CN103276173B - Process method for rolling plate from 4Cr13 medium plate corrosion resistance mold steel - Google Patents

Abstract

The invention belongs to a process method for plate rolling, and particularly relates to a process method for rolling a plate from a 4Cr13 medium plate corrosion resistance mold steel, wherein treatments are performed according to the following steps: treating a blank material, rolling, carrying out air cooling to achieve a temperature of 200-250 DEG C, entering a low temperature tempering furnace (or a trolley furnace), discharging from the furnace and carrying out slow cooling, secondarily entering the low temperature tempering furnace, and carrying out slow cooling. The process method has the following beneficial effects that: problems of heat stress cracks and easy embrittlement during cooling after 4Cr13 medium plate rolling are solved, 4Cr13 medium plate mold steel plate rolling is achieved, a reasonable cooling manner is adopted to achieve pre-hardening of the 4Cr13 medium plate mold steel, the product successfully enters the market to be used, additional investment is not required, effects are good, and low cost and high profit production are achieved.

Description

A kind of processing method of 4Cr13 plate of moderate thickness anti-corrosion die steel rolled plate

Technical field

The invention belongs to the processing method of rolled plate, be specifically related to a kind of processing method of 4Cr13 plate of moderate thickness anti-corrosion die steel rolled plate.

Background technology

4Cr13 is high-grade Corrosion Resistant Stainless Steel for Plastic Mould, belong to martensite type stainless steel, this steel machining property is better, after heat treatment have excellent corrosion resistance nature, polishing performance, higher intensity and wear resistance, high loading, high abrasion and the mould of plastics under corrosive medium effect and transparent plastics die products mould etc. are born in suitable manufacture.But 4Cr13 is air-cooled martensitic steel, the rolling type of cooling is improper easily to be burst; Quenching crack susceptibility is strong, needs timely annealing after rolling.At present, this steel grade is domestic does not have rolled plate, only has forging material (bar steel).

Summary of the invention

Technical problem to be solved by this invention is: how to solve crack due to thermal stress or the easy embrittlement problem of sheet material after 4Cr13 rolling.

The technical solution adopted in the present invention is: a kind of processing method of 4Cr13 plate of moderate thickness anti-corrosion die steel rolled plate, carries out as follows

Step one, 4Cr13 plate of moderate thickness anti-corrosion die steel blank is put into process furnace and heats, preheating section temperature≤900 DEG C, heating zone and soaking zone temperature are 1220-1240 DEG C, and rate of heating is according to 0.9min/mm-1min/mm; Rate of heating is determined according to the thickness of sheet material, and min/mm to refer to minute/mm of thickness.

Step 2, roll cooling water is flow minimally, quick roll forming, and during de-scaling, high pressure water flushing is once; For avoiding steel plate rolling crackle, keep high temperature rolling, during de-scaling, high pressure water once.

Step 3, after rolling, stacking on low-temp temper furnace or car type furnace chassis, buttress layer is 5-6 layer, and air cooling is to 200-250 DEG C;

Step 4, in low-temp temper furnace, heats up by 25 DEG C/h, and when furnace temperature rises to 300 DEG C, constant temperature is lowered the temperature after keeping 6 hours, cooling rate 25-30 DEG C/h, after dropping to 200 DEG C, and furnace cooling;

Step 5, after cold charge, heats up by 25 DEG C/h in low-temp temper furnace, rise to 300 DEG C of insulation 4h, continue to rise to 400 DEG C of insulation 4h, continue to be warming up to 500 DEG C of insulation 4h, continue to be warming up to 550 DEG C of insulation 6 h, continue to be warming up to 600 DEG C of insulation 1000min, air cooling is down to 200 DEG C and is come out of the stove.

The invention has the beneficial effects as follows: solve the problem that 4Cr13 plate of moderate thickness rolls rear crack due to thermal stress, cools easy embrittlement.Achieve 4Cr13 plate of moderate thickness die steel plate rolling.Adopt the rational type of cooling, achieve 4Cr13 plate of moderate thickness die steel and firmly produce in advance.This product is made successfully to come into the market to use.Do not need extra input, effective, achieve low cost, high profit is produced.

Embodiment

The technical process of the present embodiment is as follows:

heating and temperature control: preheating section temperature controls 500 DEG C in process furnace, heating zone and soaking zone control temperature are 1230 DEG C, and rate of heating controls according to 9-10min/10mm.

Roll cooling water turns down, and require two rollers, four rollers rob temperature and roll soon, de-scaling high pressure water flushing once, avoids steel plate rolling crackle.

After rolling, steel plate air cooling places 230 DEG C, is directly adjusted to stacking on low-temp temper furnace or car type furnace chassis, and every 5-6 opens a buttress (stacking), and between buttress and buttress, available parallels separates, and font that parallels is put into " ", is conducive to radiation and transmission of heat by convection like this.

When steel plate is cooled to 200 DEG C, carry out go-cart shove charge, close fire door and carry out stress annealing.

Annealing temperature: heat up by 25 DEG C/h, when furnace temperature rises to 300 DEG C, carries out thermostatic control after 6 hours, lowers the temperature, cooling rate 25 DEG C/h, after dropping to 200 DEG C, and furnace cooling.

Carry out secondary to cooled 4Cr13 to enter low-temp temper furnace and carry out pre-hard process:

After steel plate cold charge, heat up by 25 DEG C/h, rise to 300 DEG C of insulation 4h, continue to rise to 400 DEG C of insulation 4h, continue to be warming up to 500 DEG C of insulation 4h, continue to be warming up to 550 DEG C of insulation 6 h, continue to be warming up to 600 DEG C of insulation 1000min, air cooling is down to 200 DEG C and is come out of the stove.

Claims (1)

1. a processing method for 4Cr13 plate of moderate thickness anti-corrosion die steel rolled plate, is characterized in that: carry out as follows

Step one, 4Cr13 plate of moderate thickness anti-corrosion die steel blank is put into process furnace and heats, preheating section temperature≤900 DEG C, heating zone and soaking zone temperature are 1220-1240 DEG C, and rate of heating is according to 0.9min/mm-1min/mm;

Step 2, roll cooling water is flow minimally, quick roll forming, and during de-scaling, high pressure water flushing is once;

Step 3, after rolling, stacking on low-temp temper furnace or car type furnace chassis, buttress layer is 5-6 layer, and air cooling is to 200-250 DEG C;

Step 4, in low-temp temper furnace, heats up by 25 DEG C/h, and when furnace temperature rises to 300 DEG C, constant temperature is lowered the temperature after keeping 6 hours, cooling rate 25-30 DEG C/h, after dropping to 200 DEG C, and furnace cooling;

Step 5, after cold charge, heats up by 25 DEG C/h in low-temp temper furnace, rise to 300 DEG C of insulation 4h, continue to rise to 400 DEG C of insulation 4h, continue to be warming up to 500 DEG C of insulation 4h, continue to be warming up to 550 DEG C of insulation 6 h, continue to be warming up to 600 DEG C of insulation 1000min, air cooling is down to 200 DEG C and is come out of the stove.