Quenching process of H13 steel for compression molds

A die-casting mold and process technology, applied in the field of quenching technology, can solve the problems of affecting the service life of the mold, reducing the comprehensive performance of the workpiece, and low cooling speed, so as to reduce the probability of occurrence, ensure the quality of quenching, and control the amount of deformation.

Active Publication Date: 2010-09-01
GUANGZHOU DIE & MOLD MFG
View PDF3 Cites 18 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, this quenching process also has a huge disadvantage, which is manifested in the low cooling rate of the workpiece at low temperature (below about 550°C) during the quenching cooling stage, which means that the cooling rate of the workpiece in the bainite transformation zone is low, and the quenching process is prone to die casting The bainite that is not expected to appear in the mold, if the upper bainite appears, it will seriously affect the service life of the mold, and at the same time, due to the low cooling rate, the workpiece will retain a certain amount of residual austenite, resulting in a decrease in the overall performance of the workpiece
And the thicker the effective thickness of the workpiece, the worse its internal structure and the worse its comprehensive performance

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Quenching process of H13 steel for compression molds
  • Quenching process of H13 steel for compression molds
  • Quenching process of H13 steel for compression molds

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0029] Vacuum the vacuum high-pressure gas quenching furnace until the pressure in the furnace is 0.8X10 -1 Pa, after filling high-purity N with a pressure of 100Pa 2 Protect; heat up at a heating rate of 5°C / min, and keep warm when the furnace temperature reaches 600°C until the temperature difference between the surface of the treated piece and the core is less than 50°C; continue heating at a heating rate of 5°C / min, when the furnace When the temperature reaches 800°C, heat preservation is carried out until the temperature difference between the surface of the treatment piece and the core is less than 50°C; then continue to heat up at a heating rate of 10°C / min. When the furnace temperature reaches 980°C, heat preservation is carried out until the treatment piece is completely heated. Continue to keep warm for 30 minutes. Fill the vacuum high-pressure gas quenching furnace with N2, and cool the treated piece to a core temperature of 590°C; then take the resulting treated p...

Embodiment 2

[0031] Vacuum the vacuum high-pressure gas quenching furnace until the pressure in the furnace is 1.0X10 -1 Pa, after filling high-purity N with a pressure of 1000Pa 2 Protect; heat up at a heating rate of 8°C / min, and keep warm when the furnace temperature reaches 650°C until the temperature difference between the surface of the treated piece and the core is less than 50°C; continue heating at a heating rate of 8°C / min, when the furnace When the temperature reaches 850°C, heat preservation is carried out until the temperature difference between the surface of the treatment piece and the core is less than 50°C; then continue to heat up at a heating rate of 8°C / min. When the furnace temperature reaches 1050°C, heat preservation is carried out until the treatment piece is completely heated. Continue to keep warm for 15 minutes. Fill N into the vacuum high-pressure gas quenching furnace 2 , cooling the treated piece to a core temperature of 620°C, and keeping it warm in a vacuu...

Embodiment 3

[0033] Vacuum the vacuum high-pressure gas quenching furnace until the pressure in the furnace is 0.9X10 -1 Pa, after filling with high-purity N with a pressure of 10Pa 2 Protect; heat up at a heating rate of 6°C / min, and keep warm when the furnace temperature reaches 625°C until the temperature difference between the surface of the treated piece and the core is less than 50°C; continue heating at a heating rate of 6°C / min, when the furnace When the temperature reaches 840°C, heat preservation is carried out until the temperature difference between the surface of the treatment piece and the core is less than 50°C; then continue to heat up at a heating rate of 9°C / min. When the furnace temperature reaches 1000°C, heat preservation is carried out until the treatment piece is completely heated. Continue to keep warm for 20 minutes. Fill N into the vacuum high-pressure gas quenching furnace 2 , cool the treated piece to a core temperature of 600°C, then take the treated piece ou...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a quenching process of H13 steel for compression molds. The process comprises the following steps: multi-stage heating, N2 cooling and oil cooling. The invention changes the quenching cooling medium of a processed element while the steady temperature zone of the material quenched structure changes, i.e. the processed element is transferred from a vacuum high-pressure air quenching furnace to a quenching oil furnace to be cooled. The characteristic of high cooling speed of the quenching oil furnace can be utilized, so that the cooling curve quickly bypasses the bainite structure transition zone and enters the martensitic structure transition zone; and thus, the microstructure of the processed element can be transformed into martensite as much as possible so as to reduce or avoid carbides, bainite and residual austenite precipitating along the grain boundary, thereby enhancing the comprehensive mechanical properties of the processed element and enhancing the operation reliability of the mold. The invention is especially suitable for quenching large and complicated workpieces, and can ensures the quenching quality of the workpieces on the premise of no cracking.

Description

technical field [0001] The invention relates to a heat treatment process for H13 steel, in particular to a quenching process for this type of steel. Background technique [0002] At present, the die-casting mold usually uses H13 steel, and its quenching process adopts the process of vacuum high-pressure gas quenching. The workpiece treated by this process has the characteristics of no oxidation and decarburization on the surface and small deformation of the workpiece, which can basically avoid quenching cracking, so Widely used in the industry. However, this quenching process also has a huge disadvantage, which is manifested in the low cooling rate of the workpiece at low temperature (below about 550°C) during the quenching cooling stage, which means that the cooling rate of the workpiece in the bainite transformation zone is low, and the quenching process is prone to die casting The bainite that is not expected to appear in the mold will seriously affect the service life o...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): C21D1/19
Inventor 马广兴刘桂平
Owner GUANGZHOU DIE & MOLD MFG
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products