Method for improving mechanical properties of surface of non austenitic stainless steel

A mechanical property, stainless steel technology, applied in the direction of metal material coating process, coating, solid diffusion coating, etc., can solve the problem of limited improvement of surface mechanical properties, achieve excellent corrosion resistance, improve mechanical properties, and improve surface mechanical properties effect of nature

Active Publication Date: 2012-09-19
SUZHOU ZHONGYAO TECH CO LTD
View PDF15 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0007] The main purpose of the present invention is to solve the problem of limited improvement of the surface mechanical properties of the known methods for improving the mechanical properties of non-austenitic stainless steel

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
  • Method for improving mechanical properties of surface of non austenitic stainless steel
  • Method for improving mechanical properties of surface of non austenitic stainless steel
  • Method for improving mechanical properties of surface of non austenitic stainless steel

Examples

Experimental program
Comparison scheme
Effect test

experiment example 1

[0050] In this experimental example, a stainless steel workpiece of composition 1 was first put into an atmosphere sintering furnace and passed through cracked ammonia, and kept at a process temperature of 1320°C for 2 hours to form a nitrogen-rich layer with a thickness of about 50 μm on the surface of the stainless steel workpiece. Then, the stainless steel workpiece is taken out from the atmosphere sintering furnace, and placed in a carburizing furnace, and carbon monoxide gas is passed through the furnace, and the temperature in the furnace is lowered to 500 ° C, and the temperature is maintained for 24 hours. The surface of the stainless steel workpiece A carburized layer with a thickness of about 21 μm can be formed, the surface hardness is about HV 650, and the core hardness is about HV 370. The corrosion resistance is qualified and can withstand 40 hours in the salt spray test.

experiment example 2

[0052] In this experimental example, a stainless steel workpiece of composition 1 was first put into an atmosphere sintering furnace and passed through cracking ammonia, and kept at a process temperature of 1120°C for 2 hours to form a nitrogen-rich layer with a thickness of about 35 μm on the surface of the stainless steel workpiece. Then, the stainless steel workpiece is taken out from the atmosphere sintering furnace, placed in a carburizing furnace, and carbon monoxide gas is passed through the furnace, and the temperature in the furnace is lowered to 500 ° C, and the temperature is maintained for 24 hours. The stainless steel workpiece A carburized layer with a thickness of about 20 μm can be formed on the surface. The surface hardness is about HV 653, and the core hardness is about HV 365. The corrosion resistance is qualified and can withstand 40 hours in the salt spray test.

experiment example 3

[0054] In this experimental example, a stainless steel workpiece with composition 1 is used. A nickel layer with a thickness of about 0.5 μm is first plated on the surface of the stainless steel workpiece, and then a homogenization step is performed. The stainless steel material is put into an atmosphere sintering furnace, and cracked ammonia is passed through it and Raise the temperature to 1320°C, hold the temperature for 2 hours, then lower the atmosphere sintering furnace to room temperature, then put the stainless steel material into the carburizing furnace, pass through carbon monoxide gas and raise the temperature of the carburizing furnace to 500°C, and hold the temperature for 24 hours A carburized layer with a thickness of about 25 μm can be formed on the surface of the stainless steel workpiece. The surface hardness is about HV 710, and the core hardness is about HV 350. The corrosion resistance is qualified and can withstand 42 hours in the salt spray test.

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
thicknessaaaaaaaaaa
thicknessaaaaaaaaaa
Login to view more

Abstract

The invention provides a method for improving mechanical properties of the surface of non austenitic stainless steel. The method comprises the following steps: putting a non austenitic stainless steel material into an environment comprising at least one austenitic stabilizing element, and making the austenitic stabilizing element disperse to the surface of the stainless steel material to form a modified layer, wherein the modified layer is rich in the austenitic stabilizing element; and putting the stainless steel material into a carbon-containing atmosphere, making the modified layer contact the carbon-containing atmosphere, keeping carburizing temperature of lower than 600DEG C, and making carbon enter the modified layer to form a carburized layer. By the carburized layer, the mechanical properties of the surface of the non austenitic stainless steel material can be improved, and the non austenitic stainless steel material can be applied to appearance products and structural parts, which require high wear resistance, high surface hardness and high corrosion resistance.

Description

technical field [0001] The invention relates to a method for improving the surface mechanical properties of non-austenitic stainless steel, especially a method for carburizing non-austenitic stainless steel at low temperature to improve the surface mechanical properties. Background technique [0002] Stainless steel can be mainly divided into Austenite stainless steel, Martensite stainless steel and Ferrite stainless steel according to its structure. It is suitable as a structure due to its excellent anti-corrosion properties Parts or appearance parts that require decorative effects, such as screws, nuts, pivots, bolts and other workpieces; or such as watches, mobile phones and other electronic products, accessories, housings of household appliances, etc. However, the surface mechanical properties of general stainless steel cannot meet the needs of practical applications. For example, the common American iron and steel institute (AISI) 316L stainless steel contains 15 to 18%...

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): C23C8/20C23C8/02
Inventor 黄坤祥郑礼辉陆永忠范扬梁陈柏翰
Owner SUZHOU ZHONGYAO TECH CO LTD
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