Prediction method for crack initiation of secondary surface of heavy-load gear

Abstract

The invention discloses a prediction method for crack initiation of a secondary surface of a heavy-load gear. The method comprises the following steps that 1, based on a hertz contact theory, the contact of a gear pair is simplified, a meshed position parameter is calculated according to geometric kinematics, and a contact analysis model is established; 2, based on the contact analysis model of the gear pair, by using a value calculation method, the surface contact pressure of the analysis model under the heavy-load condition is obtained; 3, a material constant related to the service life of crack initiation is solved; 4, based on a continuous damage mechanics theory, by using critical damage amount, whether or not a crack occurs on the secondary surface is judged, and a gear contact elastic-plastic constitutive equation of coupling damage is established; 5, the service life of crack initiation is calculated, and the position of crack initiation is obtained. According to the predictionmethod, the technical difficult problem which exists for a long time in the machinery industry is solved, the position and service life of crack initiation of the secondary surface of the heavy-loadgear can be effectively predicted, and the basis is provided for design, manufacturing and use of the gear.

Description

technical field [0001] The invention relates to a method for assessing contact fatigue failure risk of mechanical parts, in particular to a method for predicting subsurface crack initiation of heavy-duty gears based on continuous damage mechanics. Background technique [0002] With the continuous development of modern industry, high speed, heavy load and high power density have become the symbols of continuous progress of large equipment. Such changes have higher requirements on the power density and service life of important components such as gears and bearings. However, under heavy load conditions, subsurface cracks will significantly affect the reliability and service life of mechanical equipment such as fans, helicopters, ships, etc., greatly affecting human-machine safety and economic benefits. Since the initiation of subsurface cracks will soon lead to gear failures such as broken teeth and spalling, but at the same time it is difficult to detect subsurface cracks du...

AI Technical Summary

Problems solved by technology

However, under heavy load conditions, subsurface cracks will significantly affect the reliability and service life of mechanical equipment such as fans, helicopters, ships, etc., greatly affecting human-machine safety and economic benefits

Since the initiation of subsurface cracks will soon lead to gear failures such as broken teeth and spalling, but at the same time it is difficult to detect subsurface cracks during gear operation, the evaluation and prediction of gear subsurface crack initiation is a technical problem in this field.

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