Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Electric pulse-assisted nitriding method of austenitic stainless steel

An austenitic stainless steel, electric pulse technology, applied in the direction of metal material coating process, coating, solid diffusion coating, etc., can solve the problems of pollution, narrowing of application scope, difficult to treat waste water, etc.

Inactive Publication Date: 2014-04-23
LIAONING UNIVERSITY OF TECHNOLOGY
View PDF3 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] Compared with other nitriding processes, the production efficiency of gas nitriding has been significantly improved, and the depth of nitrogen nitriding can reach between 100-200 μm, which is suitable for large-scale mass production, but there are many problems, that is, the pollution problem is very serious and the cost of tail gas treatment is very high. High energy consumption, high energy consumption due to slow permeation rate, high consumption of ammonia gas, waste gas and waste water are difficult to treat, and its application range is gradually shrinking

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
  • Electric pulse-assisted nitriding method of austenitic stainless steel
  • Electric pulse-assisted nitriding method of austenitic stainless steel
  • Electric pulse-assisted nitriding method of austenitic stainless steel

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0020] The nitriding method of austenitic stainless steel will be described in detail below. This embodiment takes 1Cr18Ni9Ti as an example for demonstration, and this exemplary embodiment does not limit the scope of protection of the claims.

[0021] First, the 1Cr18Ni9Ti workpiece that needs to be infiltrated with N is treated, and the surface of the workpiece is sandblasted or pickled to remove the passivation film on the surface of 1Cr18Ni9Ti that hinders the diffusion of N.

[0022] Configure nitrogenizing agent, which is a mixture of wood chips, urea, sodium carbonate and ammonium chloride, and mix evenly according to the mass ratio of 10:6:3:1. After calculation and many experiments, the nitriding agent according to this mass ratio can achieve the best required technical effect. Among them, urea is the source of the main active N element, sawdust can improve the activity of the penetrating agent, ammonium chloride is heated and decomposed to produce HCl gas, which can c...

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

An electric pulse-assisted nitriding method of austenitic stainless steel comprises the following steps: preparing a nitriding medium, uniformly mixing wood chips, urea, sodium carbonate and ammonium chloride according to a mass ratio of 10:6:3:1; turning on a heat treatment furnace power supply to increase the temperature in the furnace to 500-700 DEG C, performing heat preservation for 1 hour, then performing electric pulse treatment for 10 minutes with pulse parameters of 6.5-9 KV of voltage and 7-10 Hz of frequency, stopping electric pulse, waiting for 50 minutes, then performing electric pulse treatment for 10 minutes with the same parameters, and repeating the above treatment for more than four times. The method of the invention improves the nitriding efficiency, shortens the nitriding time, and greatly reduces the energy consumption.

Description

technical field [0001] The invention relates to a nitriding method, in particular to an electric pulse assisted nitriding method for austenitic stainless steel. Background technique [0002] Austenitic stainless steel refers to those stainless steels whose microstructure is austenitic in use. The main chemical components of austenitic stainless steel are Cr, Ni, Mn, N and other elements. Cr ≥ 18% and Ni ≥ 8% in austenitic stainless steel, and the combination of Cr 18% and 8% Ni is a typical composition of austenitic stainless steel in various countries in the world. Austenitic stainless steel is currently the most widely used stainless steel in the world, accounting for nearly 2 / 3 of the world's total stainless steel production. At the same time, because austenitic stainless steel has excellent acid resistance, oxidation resistance, radiation resistance, high temperature and low temperature mechanical properties, biocompatibility, etc., it is widely used in petroleum, ...

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): C23C8/62
Inventor 刘兴江齐锦刚王建中孙玉玲吴敌李扬
Owner LIAONING UNIVERSITY OF TECHNOLOGY
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com