Pressurized gas nitriding method on the surface of medium and low carbon alloy structural steel

A technology of low-carbon alloy and pressurized gas, which is applied in metal material coating process, coating, solid-state diffusion coating, etc., can solve the load-carrying and impact-resistant limitations of heavy-duty large-curvature-radius parts, and cannot replace deep carburizing , long time and other issues, to achieve the effect of enhancing the process effect, reducing the decomposition rate, and promoting the adsorption effect

Inactive Publication Date: 2015-09-16
YANSHAN UNIV
View PDF2 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The conventional gas nitriding process takes a long time, generally tens or even hundreds of hours, and the nitrided layer is relatively shallow, which limits the load-bearing and impact resistance of some heavy-duty and large-radius-of-curvature parts.
At present, conventional nitriding still cannot replace deep carburizing

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
  • Pressurized gas nitriding method on the surface of medium and low carbon alloy structural steel
  • Pressurized gas nitriding method on the surface of medium and low carbon alloy structural steel
  • Pressurized gas nitriding method on the surface of medium and low carbon alloy structural steel

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0014] Process 31CrMoV9 steel into a test piece and hang it in a solid solution nitriding furnace with the patent name "A pressurized high-temperature nitriding device with a double-pressure balance structure" and the patent number 201210530358.6. NH 3 The flow rate is 0.1L / min, the decomposition rate is 30-40%, and the nitriding treatment is carried out for 10 hours, and then NH is continuously fed 3 To the furnace, cooling to 100 ° C to end. Such as figure 1 As shown, the thickness of the infiltrated layer obtained by the test block is about 0.441mm.

Embodiment 2

[0016] Process 42CrMo steel into a test block and hang it in a solid solution nitriding furnace with the patent name "A pressurized high-temperature nitriding device with a double-pressure balance structure" and the patent number 201210530358.6. NH 3 The flow rate is 0.3L / min, the decomposition rate is 50-60%, nitriding treatment is carried out for 5 hours, and then NH is continuously fed 3 To the furnace, cooling to 100 ° C to end. Such as figure 2 As shown, the thickness of the infiltrated layer obtained by the specimen is 0.24mm.

Embodiment 3

[0018] The 20CrMnTi steel is processed into a test block and hung in the solid solution nitriding furnace with the patent name "A pressurized high-temperature nitriding device with a double-pressure balance structure" and the patent number is 201210530358.6. NH 3 The flow rate is 0.5L / min, the decomposition rate is 60% to 80%, the nitriding treatment is 20h, and then the NH is continuously fed 3 To the furnace, cooling to 100 ° C to end. Such as image 3 As shown, the thickness of the infiltrated layer obtained by the test block is about 0.692mm.

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 discloses a medium and low-carbon alloy constructional steel surface pressurization gas-nitridation method. The medium and low-carbon alloy constructional steel surface pressurization gas-nitridation method comprises the following steps of putting a medium and low-carbon alloy constructional steel workpiece into a solid solution nitrogenation furnace which is shown in the patent having a patent name of pressurization high-temperature nitridation device with dual pressure equilibrium structure and having the patent number of 201210530358.6, improving the pressure to 0.1-0.5MPa at a temperature of 500-800 DEG C, feeding NH3 into the solid solution nitrogenation furnace at a flow rate of 0.1-0.5L / min, carrying out gas nitridation treatment at a decomposition rate of 30-80% for 5-20 hours, sequentially feeding NH3 into the solid solution nitrogenation furnace, cooling to a temperature below 150 DEG C, and taking out the workpiece. The medium and low-carbon alloy constructional steel surface pressurization gas-nitridation method can effectively promote adsorption of N atoms on the part surface, improve N activity, an interface reaction rate and a hole and slit nitridation capability, reduce an NH3 decomposition rate, improve nitrogen potential, obviously reduce an NH3 consumption amount in nitridation, greatly improve process effects and realize short-term deep nitridation.

Description

technical field [0001] The invention belongs to the field of metal surface chemical heat treatment, and relates to a surface nitriding method of medium and low carbon alloy structural steel. Background technique [0002] Commonly used structural parts such as shafts and gears usually require nitriding treatment to improve their surface hardness, wear resistance and fatigue resistance. The conventional gas nitriding process takes a long time, generally tens or even hundreds of hours, and the nitrided layer is shallow, which limits the load-bearing and impact resistance of some heavy-duty and large-radius-of-curvature parts. At present, conventional nitriding still cannot replace deep carburizing. Contents of the invention [0003] The purpose of the present invention is to provide a pressurized gas nitriding method on the surface of medium and low carbon alloy structural steels which can realize short-term deep nitriding. The present invention mainly introduces pressure p...

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): C23C8/26
Inventor 傅万堂郭明伟王博曲明贵赵品郑炀曾吕知清
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