CN101962738A - Superfine carbide high-alloy tool steel shear-steel splicing mechanical blade - Google Patents

Abstract

The invention relates to the technical field of mechanical blades, in particular to a superfine carbide high-alloy tool steel shear-steel splicing mechanical blade which is manufactured by the steps of: firstly, manufacturing superfine carbide high-alloy tool steel shear-steel, wherein the shear-steel comprises the following components in percentage by weight: 0.52-0.62 percent of C, 0.40-0.60 percent of Si, 0.25-0.50 percent of Mn, 5.2-6.2 percent of Cr, 2.20-2.70 percent of W, 1.40-1.70 percent of Mo, 0.40-0.50 percent of V, 0.18-0.30 percent of Co or Ni, less than or equal to 0.015 percent of S, less than or equal to 0.02 percent of P and the balance of Fe; remelting electroslag by adopting an electric induction furnace or the electric induction furnace, forging and rolling at 870-1,100 DEG C; manufacturing a mechanical blade on a low-carbon steel plate by adopting high-temperature non-oxidation pressure rolling and splicing; and finally, annealing, quenching, tempering. The invention improves the yield of semi-finished products of the splicing procedure.

Description

The superfine carbide high alloy tool steel shear-steel mechanical bit of splicing

Technical field

The present invention relates to the preparing technical field of mechanical bit, especially a kind of superfine carbide high alloy tool steel shear-steel mechanical bit of splicing.

Background technology

The woodworking machine blade is the thin edged knife tool, and point of a knife need bear the huge impact load, in the relative movement of timber and blade, producing violent surface of friction can make point of a knife heat up, so blade material is not only wear-resisting, and want heat-resisting preventing to soften, in cutting, keep hardness.And carbide refinement could keep the good sharpness of point of a knife in the shear-steel, just can make the wood plate surface of machining bright and clean level and smooth.Along with the development of wood processing industry, requirement has than high-carbon low-alloy steel mechanical bit and has longer work-ing life and better processing quality, and in order to realize this target, we are devoted to the research and development of the high quality steel of superfine carbide for many years always.A kind of series superfine carbide high alloy tool steel is disclosed as Chinese patent CN100469938C, its method of design integrated use balance each other calculation of thermodynamics and carbide phase transformation law, the calculating of bound energy on electronics/atom level, thermal treatment process and quenching and tempered-hardness Calculation Method, intensity and toughness to new steel grade have been made prediction, the timber slicing cutter made from this invention has high rigidity, high-wearing feature and high cutting edge sharpness, adopt the splice processing requirement of process implementing and control of high temperature non-oxidation pressure rolling but still can not satisfy, can not improve the yield rate of product completely.

Summary of the invention

In order to overcome the deficiency that the existing mechanical blade can not improve the yield rate of product completely, the invention provides a kind of superfine carbide high alloy tool steel shear-steel mechanical bit of splicing.

One of proposition of the present invention aims to provide a kind of superfine carbide high alloy medium carbon tool steel shear-steel.Its composition principle of design is that (1) reasonably C, Cr, W, Mo, V content guarantee carbide refinement, add a spot of Co or Ni to improve matrix with the bonding force of carbide and hinder atomic diffusion and promote the refinement carbide, it is stronger wherein to contain the Co bonding force, it is stronger to contain Ni reduction surface oxidation decarburizing tendency, can select according to blade type; (2) rational Cr, W, Mo, V ratio utilize the variation of dissimilar carbide phase constituents to make it precipitation hardening near tempering secondary hardening maximum hardness district, obtain high tempered-hardness; Massive carbide when (3) having eliminated molten steel solidification has fully guaranteed high yield strength and impact toughness index, prevents that burr and chipping from appearring in blade cutting edge in the usage period.

Two of proposition of the present invention aims to provide a kind of high alloy tool steel shear-steel that meets above-mentioned shear-steel composition mechanical bit of splicing, and the high temperature non-oxidation pressure rolling of the employing technology of splicing is the technology of patent ZL200510028805.8.Its performance characteristics is that (1) shear-steel has good hot rolling, and shear-steel and matrix bond belong to metallurgical binding when high temperature hot rolling edge steel, have good binding; (2) utilize thin edged knife tool cutting edge sharpness to depend on the mechanism of suitable quenching undissolved carbide quantity and degree of refinement and high tempered martensite matrix yield strength, make to reach high level in its cutting ability and work-ing life.

The technical solution adopted for the present invention to solve the technical problems is: a kind of superfine carbide high alloy tool steel shear-steel mechanical bit of splicing, at first prepare the superfine carbide high alloy tool steel shear-steel, and described superfine carbide high alloy tool steel shear-steel contains (wt%) C0.52～0.62, Si0.40～0.60, Mn0.25～0.50, Cr5.2～6.2, W2.20～2.70, Mo1.40～1.70, V0.40～0.50, Co or Ni are 0.18～0.30, S≤0.015, P≤0.02, the Fe surplus; Its preparation comprises adopts induction furnace or induction furnace+esr and 870 ℃～1100 ℃ forging rolling processing steps thereof;

Next adopts the pressure rolling of high temperature non-oxidation to splice and manufacture mechanical bit on mild steel plate;

Anneal at last, the quenching and tempering processing step, its processing condition are:

(1) annealing is heated 830 ℃～840 ℃, is incubated cold with stove after 4～6 hours;

(2) quench, heat 1010 ℃～1050 ℃, oil cooling or air cooling behind the 1.2 minutes/mm of insulation;

(3) tempering is heated 520 ℃～560 ℃, is incubated 2～4 hours.

The invention has the beneficial effects as follows, splice mechanical bit relatively with existing high alloy tool steel, the invention has the advantages that Cr, W, Mo, V alloy total amount and the C content of (1) shear-steel are lower than the content of DM6S class steel (patent No. ZL200710010536.1), be convenient to the pressure rolling of high temperature non-oxidation splice process implementing and control, improved the half-finished qualification rate of the operation of splicing; (2) ratio of the Cr of shear-steel, W, Mo, V is reasonable, eliminated that common massive carbide makes it to reach complete super-refinement in present general high quality steel and the special high quality steel shear-steel mechanical bit, contain the cohesive action of suitable quenching undissolved carbide quantity and a small amount of Co or Ni after the thermal treatment, make the cutting edge of cutter sharp and wear-resisting, the wood working face is brighter and cleaner; (3) substitute low, the Medium Alloy Steel commonly used at present mechanical bit of splicing, its wear resistance is higher, longer service life; Its shear-steel characteristic is applicable to the various wood working of soft or hard, both can be used as the slicing cutter and also can be used as the rotary-cut cutter.This superfine carbide high alloy tool steel shear-steel is containing of independent research of micro-Co or the Cr-W-Mo-V high alloy tool steel of Ni, has carbide super-refinement (residue of quenching carbide size 0.24 μ m) and tempering secondary hardening hardness height (62～64HRC) characteristic; The high temperature non-oxidation pressure rolling of the adopting technology of splicing is the technology of existing patent ZL200510028805.8.This mechanical bit has been eliminated the massive carbide in the mechanical bit shear-steel both at home and abroad fully, substitutes the high quality steel commonly used at present mechanical bit of splicing, and its sharpness is higher, and the cutting wood plate surface is brighter and cleaner; Substitute low, the Medium Alloy Steel commonly used at present mechanical bit of splicing, its wear resistance is higher, and longer service life has a wide range of applications at wood working industry.

Description of drawings

The present invention is further described below in conjunction with drawings and Examples.

Fig. 1 (a) is the Fe-5.7Cr-2.45W-1.55Mo-0.45V-0.33Mn-0.5Si-0.24Co equilibrium phase diagram; (b) be the Fe-5.7Cr-2.45W-1.55Mo-0.45V-0.33Mn-0.5Si-0.24Ni equilibrium phase diagram;

Fig. 2 is a shear-steel scanned photograph after heat treatment;

Fig. 3 is quenching, tempered-hardness graphic representation;

Fig. 4 (a) is shear-steel quenching metallograph; (b) be that splice annealing metallograph, (c) is through the splice transversary synoptic diagram of mechanical bit of high temperature non-oxidation pressure rolling;

Fig. 5 is the splice vertical structure synoptic diagram of mechanical bit of superfine carbide high alloy tool steel shear-steel.

Among the figure, 1, shear-steel, 2, the place of splicing of shear-steel and soft steel, 3, soft steel.

Embodiment

A kind of superfine carbide high alloy tool steel shear-steel mechanical bit of splicing at first prepares the superfine carbide high alloy tool steel shear-steel, and described superfine carbide high alloy tool steel shear-steel contains (wt%) C0.52～0.62, Si0.40～0.60, Mn0.25～0.50, Cr5.2～6.2, W2.20～2.70, Mo1.40～1.70, V0.40～0.50, Co or Ni are 0.18～0.30, S≤0.015, P≤0.02, the Fe surplus; Its preparation comprises adopts induction furnace or induction furnace+esr and 870 ℃～1100 ℃ forging rolling processing steps thereof;

Next adopts the pressure rolling of high temperature non-oxidation to splice and manufacture mechanical bit on mild steel plate;

Anneal at last, the quenching and tempering processing step, its processing condition are:

(1) annealing is heated 830 ℃～840 ℃, is incubated cold with stove after 4～6 hours;

(2) quench, heat 1010 ℃～1050 ℃, oil cooling or air cooling behind the 1.2 minutes/mm of insulation;

(3) tempering is heated 520 ℃～560 ℃, is incubated 2～4 hours.

As Fig. 1～a kind of superfine carbide high alloy tool steel shear-steel shown in Figure 3.

Make shear-steel of the present invention, its chemical ingredients is as shown in table 1:

As shown in Figure 4 through the pressure rolling of high temperature non-oxidation splice mechanical bit structure and blade shear-steel and the position metallographic of splicing, its thermomechanical parameter such as table 2:

Carry out mechanical workout and thermal treatment after splicing, its thermal treatment process and technical indicator such as table 3:

Table 3 thermal treatment process and hardness, organizational standard

The mechanical bit manufacturing process of splicing route is:

Shear-steel forging rolling → annealing → blanking → smoothing → machining,

Cutter hub blanking → smoothing → channeling,

Non-oxidation welding → hot rolling is spliced,

Annealing → smoothing, ⑸ quenches, tempering, ⑹ smoothing → corase grind → planes slightly → sharpening → the mill back of the body → crop, ⑺ finish grind face → correct grinding slightly → essence smooths, ⑻ hole slot processing → tapping → essence is smoothed, ⑼ check → packing.

The mechanical bit of splicing of superfine carbide high alloy tool steel shear-steel as shown in Figure 5, its stock size such as table 4:

The design of the composition of shear-steel is to analyze the balance each other weave construction of calculation of thermodynamics of alloy system, Q-tempering hardness and thermal treatment temp calculate and alloy atom between on cohesive energy calculation and the basis that performance is associated and proposition, general condensed summary is as follows:

When (1) containing 0.18 ~ 0.3Co or Ni, at other compositions under similar circumstances, the equilibrium phase in the steel varies with temperature much at one, therefore, its thermal treatment process, microstructure and performance also much at one, as Fig. 1 (a) with (b).

(2) anneal between heating period at 830 ~ 840 ℃, M23C6 and M6C growth and decline each other cause the refinement basis; In 1010-1050 ℃ of quenching heat-processed, M23C6 dissolving and M6C dissolve gradually, separate out M7C3 and dissolve, and the MC local dissolution is also separated out again, and whole process all makes the residue carbide be tending towards refinement; The residue of quenching carbide mean sizes is 0.24 μ m; As shown in Figure 2.

(3) M23C6 that separates out in drawing process, M6C, MC ratio are suitable, make carbide phase constituent reasonable because of alloy ratio again, make M23C6 separate out postponement, MC separates out in advance, make the precipitation hardening effect concentrate on the tempering temperature interval, solid solution can promote precipitation to separate out in the Co or the Ni of matrix in addition, thereby, tempered-hardness is higher than quenching hardness 2 ~ 3HRC, can adopt higher tempering temperature to obtain good mechanical property; As shown in Figure 3.When Q-tempering hardness was 63HRC, the actual measurement transverse yield strength was 3620MPa, and impact toughness is 98J/cm2.

(4) solvent temperature of the MC carbide of most of high quality steel is greater than M6C, and near 1200 ℃, still, the solvent temperature of the MC carbide of this steel is lower than 1100 ℃ less than M6C.Non-equilibrium transformation generates massive carbide when both preventing molten steel solidification, keeps more quenching residue MC to prevent grain growth again, and its key is rational Cr, W, Mo, V alloy design proportion.

(5) also consider following factor during alloy designs: C content is higher than that high-temp plastic is low in limited time, and being lower than down in limited time, hardness reduces; Si content is higher than fragility increase in limited time and surface decarburization is increased the weight of, and being lower than down in limited time, intensity reduces; Contain the Mn amount and be higher than fragility increase in limited time, being lower than down in limited time, intensity reduces; Contain the Cr amount and be higher than remained austenite content increase in limited time and make tempering temperature depart from the maximum hardness point, being lower than down in limited time, quenching hardness reduces; Contain the W amount and be higher than high-temp plastic reduction in limited time, being lower than down in limited time, tempered-hardness reduces; Contain Mo amount and be higher than that high-temp plastic is low in limited time, be lower than the tempered-hardness of prescribing a time limit down and obviously reduce; V content is higher than in limited time and occurs massive carbide easily, and being lower than down in limited time, tempered-hardness reduces; Ni content is higher than the nodularization difficulty of annealing in limited time, and being lower than down in limited time, intensity reduces; Containing Co amount, to be higher than thermal treatment in limited time unfavorable, is lower than down that matrix and carbide bonding force do not obtain raising in limited time.

(6) evaluation to thermal treatment process is, is below or above annealing temperature, and annealed structure is bad or annealing hardness is higher; Quenching temperature surpasses the upper limit, and the too high hardness that causes of grain coarsening and residual austenite reduces; Tempering temperature is higher than upper limit hardness and reduces, and it is too high to be lower than the lower limit residual austenite.

Shear-steel quenching, tempering temperature and experiment of hardness result are as shown in table 5:

The invention process is for example shown in table 6 and the table 7:

Above embodiment is only for the usefulness that the present invention is described, but not limitation of the present invention, each manufacturing enterprise or company in the mechanical bit field, may make various process programs and application, therefore all adopt the equivalent technical solutions of shear-steel composition of the present invention also should belong to category of the present invention, all should be that claim limits.

Claims (1)

1. superfine carbide high alloy tool steel shear-steel mechanical bit of splicing, it is characterized in that, at first prepare the superfine carbide high alloy tool steel shear-steel, described superfine carbide high alloy tool steel shear-steel contains (wt%) C0.52～0.62, Si0.40～0.60, Mn0.25～0.50, Cr5.2～6.2, W2.20～2.70, Mo1.40～1.70, V0.40～0.50, Co or Ni are 0.18～0.30, S≤0.015, P≤0.02, Fe surplus, its preparation comprise employing induction furnace or induction furnace+esr and 870 ℃～1100 ℃ forging rolling processing steps thereof;

Next adopts the pressure rolling of high temperature non-oxidation to splice and manufacture mechanical bit on mild steel plate;

Anneal at last, the quenching and tempering processing step, its processing condition are:

(1) annealing is heated 830 ℃～840 ℃, is incubated cold with stove after 4～6 hours;

(2) quench, heat 1010 ℃～1050 ℃, oil cooling or air cooling behind the 1.2 minutes/mm of insulation;

(3) tempering is heated 520 ℃～560 ℃, is incubated 2～4 hours.

Images