Unlock instant, AI-driven research and patent intelligence for your innovation.

A large deformation enhanced rapid ion nitriding method

A technology of ion nitriding and large deformation, which is applied in the direction of solid-state diffusion coating, coating, metal material coating process, etc., can solve the problems of core strength decline, surface layer peeling, large hardness gradient, etc., and achieve strength and hardness Improve and overcome the hardness drop and deformation of the core, and reduce the effect of nitriding temperature

Active Publication Date: 2020-08-14
CHANGZHOU UNIV
View PDF8 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] The technical problem to be solved by the present invention is: when the austenitic stainless steel is treated with ion nitriding, the high-temperature heating adopted to accelerate the diffusion will bring negative effects such as core strength reduction and deformation, and there are also shallow nitriding layers, Low hardness and large hardness gradient lead to problems such as relaxation of residual compressive stress and peeling of the surface layer on the surface layer. The present invention provides a large deformation enhanced rapid ion nitriding method

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
  • A large deformation enhanced rapid ion nitriding method
  • A large deformation enhanced rapid ion nitriding method
  • A large deformation enhanced rapid ion nitriding method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0031] (1) Processing the original state steel into a plate shape;

[0032] (2) Perform solid solution treatment on the plate-shaped steel to be nitrided, raise the temperature to 1050°C and keep it warm for 60 minutes, and then immediately put the sample into water to cool to room temperature;

[0033] (3) Place the solid solution state steel to be nitrided on the four-roll experimental rolling mill, and carry out cold rolling treatment with a deformation of 30%, resulting in large plastic deformation;

[0034] (4) The steel to be nitrided after large plastic deformation is processed by wire cutting into a sample size of 10mm×10mm×5mm. Ultrasonic cleaning in organic solvents and drying after grinding;

[0035] (5) Place the sample in the ion nitriding furnace, evacuate to below 10Pa, pass in hydrogen gas for sputtering for 30min, and keep the pressure in the furnace at 300Pa. Then nitrogen gas was introduced, the flow rates of nitrogen gas and hydrogen gas were 200ml / min an...

Embodiment 2

[0039] (1) Processing the original state steel into a plate shape;

[0040] (2) Perform solid solution treatment on the plate-shaped steel to be nitrided, raise the temperature to 1050°C and keep it warm for 60 minutes, and then immediately put the sample into water to cool to room temperature;

[0041] (3) Place the solid solution state steel to be nitrided on the four-roll experimental rolling mill, and carry out cold rolling treatment with a deformation of 50%, resulting in large plastic deformation;

[0042] (4) The steel to be nitrided after large plastic deformation is processed by wire cutting into a sample size of 10mm×10mm×5mm. Ultrasonic cleaning in organic solvents and drying after grinding;

[0043] (5) Place the sample in the ion nitriding furnace, evacuate to below 10Pa, pass in hydrogen gas for sputtering for 30min, and keep the pressure in the furnace at 300Pa. Then nitrogen gas was introduced, the flow rates of nitrogen gas and hydrogen gas were 200ml / min an...

Embodiment 3

[0047] (1) Processing the original state steel into a plate shape;

[0048] (2) Perform solid solution treatment on the plate-shaped steel to be nitrided, raise the temperature to 1050°C and keep it warm for 60 minutes, and then immediately put the sample into water to cool to room temperature;

[0049] (3) Place the solid solution state steel to be nitrided on the four-roll experimental rolling mill, and carry out cold rolling treatment with a deformation of 70%, resulting in large plastic deformation;

[0050] (4) The steel to be nitrided after large plastic deformation is processed by wire cutting into a sample size of 10mm×10mm×5mm. Ultrasonic cleaning in organic solvents and drying after grinding;

[0051](5) Place the sample in the ion nitriding furnace, evacuate to below 10Pa, pass in hydrogen gas for sputtering for 30min, and keep the pressure in the furnace at 300Pa. Then nitrogen gas was introduced, the flow rates of nitrogen gas and hydrogen gas were 200ml / min and...

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 belongs to the technical field of metal surface treatment, and relates to a large-deformation enhanced rapid ion nitriding method. The large-deformation enhanced rapid ion nitriding method comprises the specific steps that original steel is machined and cut into a plate shape; plate-shaped to-be-nitrided steel is subjected to solution treatment; solid-solution-state to-be-nitrided steel is placed in a cold rolling machine to be subjected to cold rolling treatment; and the large-plastic-deformation to-be-nitrided steel obtained after cold rolling treatment is machined and cut intoa sample, and then ion nitriding treatment is conducted. According to the method, the large plastic deformation treatment is conducted before ion nitriding, the dislocation density in a microstructure is obviously increased, grains are obviously refined, in the nitriding process, a rapid diffusion channel is provided for nitrogen atoms through high-density dislocation and other defects, the ion nitriding efficiency is obviously improved, and the thickness of a nitriding layer is improved; and under the situation that the same nitriding layer depth is obtained, the nitriding time can be greatly shortened, accordingly, the energy is saved, and the production cost is reduced.

Description

technical field [0001] The invention belongs to the technical field of metal surface treatment, in particular to a large deformation enhanced rapid ion nitriding method. Background technique [0002] Austenitic stainless steel has good corrosion resistance, oxidation resistance and high temperature resistance, and is widely used in aviation, aerospace, transportation, chemical and other fields. However, due to its low hardness and poor wear resistance, it often fails prematurely due to surface wear under normal service conditions, which limits its popularization and application. [0003] Ion nitriding technology has been widely used due to the advantages of uniform nitriding layer, simple process, good repeatability and no pollution. Austenitic stainless steel has excellent wear resistance, fatigue resistance and high temperature resistance after nitriding treatment. There are problems such as shallow nitriding layer, low hardness and large hardness gradient, which lead to...

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): C23C8/38C21D8/02
CPCC21D8/0205C21D8/0236C21D8/0247C21D8/0278C23C8/38
Inventor 胡静李冬魏伟魏坤霞
Owner CHANGZHOU UNIV