Efficient pre-hardening method for steel and steel workpiece

A high-efficiency, workpiece-friendly technology, applied in the direction of manufacturing tools, furnace types, furnaces, etc., can solve the problems of steel workpiece damage, inability to deal with surface shape steel workpieces, etc.

Active Publication Date: 2021-12-31
YANSHAN UNIV
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the existing pre-hardening processes, such as explosive hardening, mechanical impact hardening, etc., are very easy to cause damage to steel workpieces, and cannot handle steel workpieces with complex surface shapes, such as steel with curved surfaces and inner holes. workpiece

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
  • Efficient pre-hardening method for steel and steel workpiece
  • Efficient pre-hardening method for steel and steel workpiece
  • Efficient pre-hardening method for steel and steel workpiece

Examples

Experimental program
Comparison scheme
Effect test

example 1

[0093] In this example, the steel workpiece to be treated is made of ordinary high manganese austenitic steel material, the main chemical composition (wt.%) is C: 1.05, Si: 0.30, Mn: 13.05, and the rest is iron and other impurities. First, the steel workpiece to be treated is subjected to conventional water toughening process: after heating to 1050°C, water cooling to room temperature. At this time, the hardness of the high manganese steel is 220HV, the tensile strength of the matrix is ​​820MPa, and the elongation is 42%. Next, using induction heat treatment, the surface of the steel workpiece to be treated was heated to 500°C at a heating rate of 35°C / s, kept for 3s, and then water-cooled to room temperature with an average cooling rate of 80°C / s. After that, a heating and cooling process is performed in a cycle: the steel workpiece to be processed is heated until the surface temperature reaches 500°C, kept for 1s, and then cooled to room temperature with water, with an aver...

example 2

[0096] In this example, the steel workpiece to be treated is made of ordinary high manganese austenitic steel material, the main chemical composition (wt.%) is C: 1.05, Si: 0.30, Mn: 13.05, and the rest is iron and other impurities. First, the steel workpiece to be treated is subjected to conventional water toughening process: heating to 1050°C, cooling to room temperature by water cooling. At this time, the hardness of the high manganese steel is 220HV, the tensile strength of the matrix is ​​820MPa, and the elongation is 42%. Using direct current heating, the surface of the steel workpiece to be treated is heated to 700°C at a heating rate of 80°C / s, kept for 3s, and then cooled to room temperature by blowing helium, with an average cooling rate of 50°C / s. Afterwards, a heating and cooling process is performed in a cycle: the steel workpiece to be processed is heated until the surface temperature reaches 550°C, kept for 1s, and then water-cooled to room temperature, with an ...

example 3

[0099] In this example, the steel workpiece to be treated is made of alloyed high manganese austenitic steel material, the main chemical composition (wt.%) is C: 1.15, Si: 0.44, Mn: 11.8%, Cr: 0.6, and the rest is iron and other impurities. First, the steel workpiece to be treated is subjected to conventional water toughening process, heated to 1080°C, and cooled to room temperature by water cooling. At this time, the hardness of the high manganese steel is 240HV, the tensile strength of the matrix is ​​855MPa, and the elongation is 38%. Next, the flame heating method was used to heat the surface of the steel workpiece to be treated to 450°C at a heating rate of 110°C / s and keep it warm for 10s. After that, it was cooled to room temperature in ice water with an average cooling rate of 130°C / s. After the above process, refer to Figure 5 The microhardness curve of the steel workpiece to be processed is shown. The surface hardness of the steel workpiece to be processed is 290H...

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

PropertyMeasurementUnit
hardnessaaaaaaaaaa
hardnessaaaaaaaaaa
tensile strengthaaaaaaaaaa
Login to view more

Abstract

The invention provides an efficient pre-hardening method for steel and a steel workpiece. The method comprises the steps that the to-be-treated steel workpiece is obtained; first-stage heat treatment is conducted on the to-be-treated steel workpiece, and the to-be-treated steel workpiece is heated to a first hardening temperature so as to enable the to-be-treated steel workpiece to generate strain hardening based on an expansion strain gradient; and second-stage heat treatment is conducted on the to-be-treated steel workpiece at the first hardening temperature, and the to-be-treated steel workpiece is rapidly cooled to the second hardening temperature, so that the to-be-treated steel workpiece generates strain hardening based on the shrinkage strain gradient. Pre-hardening of the steel workpiece is achieved in a heat treatment mode, so that pre-hardening treatment can be efficiently conducted on steel workpieces of different shapes.

Description

technical field [0001] The invention relates to the technical field of steel workpiece preparation, in particular to a high-efficiency pre-hardening method for steel. Background technique [0002] During the preparation process of existing steel workpieces, steel workpieces with lower initial hardness (such as high manganese austenitic steel workpieces) are usually pre-hardened to increase the initial hardness of the steel workpieces. However, the existing pre-hardening processes, such as explosive hardening, mechanical impact hardening, etc., are very easy to cause damage to steel workpieces, and cannot handle steel workpieces with complex surface shapes, such as steel with curved surfaces and inner holes. artifact. [0003] Therefore, there is an urgent need for a pre-hardening method that can effectively reduce damage to steel workpieces while increasing the initial hardness of steel workpieces, and can adapt to steel workpieces with different surface shapes. Contents ...

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
Patent Type & Authority Applications(China)
IPC IPC(8): C21D1/06C21D1/78C21D6/00C21D9/00C22C38/02C22C38/04C22C38/38C21D1/08
CPCC21D1/06C21D1/78C21D6/005C21D9/0068C21D6/008C22C38/02C22C38/04C22C38/38C21D6/002C21D1/08
Inventor 杨志南张福成闫学峰房启文陈晨王建军李艳国王明明
Owner YANSHAN UNIV
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