Nitrided parts and nitrocarburized parts excellent in wear resistance and pitting resistance, nitriding method, and nitrocarburized method

Abstract

Provide nitriding and nitrocarburized parts with excellent wear resistance and pitting resistance, nitriding methods, and nitrocarburizing methods. A nitriding treatment part or soft nitriding treatment part, characterized in that it is made of steel, and the steel contains C: 0.05-0.3%, Si: 0.05-1.5%, Mn: 0.2% by mass % ~1.5%, P: 0.025% or less, S: 0.003~0.05%, Cr: 0.5~2.0%, Al: 0.01~0.05% and N: 0.003~0.025%, the balance contains Fe and impurities, and the surface layer contains iron, A compound layer of nitrogen and carbon and a nitrogen diffusion layer below it, the compound layer is composed of an ε single phase, the thickness of the ε single phase is 8-30 μm, and the Vickers hardness is above 680 HV, and the ε single phase The volume ratio of the pores is less than 10%.

Description

technical field [0001] The present invention relates to parts produced by gas nitriding and gas soft nitriding, especially parts such as CVT pulleys and gears that require wear resistance and pitting resistance, and gas nitriding used in the manufacture of these parts , Gas nitrocarburizing treatment method. Background technique [0002] Among steel parts used in automobiles, various industrial machines, etc., some parts require surface fatigue strength. For example, CVT pulleys in transmissions require wear resistance, and gears require fatigue characteristics such as pitting resistance. In order to improve these characteristics, it is considered more effective to increase the surface hardness, and the application of nitriding and nitrocarburizing treatments has been continuously developed. Nitriding treatment and nitrocarburizing treatment have the advantages that high surface hardness can be obtained and heat treatment deformation is small. [0003] Nitriding treatment...

AI Technical Summary

Problems solved by technology

In Patent Document 1, there is a description about the nitrogen content on the steel surface, but there is no description about the components, composition, and properties of the compound layer formed in the nitriding treatment.

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