Cr, Mo satisfies Cr/Mo 〉=1.2.

Preferably, the chemical ingredients of described low-alloy high-strength high-toughness wear-resistant steel plate and content are: C:0.17～0.27wt.%, Si:0.30～1.0wt.%, Mn:0.80～1.8wt.%, P:＜0.030wt.%, S:＜0.010wt.%, Cr:0.40～1.0wt.%, Mo:0.15～0.40wt.%, Nb:0.010～0.040wt.%, B:0.0005～0.0040wt.%, Al:0.020～0.060wt.%, Ti:0.004～0.030wt.%, and surplus is Fe and unavoidable impurities; And the content of Cr, Mo, Nb satisfies Cr+Mo+Nb 〉=0.35wt.%; The content of Cr, Mo satisfies Cr/Mo 〉=1.2.

More preferably, the chemical ingredients of described low-alloy high-strength high-toughness wear-resistant steel plate and content are: C:0.19～0.27wt.%, Si:0.30～0.90wt.%, Mn:0.80～1.6wt.%, P:＜0.030wt.%, S:＜0.010wt.%, Cr:0.40～0.8wt.%, Mo:0.15～0.40wt.%, Nb:0.010～0.040wt.%, B:0.0005～0.0040wt.%, Al:0.020～0.050wt.%, Ti:0.004～0.030wt.%, and surplus is Fe and unavoidable impurities; And the content of Cr, Mo, Nb satisfies Cr+Mo+Nb 〉=0.35wt.%; The content of Cr, Mo satisfies Cr/Mo 〉=1.2.

Most preferably, the chemical ingredients of described low-alloy high-strength high-toughness wear-resistant steel plate and content are: C:0.20～0.27wt.%, Si:0.30～0.75wt.%, Mn:0.80～1.5wt.%, P:＜0.030wt.%, S:＜0.010wt.%, Cr:0.40～0.8wt.%, Mo:0.15～0.40wt.%, Nb:0.015～0.040wt.%, B:0.0010～0.0040wt.%, Al:0.020～0.050wt.%, Ti:0.010～0.030wt.%, and surplus is Fe and unavoidable impurities; And the content of Cr, Mo, Nb satisfies Cr+Mo+Nb 〉=0.35wt.%; The content of Cr, Mo satisfies Cr/Mo 〉=1.2.

Another object of the present invention is to provide the manufacture method of this low-alloy high-strength high-toughness wear-resistant steel plate, and this method comprises makes that above-mentioned listed chemical ingredients is smelted, casting, heating, rolling, cooling, quenching and tempering step.Wherein in the heating steps, Heating temperature is 1050～1200 ℃; In the rolling step, start rolling temperature is 1000～1160 ℃, and finishing temperature is 840～1000 ℃, rolls the back air cooling, and described air cooling adopts stacking or cold bed cooling; In the quenching step, quenching temperature is Ac ₃+ 0～100 ℃; In the tempering step, tempering temperature is 150～350 ℃.

Composition design superiority of the present invention

The chemical ingredients of the present invention and other patent/patent application and content, carbon equivalent contrast see Table 1, and carbon equivalent numerical value calculates according to limit in the composition and obtains.

From steel grade cost angle analysis, patent/patent application CN1614069, FR2847272, JP2006506526, all added valuable alloying element Ni among EP1563104 and the US3761320, the related steel grade of all the other patents has also added more alloying element, has increased the production cost of steel.The designed steel grade of the present invention except B, the Al, Ti and the Nb that contain a spot of Si, Mn and Cr and trace, only contains a spot of Mo, and steel grade involved in the present invention has cost advantage.

From composition system angle analysis, related composition system of patent JP2006506526 and present patent application are similar, but its related steel plate hardness is only between 280HB and 450HB, and the related steel plate hardness of this patent is much higher than the related steel plate hardness of patent JP2006506526 more than 450HB.

Steel grade involved in the present invention is by the science design of element kind and content thereof, adding the coupling that has realized high-strength, hardness and high tenacity on a small amount of alloying element basis, improved the wear resistance of steel.

Carbon equivalent is the judgement index of steel welding property, and Ceq is low more, and weldability is good more, otherwise then weldability is poor more.Composition of the present invention, carbon equivalent and other wear resisting steel composition, carbon equivalent contrast see Table 1, and carbon equivalent numerical value calculates according to limit in the composition and obtains.

As known from Table 1, the Ceq value of the low-alloy high-strength high-toughness wear-resistant steel kind that the present invention relates to is 0.60, and the Ceq value minimum of the related steel grade of other patent of invention is 0.80.The Ceq of CN1189542, CN1865481, the related wear-resisting steel grade of US3761320 patent is less than 1.00, and the Ceq of all the other steel grades is all more than or equal to 1.00.The Ceq of the related steel grade of CN1099810 has reached 2.85.Steel grade involved in the present invention has welding property preferably.

Below, the chemical ingredients of low-alloy high-strength high-toughness wear-resistant steel plate involved in the present invention is done as being described in detail.

Carbon: content is controlled in 0.15～0.27wt% scope.Carbon is the most important element of hardening capacity that influences steel, can significantly improve the hardening capacity of steel.The solubleness of carbon in austenite is very big, plays the solution strengthening effect, can improve the intensity and the hardness of steel, and then improves the wear resistance of steel.But carbon is unfavorable to the toughness and the welding property of steel.Carbon content is high more, and toughness and welding property are poor more.Suitably control the carbon content in the steel, guarantee the toughness and the welding property of steel plate when can obtain higher-strength and hardness.

Silicon: silicon dwindles austenite and encloses mutually, improves the quenching temperature of steel.In the hypoeutectoid steel, the critical cooling velocity of steel reduces with the increase of silicone content.Add silicon in the wear resisting steel involved in the present invention, reduced the critical cooling velocity of steel, make final product form the martensitic stucture of refinement.Silicon is solid-solubilized in hardness and the intensity that improves them in ferrite and the austenite, yet the too high meeting of silicone content causes the toughness of steel sharply to descend.Consider that simultaneously silicon is stronger than iron with the avidity of oxygen, be easy to generate low-melting silicate during welding, increased the flowability of slag and deposite metal, influence weldquality.Therefore take all factors into consideration the influence of silicon to hardening capacity, intensity, toughness and welding property, the adding among the present invention is no more than the silicon of 0.2～1.0wt.%.

Manganese: manganese enlarges the austenite phase region that carbon iron balance is enclosed mutually, and the ability of stable austenite tissue is only second to nickel.Manganese increases the hardening capacity of steel strongly, reduces martensite transformation temperature, reduces the critical cooling velocity of steel.Manganese and iron form sosoloid, improve ferrite and austenitic hardness and intensity.In wear-resisting steel plate, add hardness and the wear resistance that manganese will increase steel.When but manganese content is higher, the tendency of the grain coarsening of making is arranged, and increase the crisp susceptibility of tempering of steel.For the wear-resisting steel plate of modifier treatment, needing on the one hand increases the hardness that manganese content improves steel plate, need control the temper brittleness that manganese content reduces steel plate on the other hand.Add the manganese that is no more than 0.8～1.8wt.% in the steel grade involved in the present invention, utilize the effect of manganese in wear resisting steel better.

Chromium: chromium content is controlled in 0.2～1.0wt.% scope.Chromium has the hardening capacity of solution strengthening, raising steel, the effects such as temper resistance of increase steel.Chromium solubleness in austenite is very big, strengthens austenite but does not reduce toughness.Chromium in steel, can form (Fe, Cr) ₃C, (Fe, Cr) ₇C ₃(Fe, Cr) ₂₃C ₇Etc. multiple carbide, improve intensity and hardness.Chromium can stop or slow down separating out of carbide and assemble when tempering, can improve the temper resistance of steel.

Molybdenum: content is controlled in 0.10～0.40wt.% scope.Molybdenum can crystal grain thinning, improves intensity and toughness.Molybdenum in steel, be present in sosoloid mutually with carbide mutually in, therefore, contain the effect that molybdenum steel has solution strengthening and carbide dispersion-strengthened simultaneously.Molybdenum is the element that reduces temper brittleness, can improve tempering and stablize.

Niobium: content is controlled in 0.010～0.040wt.% scope.Niobium can hinder austenite recrystallization, separates out NbC refinement ferrite crystal grain, improves intensity and toughness.Niobium can improve the temper resistance of steel, reduces the temper brittleness of steel.

Aluminium: aluminium and nitrogen in steel can form the AlN particle of tiny indissoluble, the crystal grain of refinement steel.When the aluminium of solid solution surpassed certain value in the steel, the austenite crystal of steel held the body alligatoring of growing up on the contrary.But the crystal grain of aluminium refinement steel, fixedly nitrogen in the steel and oxygen alleviate the susceptibility of steel to breach, reduce or eliminate the aging phenomenon of steel, and improve the toughness of steel.The aluminium of trace does not have remarkable influence to welding property.Aluminium reduces austenitic stability, the condensate depression when reducing austenitic transformation, and the hardening capacity of reduction steel improves the critical hardening speed of cooling.Take all factors into consideration the effect of aluminium, the aluminium content of wear-resisting steel plate involved in the present invention is no more than 0.020～0.060wt.%.

Titanium: titanium is one of strong carbide forming element, forms trickle TiC particle with carbon.The TiC particle is tiny, is distributed in crystal boundary, reaches the effect of crystal grain thinning, and harder TiC particle improves the wear resistance of steel.Titanium is a ferritisey, and can be solid-solubilized in raising ferrite intensity in the ferrite.Titanium can reduce steel 250 ℃～400 ℃ temper brittleness.If titanium and boron add jointly, will obviously reduce Low-Temperature Temper Brittleness.Quenching temperature improves, and TiC dissolved mark is more, quenches in the drawing process of back, and TiC disperse again separates out, and increases the temper resistance of steel.Comprehensive titanium is to steel phase transformation and Effect on Performance, and the titanium content that the present invention relates to wear resisting steel is controlled to be 0.004～0.030wt.%

Boron: boron increases the hardening capacity of steel.Boron is quenched to not influence of anti-temper softening effect behind the martensite to steel, and boron-containing steel need be taked lower tempering temperature and short tempering time.After the low-temperaturetempering, whether the intensity of boron-containing steel more or not intensity height.Boron-containing steel is in tempering more than 500 ℃, and its impelling strength is lower than not boron-containing steel, 300 ℃ of left and right sides tempering, and impelling strength is higher than not boron-containing steel.Boron content in the steel surpasses 0.007%, will cause hot-short phenomenon, influences the hot workability of steel.The boron that adds 0.0005～0.0040wt.% in the steel grade involved in the present invention is to bring into play its optimum utility in wear-resisting steel grade.

Phosphorus and sulphur: in wear resisting steel, sulphur and phosphorus are harmful element, and their content must strictly be controlled, and phosphorus content is less than 0.030wt.% in the steel grade involved in the present invention, and sulphur content is less than 0.010wt.%.

Manufacturing approach craft control principle of the present invention

1, heating and rolling technology

Steel plate involved in the present invention is at 1050 ℃～1200 ℃ heating austenitizings.In the heat-processed, the carbide of the chromium in the steel, molybdenum, niobium and titanium dissolves in the austenite, separates out in rolling and process of cooling, improves product strength by refined crystalline strengthening and precipitation strength.Directly rolling after steel billet is come out of the stove, roll the back air cooling, technology is simple, has good feasibility and feasibility in big the production.

2, quenching and tempering process

Steel plate rolling cooling post-heating is to Ac ₃Quench after+0～100 ℃ of insulations.Austenite generation martensitic transformation during quenching, the lattice distortion that takes place during quenching causes steel plate inside to have internal stress.Internal stress can make steel plate add to deform man-hour and burst apart, and need carry out temper and could eliminate internal stress, to be fit to processing and service requirements.

Steel plate after the quenching is put into 150～350 ℃ of process furnace temper.During low-temperaturetempering, elemental silicon, chromium and molybdenum can improve the cementite formation temperature, thereby weaken Low-Temperature Temper Brittleness, and the present invention adopts the lesser temps tempering under selected composition system condition, guarantee that steel plate has good strong, hardness and toughness.

Beneficial effect of the present invention is as follows:

1, by rational designing chemical composition, reduce alloy content, and need not to add noble element such as nickel, raw materials cost is lower, and the wear-resisting steel plate that the present invention relates to has good economic benefits.

2, behind the optimization composition, reduced carbon equivalent.The present invention relates to wear-resisting steel plate and have good welding property, be fit to needs welded structure steel and use the field.

3, the present invention with steel plate quenching after low-temperaturetempering, eliminated the internal stress of back steel plate of quenching, and made steel plate that high toughness and strong, hardness be arranged.

4, because composition and technological design are reasonable, from implementation result, process system is looser, can produce stably manufactured on the line at steel plate.

5, the present invention's low-alloy high-strength high-toughness wear-resistant steel plate Brinell hardness of producing greater than 450HB, tensile strength greater than 1500MPa, yield strength greater than 1200MPa, unit elongation greater than 15%, ballistic work is greater than 80J, thickness of slab can reach 80mm, and the wear-resisting steel plate that as seen the present invention relates to has excellent comprehensive mechanical properties.

Description of drawings

Fig. 1 is the microstructure of embodiment 4 low-alloy high-strength high-toughness wear-resistant steel plates, and the microstructure of this steel plate is a martensite as seen from the figure;

Fig. 2 is the low-alloy high-strength high-toughness wear-resistant steel plate thick section hardness measured value of the embodiment of the invention 6.

Embodiment

Below for a more detailed description to the present invention in conjunction with the accompanying drawings with embodiment.These embodiment only are the descriptions to embodiment of the present invention, scope of the present invention are not had any restriction.

In a preferred implementation: in described heat-processed, Heating temperature is 1050～1200 ℃.

In another preferred implementation: start rolling temperature is 1000～1160 ℃, and finishing temperature is 840～1000 ℃, rolls the back air cooling.

In another preferred implementation: quenching temperature is Ac ₃+ 0～100 ℃, the back water-cooled of coming out of the stove.

In another preferred implementation: tempering temperature is 150～350 ℃, the back air cooling of coming out of the stove.

In another preferred embodiment: air cooling adopts stacking or cold bed cooling.

Embodiment 1

The chemical ingredients of low-alloy high-strength high-toughness wear-resistant steel plate of the present invention and compared steel 1 (JP2006506526) is as shown in table 2.Press chemical ingredients electric furnace or the converter smelting shown in the table 2, and be cast into continuously cast bloom or steel ingot, continuously cast bloom or steel ingot are heated to 1050 ℃, start rolling temperature is 1000 ℃, and finishing temperature is 840 ℃, and the Finished Steel plate thickness is 8mm, rolling back air cooling, quenching temperature is Ac ₃, tempering temperature is 150 ℃, stacking or cold bed cooling after the tempering.

Embodiment 2

Embodiment is with embodiment 1, and wherein Heating temperature is 1070 ℃, and start rolling temperature is 1030 ℃, and finishing temperature is 870 ℃, and the Finished Steel plate thickness is 15mm, and quenching temperature is Ac ₃+ 20 ℃, tempering temperature is 200 ℃, stacking or cold bed cooling after the tempering.

Embodiment 3

Embodiment is with embodiment 1, and wherein Heating temperature is 1080 ℃, and start rolling temperature is 1045 ℃, and finishing temperature is 880 ℃, and the Finished Steel plate thickness is 30mm, and quenching temperature is Ac ₃+ 30 ℃, tempering temperature is 220 ℃, stacking or cold bed cooling after the tempering.

Embodiment 4

Embodiment is with embodiment 1, and wherein Heating temperature is 1160 ℃, and start rolling temperature is 1120 ℃, and finishing temperature is 910 ℃, and the Finished Steel plate thickness is 40mm, and quenching temperature is Ac ₃+ 60 ℃, tempering temperature is 260 ℃, stacking or cold bed cooling after the tempering.

Embodiment 5

Embodiment is with embodiment 1, and wherein Heating temperature is 1180 ℃, and start rolling temperature is 1150 ℃, and finishing temperature is 950 ℃, and the Finished Steel plate thickness is 50mm, and quenching temperature is Ac ₃+ 100 ℃, tempering temperature is 350 ℃, stacking or cold bed cooling after the tempering.

Embodiment 6

Embodiment is with embodiment 1, and wherein Heating temperature is 1200 ℃, and start rolling temperature is 1120 ℃, and finishing temperature is 1000 ℃, and the Finished Steel plate thickness is 80mm, and quenching temperature is Ac ₃+ 70 ℃, tempering temperature is 250 ℃.Stacking or cold bed cooling after the tempering.

The chemical ingredients (wt%) and the Ceq of the low-alloy high-strength high-toughness wear-resistant steel plate of table 2 embodiment of the invention 1-6

Test example 1 mechanical property test

Low-alloy high-strength high-toughness wear-resistant steel plate to embodiment of the invention 1-6 carries out Mechanics Performance Testing, and test result sees Table 3.

The low-alloy high-strength high-toughness wear-resistant steel plate mechanical property of table 3 embodiment of the invention 1-6

As can be seen from Table 2 as seen, ductility steel plate involved in the present invention is lower than the Ceq of compared steel 1, so welding property is better; As can be seen from Table 3, embodiment of the invention 1-6 low-alloy high-strength high-toughness wear-resistant steel plate tensile strength is greater than 1500MPa, yield strength is greater than 1200MPa, unit elongation is greater than 15%, ballistic work is greater than 80J, low-alloy high-strength and high-toughness steel plate involved in the present invention has good mechanical property, steel plate hardness involved in the present invention apparently higher than with the hardness of compared steel 1 steel plate.

Test example 2 thickness of slab cross section hardness tests

By standard GB/T 4340-1999 the cross section hardness of the low-alloy high-strength high-toughness wear-resistant steel plate of the embodiment of the invention 6 is measured, observed value is seen Fig. 2.

As can be seen from Figure 2, the cross section hardness of low-alloy high-strength high-toughness wear-resistant steel plate involved in the present invention is even.

3 solderability tests of test example

Low-alloy high-strength high-toughness wear-resistant steel plate to the embodiment of the invention 4 carries out welding performance test (little iron grinds test), and test-results is as shown in table 4.As shown in Table 4, crackle does not appear in the embodiment of the invention 4 steel plates postwelding under 150 ℃ of preheating condition, and steel plate of the present invention has good welding property.

The low-alloy high-strength high-toughness wear-resistant steel plate welding performance test result of table 4 embodiment of the invention 1

4 cut resistance tests of test example

Cut resistance test is carried out on the ML-100 grain-abrasion testing machine.During the intercepting sample, the axis normal that makes sample is in surface of steel plate, and the wearing surface of sample is the rolling surface of steel plate.Sample is processed into step-like right cylinder on request, and part of detecting is of a size of The jig retained part is of a size of Use the alcohol wash sample before the test, dry up with blower then, on the balance of ten thousand/precision, weigh, record sample weight, then be installed on the spring chuck as original weight.With granularity is 80 purpose sand paper, tests under the effect of 42N load.Test back is because the wearing and tearing between sample and sand paper, and the sample spiral-line that draws on sand paper stops the length that radius calculates spiral-line according to the initial sum of spiral-line, and calculation formula is

$S = \frac{π (r_{1}^{2} - r_{2}^{2})}{a}$

r ₁Be the start radius of spiral-line, r ₂Be the termination radius of spiral-line, a is the amount of feed of spiral-line.Each experiment is weighed and is averaged for three times, calculates weightlessness then, represents the wear rate (mg/M) of sample with every meter weightlessness.

Low-alloy high-strength high-toughness wear-resistant steel plate to the embodiment of the invention 5 carries out cut resistance test.The hardness that the present invention relates to the production of steel grade and Sweden SSAB company is that HARDOX500 (compared steel 2) the wear resisting steel wearing test of 500HB the results are shown in Table 5.

The wear test result of wear-resisting steel plate that table 5 the present invention relates to and HARDOX500 wear-resisting steel plate

Can find out that from table 5 the HARDOX500 grade wear-resisting steel plate polishing machine that the present invention relates to low-alloy high-strength high-toughness wear-resistant steel plate and the production of SSAB company is suitable, have the excellent abrasive energy.

Claims

1. low-alloy high-strength high-toughness wear-resistant steel plate, it is characterized in that, the chemical ingredients of described low-alloy high-strength high-toughness wear-resistant steel plate and content are: C:0.15～0.27wt.%, Si:0.20～1.0wt.%, Mn:0.80～1.8wt.%, P:＜0.030wt.%, S:＜0.010wt.%, Cr:0.20～1.0wt.%, Mo:0.10～0.40wt.%, Nb:0.010～0.040wt.%, B:0.0005～0.0040wt.%, Al:0.020～0.060wt.%, Ti:0.004～0.030wt.%, and surplus is Fe and unavoidable impurities; And the content of Cr, Mo, Nb satisfies Cr+Mo+Nb 〉=0.35wt.%; The content of Cr, Mo satisfies Cr/Mo 〉=1.2.

2. low-alloy high-strength high-toughness wear-resistant steel plate according to claim 1, it is characterized in that, the chemical ingredients of described low-alloy high-strength high-toughness wear-resistant steel plate and content are: C:0.17～0.27wt.%, Si:0.30～1.0wt.%, Mn:0.80～1.8wt.%, P:＜0.030wt.%, S:＜0.010wt.%, Cr:0.40～1.0wt.%, Mo:0.15～0.40wt.%, Nb:0.010～0.040wt.%, B:0.0005～0.0040wt.%, Al:0.020～0.060wt.%, Ti:0.004～0.030wt.%, surplus is Fe and unavoidable impurities; And the content of Cr, Mo, Nb satisfies Cr+Mo+Nb 〉=0.35wt.%; The content of Cr, Mo satisfies Cr/Mo 〉=1.2.

3. low-alloy high-strength high-toughness wear-resistant steel plate according to claim 2, it is characterized in that, the chemical ingredients of described low-alloy high-strength high-toughness wear-resistant steel plate and content are: C:0.19～0.27wt.%, Si:0.30～0.90wt.%, Mn:0.80～1.6wt.%, P:＜0.030wt.%, S:＜0.010wt.%, Cr:0.40～0.8wt.%, Mo:0.15～0.40wt.%, Nb:0.010～0.040wt.%, B:0.0005～0.0040wt.%, Al:0.020～0.050wt.%, Ti:0.004～0.030wt.%, surplus is Fe and unavoidable impurities; And the content of Cr, Mo, Nb satisfies Cr+Mo+Nb 〉=0.35wt.%; The content of Cr, Mo satisfies Cr/Mo 〉=1.2.

4. low-alloy high-strength high-toughness wear-resistant steel plate according to claim 3, it is characterized in that, the chemical ingredients of described low-alloy high-strength high-toughness wear-resistant steel plate and content are: C:0.20～0.27wt.%, Si:0.30～0.75wt.%, Mn:0.80～1.5wt.%, P:＜0.030wt.%, S:＜0.010wt.%, Cr:0.40～0.8wt.%, Mo:0.15～0.40wt.%, Nb:0.015～0.040wt.%, B:0.0010～0.0040wt.%, Al:0.020～0.050wt.%, Ti:0.010～0.030wt.%, surplus is Fe and unavoidable impurities; And the content of Cr, Mo, Nb satisfies Cr+Mo+Nb 〉=0.35wt.%; The content of Cr, Mo satisfies Cr/Mo 〉=1.2.

5. the manufacture method of the arbitrary described low-alloy high-strength high-toughness wear-resistant steel plate of claim 1 to 4, comprise make that the arbitrary listed chemical ingredients of claim 1 to 4 is smelted, casting, heating, rolling, cooling, quenching and tempering step;

In described heating steps, Heating temperature is 1050～1200 ℃;

In rolling step, start rolling temperature is 1000～1160 ℃, and finishing temperature is 840～1000 ℃, rolls the back air cooling;

In the quenching step, quenching temperature is Ac ₃+ (0～100) ℃;

In tempering step, tempering temperature is 150～350 ℃.

6. the manufacture method of low-alloy high-strength high-toughness wear-resistant steel plate according to claim 5, wherein said air cooling adopt stacking or cold bed cooling.