CN106319358A - High-carbon steel wire rod for filament drawing and production method thereof - Google Patents

Abstract

The invention provides a high-carbon steel wire rod for filament drawing and a production method thereof. The high-carbon steel wire rod comprises, by weight, 0.69-0.84% of C, 0.30-0.60% of Mn, 0.10-0.40% of Si, less than or equal to 0.010% of P, less than or equal to 0.010% of S, less than or equal to 0.0010% of Ti, 0.0005-0.0020% of total aluminum, 0.0015-0.0025% of total oxygen, greater than or equal to 0.0002% and less than or equal to 0.0007% of Mg and the balance Fe and unavoidable impurities. The production method comprises converter smelting, LF refining, continuous casting, continuous rolling and wire rod rolling. A high-carbon steel wire rod prepared from the above components through the production method has tensile strength of 1050-1250MPa, an area reduction ratio of 35-50%, inclusion width less than or equal to 10 microns and an inclusion length-width ratio greater than 3.

Description

High-carbon steel wire rod and production method thereof for fine drawing

Technical field

The invention belongs to high-carbon steel field, particularly for below 0.2mm fine drawing High-carbon steel wire rod and production method thereof, wherein high-carbon steel wire rod is carbon content more than 0.6%.

Background technology

Along with the fast development of the equipment manufactures such as automobile, simultaneously for loss of weight and safe examining Considering, wire fabrication presents obvious high strengthening trend, and current filament strength reaches as high as More than 4000MPa, but to obtain the highest intensity, in addition to carrying out composition adjustment, the most right The processing characteristics of wire rod proposes higher requirement.In order to make wire rod meet while improving intensity The needs of drawing processing, generally to carry out two aspect work simultaneously, and one is wire rod composition and tissue Optimizing, alloying and rolling mill practice such as steel control；Two is to improve Control and Inclusion Removal level, subtracts Few the amount of inclusions, improves field trash morphotropism.

" high intensity, high tenacity carbon steel wire rod with high and manufacture method thereof " (ZL200480002971.4) Providing a kind of carbon content 0.6～the high-carbon steel wire rod of 0.95%, it is mainly characterized in that logical Cross interpolation Zr, utilize Zr oxide as heterogeneous nuclei, thus reduce segregation, thinning microstructure, Obtain intensity and mate preferable high-carbon steel wire rod with plasticity and toughness.This patent be mainly characterized by use The method of Oxide Metallurgy obtains the tissue being beneficial to deformation, if but to there is morphotropism in steel bad Bulky grain is mingled with, and is prone to produce at the two ends of Inclusions Along deformation direction fine fisssure in deformation process Stricture of vagina also ultimately results in fracture of wire, in this way it cannot be guaranteed that wire rod necessarily have good can drawing Property.

" carbon steel wire rod with high of excellent processability " (application number: 201080003183.2) provides A kind of contain 0.6～the Mn of the Si of the carbon of 1.1%, 0.1～0.5%, 0.2～0.6%, 0.004～0.015% The Cr of S, 0.02～0.05%, the high-carbon of Al of the P of less than 0.02% and less than 0.003% Steel wire rod.This kind of wire rod obtains the pearlite colony chi of specified size by special rolling mill practice Very little and sulphide inculsion spacing distance, so that this wire rod has good processing characteristics.Meanwhile, By controlling the content of FeO in iron scale, the thickness making iron scale is 6～15um, fortune Defeated process tack is good, comes off functional during machinery dephosphorization.This patent is controlled at wire rod tissue System and Control and Inclusion Removal aspect all work, but only discuss between sulfide in terms of field trash Away from control, and actually oxide to be mingled with the impact on wire rod processing characteristics bigger, this patent Shortcomings in this respect.

" there is cutting steel wire wire rod and the production technology thereof of good drawing property " (Title: (EN)WIRE ROD FOR A SAW WIRE WITH SUPERIOR WIRE DRAWABILITY AND A MANUFACTURING METHOD THEREOF； Publication Number:1020110075625) describe a kind of cutting steel wire wire rod Production method.Field trash Al in this wire rod₂O₃Content is not more than 50%.The method is introduced in essence Refining process uses carbon line carburetting, it is ensured that the stability of carbon content.In tundish smelting process, adopt With stopper rod flow control, and Al content is used to be not more than resistance to as big tank of the fire-resistant employing of 1% Material.This patent improves stablizing of the processing characteristics of wire rod by raising wire rod ingredient stability Property, notice the control problem that oxide is mingled with simultaneously.But the complicated component that oxide is mingled with, Only control the Al in field trash₂O₃Content sometimes be not enough to obtain good being mingled with of morphotropism Thing.

Summary of the invention

It is an object of the invention to overcome the problems referred to above and deficiency to provide a kind of and draw for filament The high-carbon steel wire rod pulled out and production method thereof, by using rational alloying component and smelter Skill, controls the content of MgO in the field trash in wire rod, makes field trash have good deformation Property, and control wire rod pearlite size simultaneously, improve the processing characteristics of wire rod, meet user and enter The use requirement of row fine drawing.

In order to be developed for the high-carbon steel wire rod of below 0.2mm fine drawing, its medium and high carbon steel Wire rod is carbon content more than 0.6%, and the present invention is by suitably controlling the chemical composition of wire rod, knot Close converter, refine, continuous casting and rolling mill practice control, and have both met steel grade to intensity, plasticity Requirement, meets again high-carbon steel wire rod to inclusion size and the requirement of morphotropism.

The object of the invention is realized in:

A kind of high-carbon steel wire rod chemical composition for fine drawing is: [C]: 0.69%～ 0.84%, [Mn]: 0.30%～0.60%, [Si]: 0.10%～0.40%, [P]≤0.010%, [S]≤0.010%, [Ti]≤0.0010%, full aluminum: 0.0005%-0.0020%, total oxygen: 0.0015%-0.0025%, 0.0002%≤[Mg]≤0.0007%, remaining is ferrum and inevitable Impurity.

Carbon is the main intensified element in steel, and carbon content is the highest, wire rod and the tensile strength of steel wire The biggest.But too high carbon content causes wire rod at the wire broken rate of drawing process and layering occur Phenomenon increases.Therefore, in steel carbon content control at 0.69%-0.84%.

Manganese is also a kind of element improving wire rod intensity, and is conducive to eliminating the illeffects of sulfur, Therefore add what a certain amount of manganese was a need for.But manganese element is the tightest in the segregation of process of setting Weight, in steel, Fe content is unsuitable too high.Therefore, in steel, Fe content controls 0.30%～0.60%.

Silicon is at the main deoxidant element of smelting process for the high-carbon steel wire rod of fine drawing.Silicon Content is low will cause deoxygenation of liquid steel not enough；But, too high silicone content causes residual oxygen in steel Thing is mingled with thick, unfavorable to the application performance of steel.Therefore, in steel, silicone content controls 0.10%-0.40%.

Phosphorus sulfur is all objectionable impurities element in steel, it is desirable to wire rod [P]≤0.010%, [S]≤ 0.010%, in the case of not causing other influences, the lowest more good.

Titanium is prone to form titanium with nitrogen in high-carbon steel and is mingled with, and causes steel wire fracture, therefore its content Require [Ti]≤0.0010%.

Aluminum content and total oxygen content span of control closely related with steel inclusion composition, too high Or the too low fusing point that all can cause steel inclusion raises, deformation performance declines.Therefore complete in steel Aluminum content requirement controls at 0.0015%-0.0025% at 0.0005%-0.0020%, total oxygen content.

Magnesium in wire rod has the effect of deoxidation and desulfurization, but for the height for fine drawing For carbon steel, magnesium easily Al and O in steel is combined formation indeformable magnesium aluminate spinel folder Miscellaneous, therefore should strictly control the content of magnesium in steel, for the present invention, it is desirable in steel 0.0002% ≤ [Mg]≤0.0007%.

For the production method of the high-carbon steel wire rod of fine drawing, including converter smelting, LF essence Refining, continuous casting, tandem rolling and wire rod rolling:

(1) converter smelting: converter smelting uses tapping steel with high carbon, and endpoint carbon content of converter is the lowest In 0.5%, thus reduce furnace rear carbon increasing amount, alleviate the degree of oxidation of molten steel simultaneously, reduce by In the molten steel nitrogen pick-up that furnace rear carburetting and deoxidation cause.Silicon manganese dioxidation is used, it is to avoid make after Converter With the strong deoxidizer such as Al, Ti, it is desirable in the silicomangan of use, Mg constituent content is not more than 0.02%, it is to avoid in steel, introduce too much Mg, form indeformable magnesium aluminate spinel and be mingled with；

(2) LF refine: in order to ensure refining slag homogenization of composition and fully to carry out slag anti- Should discharge with the floating of field trash, refinery practice temperature should control at 1550 DEG C-1640 DEG C, time Between 60-80 minute.Refine terminal molten steel oxygen activity controls in (15-30) × 10^-6Between, molten steel Acid-soluble aluminum content controls between 0.0010%-0.0020%, and content of magnesium controls Between 0.0002%-0.0007%, require that the content of MgO in refining slag controls simultaneously Between 5%-12%, by affecting the reaction of molten steel and top slag molecular balance and field trash and molten steel Balance, so that the content of MgO of steel inclusion controls between 3%-8%, makes oxygen in steel Compound entrained components is in low melting point district, improves the deformability that oxide is mingled with.Additionally, steel The Ti content of liquid not should be greater than 0.0010%, reduces the formation that TiN is mingled with as far as possible.

(3) continuous casting: employing bloom continuous casting, steel billet cross dimensions 280mm*380mm, Pulling rate is between 0.4m/min-0.7m/min, and the Metal in Tundish degree of superheat is not more than 25 DEG C.Logical Crossing the cast of low overheat low pulling rate, alleviate steel billet segregation, in minimizing steel, oxide is mingled with, titanium presss from both sides Miscellaneous grows up the time, reduces the size of field trash.

(4) tandem rolling and wire rod rolling: wire rod diameter 5mm-5.5mm, laying temperature 880 DEG C -910 DEG C, the wire rod after weaving silk is cooled fast to 600 DEG C～650 DEG C on Stevr rubs cooling line Carry out phase transformation, thus obtain sorbite tissue.

The feature of technical solution of the present invention is, by adjusting top when Mg content and refine in steel Slag ingredient, makes the content of MgO in steel inclusion be in proper range, so that field trash There is good morphotropism, improve the processing characteristics of high-carbon steel wire rod.Converter uses tapping steel with high carbon, Ensure time and temperature during refine and use special refining slag, casting process employing low overheat, Low pulling rate operates, and controls wire rod segregation.Quickly cool down to reduce the Soxhlet of wire rod after wire rod rolls Body sheet interlayer spacing.

The beneficial effects of the present invention is: raw according to the composition related in the present invention and production method The high-carbon steel wire rod produced, its tensile strength is 1050MPa-1250MPa, and reduction of area is 35%～50%, field trash width dimensions is not more than 10um, and field trash length-width ratio is more than 3, completely The foot demand of user.

Accompanying drawing explanation

Fig. 1 is the embodiment of the present invention 1 field trash pattern.

Fig. 2 is the embodiment of the present invention 2 field trash pattern.

Fig. 3 is the embodiment of the present invention 3 field trash pattern.

Fig. 4 is comparative example field trash pattern.

Detailed description of the invention

Below by embodiment, the present invention is further illustrated.

The embodiment of the present invention according to the component proportion of technical scheme, carry out smelting, continuous casting, rolling, Continuous annealing, smooth.The chemical composition of embodiment of the present invention wire rod is shown in Table 1.The present invention implements The main technologic parameters of example wire rod is shown in Table 2.The performance of embodiment of the present invention wire rod is shown in Table 3.

The chemical composition (wt%) of table 1 embodiment of the present invention steel

The main technologic parameters of table 2 embodiment of the present invention steel

The performance of table 3 embodiment of the present invention wire rod

Claims (2)

1. the high-carbon steel wire rod for fine drawing, it is characterised in that the composition of this wire rod is pressed Percentage by weight meter is as follows: [C]: 0.69%～0.84%, [Mn]: 0.30%～0.60%, [Si]: 0.10%～0.40%, [P]≤0.010%, [S]≤0.010%, [Ti]≤0.0010%, full aluminum: 0.0005%-0.0020%, total oxygen: 0.0015%-0.0025%, 0.0002%≤[Mg]≤ 0.0007%, remaining is ferrum and inevitable impurity.

2. a production method for the high-carbon steel wire rod for fine drawing described in claim 1, bag Include converter smelting, LF refine, continuous casting, tandem rolling and wire rod rolling, it is characterised in that:

(1) converter smelting: converter smelting uses tapping steel with high carbon, and endpoint carbon content of converter is the lowest In 0.5%, alleviate the degree of oxidation of molten steel simultaneously, reduce owing to furnace rear carburetting and deoxidation cause Molten steel nitrogen pick-up, after Converter use silicon manganese dioxidation, in silicomangan, Mg constituent content is little In 0.02%；

(2) LF refine: refining process temperature should control at 1550 DEG C-1640 DEG C, time 60-80 Minute, refine terminal molten steel oxygen activity controls in (15-30) × 10^-6Between, molten steel dissolved aluminum contains Amount controls between 0.0010%-0.0020%, and content of magnesium controls at 0.0002%-0.0007%, Require that the content of MgO in refining slag controls at 5%-12% simultaneously, so that steel inclusion Content of MgO control between 3%-8%, the Ti content of molten steel not should be greater than 0.0010%；

(3) continuous casting: employing bloom continuous casting, steel billet cross dimensions 280mm*380mm, Pulling rate is not more than 25 DEG C in 0.4m/min-0.7m/min, the Metal in Tundish degree of superheat；

(4) tandem rolling and wire rod rolling: wire rod diameter 5mm-5.5mm, laying temperature 880 DEG C -910 DEG C, the wire rod after weaving silk is cooled fast to 600 DEG C～650 DEG C.