CN106319178A

CN106319178A - Forging and thermal treatment technique for Cr12MoV steel

Info

Publication number: CN106319178A
Application number: CN201610717978.9A
Authority: CN
Inventors: 卢劲松
Original assignee: RUIAN JINLI MACHINERY MANUFACTURING Co Ltd
Current assignee: RUIAN JINLI MACHINERY MANUFACTURING Co Ltd
Priority date: 2016-08-25
Filing date: 2016-08-25
Publication date: 2017-01-11

Abstract

The invention discloses a forging and thermal treatment technique for Cr12MoV steel. The forging and thermal treatment technique specific for Cr12MoV steel comprises the following working procedures that a PLC four-point temperature-controlled regenerative heating furnace is selected and applied, and the heating process is divided into three stages, specifically, heating is carried out till the temperature is 550 DEG C firstly, the temperature is increased from 550 DEG C to 850 DEG C at a uniform speed, the temperature increasing speed is kept to be 80-90 DEG C per hour, the temperature is kept at 850 DEG C for eight hours, and then the temperature is increased to 1100-1150 DEG C; the initial forging temperature is 1100-1150 DEG C, and the final forging temperature is 850-880 DEG C; oil or salt bath quenching is carried out till the temperature is 1100-1150 DEG C, and the temperature is preserved for 15 min; cooling is carried out; three sections of isothermal spheroidizing at the temperatures of 720 DEG C, 740 DEG C and 720 DEG C separately are carried out, and each section lasts for two hours; tempering is carried out at the temperature of 220 DEG C; and the steel is discharged out of a furnace and placed in air for natural cooling. Processing molds for the technique can make carbide refined, edges and corners round and Austenite matrixes superfine, and high hardness and compressive strength are achieved.

Description

The forging of Cr12MoV steel and Technology for Heating Processing

Technical field

The technique that the present invention relates to a kind of technical field of forging, is specifically related to a kind of Forging Technology.

Background technology

The wide variety of high Gr Light deformation cold work die steel of Cr12MoV Gang Shi China, belongs to ledeburite steel, eutectic in tissue Carbide dendrite is the most flourishing, and the feature of these carbides is that fusing point is high, hard and crisp, plasticity extreme difference.The poor thermal conductivity of this steel, On the one hand in forging process, there are two contradictory elements in action, are that the strike of forging hammer makes carbide be smashed to beat Broken, if final forging temperature is too low, austenite gross distortion and produce processing hardening, on the other hand be that forging temperature is higher, eutectic carbon At compound heap, fusing point is relatively low, and hammering is too quickly, and forging intensification makes workpiece localized micro district rise to more than eutectic melting temperature, leads Cause to organize overheated, burning, form implosion.Aborning, often due to traditional handicraft can not eliminate big block eutectic carbide or Serious net carbide so that use the mould that this material is made, uses less than expected number of times after upper machine, just produces and splits Stricture of vagina, during being continuing with, crackle extends rapidly, just makes mould invalidation to use less than expected number of times.This is always One thorny feeling bad of enterprise.In die manufacture, forging process plays conclusive effect to improving banded structure, Urgently improve.

Summary of the invention

In view of the deficiency of background technology, the technical problem to be solved is to provide one and makes carbide refinement, rib Angle rounding, and make forging and the Technology for Heating Processing of the Cr12MoV steel of austenite matrix super-refinement.

For achieving the above object, the technical scheme is that forging and the Technology for Heating Processing of Cr12MoV steel, It is characterized in that: for the technique that material is Cr12MoV steel, including following operation:

(1) selecting the recuperative heater of 4 temperature controls of PLC, its heating process is 3 processes, is first heated to 550 DEG C, by 550 DEG C are at the uniform velocity warming up to 850 DEG C, and keeping programming rate is 80-90 DEG C/h, is incubated 8 hours, then is warming up to 1100-at 850 DEG C 1150℃；

(2) initial forging temperature is 1100-1150 DEG C, and final forging temperature is 850-880 DEG C；

(3) oil or salt bath quenching are to 1100-1150 DEG C, are incubated 15min；

(4) cooling；

(5) 720 DEG C → 740 DEG C → 720 DEG C 3 sections of isothermal spheroidizings, every section of 2h are carried out；

(6) 220 DEG C of tempering；

(7) come out of the stove, be placed in natural cooling in air.

Using hexahedro pier to pull out method described Cr12MoV steel, pull out including three piers three, total forging ratio is 15.

Described Cr12MoV steel is used weight in the range of forging temperature 900 DEG C-1000 DEG C, uses during remaining forging Light hammer.

By using technique scheme, in technique, the higher quenching temperature of 1100-1150 DEG C is conducive to little bulk Dissolving and the change of big massive carbide wedge angle form of carbide, alleviates and to alleviate carbide quantity many and in wedge angle form Time easily cause stress concentrate adverse effect, reduce the fragility of mould, add toughness, and the distortion degree of steel is the least In the distortion that low temperature quenching produces；And the three sections of isothermal spheroidizings carried out subsequently eliminate net carbide and bulk tip-angled shape further Carbide also eliminates thick Structure Inheritance, and after finished heat treatment, grain size refines, becomes round up to 10-12 level, carbide particle, make The impact toughness of steel significantly improves, and is greatly prolonged the mold use life-span；In last tempering makes the remnants produced during quenching Stress is eliminated, and improves plasticity and the toughness of mould.And six sides forging method and forging medium temperature use weight side On the one hand formula, is avoided that the strike of forging makes carbide be smashed and smashes, austenite gross distortion and produce processing hardening, another Aspect is avoided, because hammering is too quickly, forging intensification makes workpiece localized micro district rise to more than eutectic melting temperature, causing organizing Heat, burning, the problem forming implosion.

Detailed description of the invention

Embodiment: for the technique that material is Cr12MoV steel, including following operation:

(3) oil or salt bath quenching are to 1100-1150 DEG C, are incubated 15min；

(4) cooling；

(6) 220 DEG C of tempering；

(7) come out of the stove, be placed in natural cooling in air.

The present embodiment, in technique, the higher quenching temperature of 1100-1150 DEG C is conducive to the dissolving of little massive carbide With the change of big massive carbide wedge angle form, alleviate and to alleviate carbide quantity many and easily cause stress during in wedge angle form The adverse effect concentrated, reduces the fragility of mould, adds toughness, and the distortion degree of steel is significantly less than low temperature quenching and produces Raw distortion；And the three sections of isothermal spheroidizings carried out subsequently eliminate net carbide and bulk tip-angled shape carbide further and eliminate Thick Structure Inheritance, after finished heat treatment, grain size refines, becomes round up to 10-12 level, carbide particle, make the impact toughness of steel Significantly improve, be greatly prolonged the mold use life-span；Last tempering makes the residualinternal stress produced during quenching be eliminated, And improve plasticity and the toughness of mould.And six sides forging method and use the mode of weight in forging medium temperature, on the one hand can keep away The strike exempting from forging makes carbide be smashed to smash, austenite gross distortion and produce processing hardening, on the other hand avoid because of hammer Hit too quickly, forging intensification make workpiece localized micro district rise to more than eutectic melting temperature, cause organizing overheated, burning, formed The problem of implosion.This mode Forging Technology combined with Technology for Heating Processing, can increase substantially the inherent matter of workpiece Amount, and reach energy-conservation, shorten the effect of production cycle.

Claims

1. the forging of Cr12MoV steel and Technology for Heating Processing, it is characterised in that: for the technique that material is Cr12MoV steel, including Following operation:

(3) oil or salt bath quenching are to 1100-1150 DEG C, are incubated 15min；

(4) cooling；

(6) 220 DEG C of tempering；

(7) come out of the stove, be placed in natural cooling in air.

The forging of Cr12MoV steel the most according to claim 1 and Technology for Heating Processing, it is characterised in that: to described Cr12MoV Steel uses hexahedro pier to pull out method, pulls out including three piers three, and total forging ratio is 15.

The forging of Cr12MoV steel the most according to claim 1 and Technology for Heating Processing, it is characterised in that: to described Cr12MoV Steel uses weight in the range of forging temperature 900 DEG C-1000 DEG C, uses light hammer during remaining forging.