Contact fatigue risk assessment method for carburized hardened gears considering residual stress

Abstract

The invention discloses a carburizing hardened gear contact fatigue risk assessment method with residual stress being considered. The method comprises the following steps: 1) establishing a two-dimensional contact mode through an ABAQUS platform; 2) testing distribution curve of residual stress and distribution curve of hardness of a gear sample; 3) according to the hardness curve of the gear sample and linear relation between the hardness and yield strength, obtaining a distribution curve of partial yield strength of the gear in the depth direction; 4) adding material attributes and an initial residual stress value to a finite element model through a Python programming language and combined with material local yield strength distribution curve and residual stress distribution curve; 5) through Dang Van multi-axis stress criterion, calculating equivalent stress of subsurface of the gear; and 6) calculating a fatigue failure risk value at any point in a key contact area. The technical effects are that, the method estimates contact fatigue risk of the carburizing hardened gear under the condition of considering the residual stress, thereby reducing loss of production benefits causedby contact fatigue failure of the hardened gear.

Description

technical field [0001] The invention belongs to a method for evaluating the risk of fatigue failure of mechanical parts, in particular to a method for evaluating the risk of contact fatigue failure of a surface-hardened gear pair represented by carburizing and quenching under the condition of considering residual stress. Background technique [0002] The surface hardening process typically represented by carburizing and quenching is widely used in heavy-duty gears such as wind power, ships, and high-speed rail. However, with the continuous improvement of mechanical equipment's requirements for gear transmission power density, surface hardened gears will still suffer from contact fatigue failure, which will affect the reliability of equipment. There are many factors affecting the fatigue failure risk of carburized hardened gears, such as the gradient of mechanical properties of materials, residual stress, and complex multi-axial stress state in the contact process, and in eng...

AI Technical Summary

Problems solved by technology

However, with the continuous improvement of mechanical equipment's requirements for gear transmission power density, surface hardened gears will still fail due to contact fatigue, which will affect the reliability of equipment.

There are many factors affecting the fatigue failure risk of carburized hardened gears, such as the gradient of mechanical properties of materials, residual stress, and complex multi-axial stress state in the contact process. there are great difficulties

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