Low temperature carburization method of hot-working die steel

A technology of hot work die steel and low temperature carburizing, applied in the direction of coating, metal material coating process, solid diffusion coating, etc. Low, easy to operate, good wear resistance

Inactive Publication Date: 2012-05-23
SOUTH CHINA UNIV OF TECH
View PDF0 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, when the surface carbon exceeds 1.6wt.%, the martensite transformation temperature Ms point has dropped below 10°C, and martensite cannot be obtained by conventional quenching, and carburization strengthening loses its effect

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
  • Low temperature carburization method of hot-working die steel
  • Low temperature carburization method of hot-working die steel
  • Low temperature carburization method of hot-working die steel

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0035] Example 1 - Low temperature carburizing of hot work die steel HM1 → quenching and tempering → ion nitriding treatment

[0036] Hot work die steel HM1 is a new type of hot work die steel with good high temperature strength. HM1 composition grade is 3Cr 3 Mo 3 W 2 V, the steel contains four carbide-forming elements of Cr, Mo, W, and V. According to the mass content of the carbide-forming elements in HM1, the calculated molar content is about 8.6%. By consulting the material manual, it is known that the Ac1 temperature of HM1 is 850°C, and the supply state is spheroidized annealed structure (ferrite + granular carbide).

[0037] (1) First cut the sample into a size of Φ10×10mm, clean it with ultrasonic waves in 10wt.% NaOH solution for 20 minutes, then wash it with 8wt.% hydrochloric acid for 5 minutes, and finally dehydrate it with alcohol and place it in an oven below 120°C Dry and set aside.

[0038] (2) When the temperature of drip injection well type carburizing ...

Embodiment 2

[0044] Example 2 - Low-temperature carburizing of hot work die steel H13→quenching and tempering→soft nitriding treatment

[0045] Hot work die steel H13 is a widely used hot extrusion die for aluminum profiles, and its component grade is 4Cr 5 MoSiV1, the steel contains four carbide-forming elements of Cr, Mo, W, and V. According to the mass content of the carbide-forming elements of H13, the calculated molar content is about 7.2%. By consulting the material manual, it is known that the Ac1 temperature of H13 is 850°C, and the supply state is spheroidized annealed structure (ferrite + granular carbide).

[0046] (1) First cut the sample into a size of Φ10×10mm, clean it with ultrasonic waves in 10wt.% NaOH solution for 20 minutes, then wash it with 8wt.% hydrochloric acid for 5 minutes, and finally dehydrate it with alcohol and place it in an oven below 120°C Dry and set aside.

[0047] (2) When the temperature of the drop-injection well-type carburizing furnace reaches 650...

Embodiment 3

[0053] Embodiment 3 - Low temperature carburizing→quenching and tempering treatment of hot work die steel 3Cr2W8V

[0054] Hot work die steel 3Cr 2 W 8 V is the most widely used upsetting die and die-casting die steel for a long time. The steel contains three carbide-forming elements of Cr, W and V. According to the mass content of the carbide-forming elements of 3Cr2W8V, the calculated molar content is about 6%. . By consulting the material manual, it is known that the Ac1 temperature of 3Cr2W8V is 830°C, and the supply state is spheroidized annealed structure (ferrite + granular carbide).

[0055] (1) First cut the sample into a size of Φ10×10mm, clean it with ultrasonic waves in 10wt.% NaOH solution for 20 minutes, then wash it with 8wt.% hydrochloric acid for 5 minutes, and finally dehydrate it with alcohol and place it in an oven below 120°C Dry and set aside.

[0056] (2) When the temperature of the drop-injection well-type carburizing furnace reaches 650 °C, put the...

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
thicknessaaaaaaaaaa
hardnessaaaaaaaaaa
thicknessaaaaaaaaaa
Login to view more

Abstract

The invention discloses a low temperature carburization method of hot-working die steel. The implementation of the method requires that the content of carbide-forming element by weight percent in the hot-working die steel is 5 to 10 wt.% and carburization temperature is lower than austenization temperature Ac1. The preparation method comprises the following steps that: workpieces are subject to gas-exhausted heat-up, heat-preserved carburization and furnace-cooling temperature reduction in a drop feed carburizing furnace, and finally, the thickness and the uniformity of carburized layers are controlled by means of quenching and heat preservation, and the hardness and the toughness of carburized layers are controlled by annealing. The method can not only directly enhance the surface hardness of the quenched hot-working die steel to HRC60, but can also obtain the carburized layers having the thickness as high as 0.7 to 1.0mm so that the carburized layers can withstand heavy load and impact load high temperature friction and abrasion conditions. Nitriding and soft nitriding can be directly performed on the surface of the low temperature carburized layers, thereby further enhancing the surface hardness and simultaneously tremendously raising the ability of nitrided layers to withstand heavy load and impact load high temperature friction and abrasion.

Description

technical field [0001] The invention belongs to the field of metal surface chemical strengthening heat treatment, in particular to a low-temperature carburizing method for hot work die steel. Background technique [0002] Carburizing is currently the most widely used chemical heat treatment method in the machinery manufacturing industry. After quenching and tempering, the carburized layer has the advantages of thick carburized layer, high hardness, good toughness, and smooth transition from surface to matrix hardness. It can serve under heavy impact load and fatigue conditions. It is used in gears, cams and other fields. It is widely used and significantly improves the service life of the workpiece. [0003] The current carburizing technology is mostly used for carburizing steel with low carbon content. The alloy content is very low. After carburizing, the surface carbon concentration increases. After quenching + low temperature tempering (less than 250°C), the surface hard...

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 Patents(China)
IPC IPC(8): C23C8/22
Inventor 邱万奇孙歌钟喜春余红雅刘仲武曾德长
Owner SOUTH CHINA UNIV OF TECH
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

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap