Checking calculations of stresses in gears using ANSYS

Active surfaces of most gears are hardened, cemented, or azotized. Therefore, the stressstrain analysis of gear teeth at various stages of action is of great importance. The areas where stresses can attain maximum permissible values can be evaluated using the ANSYS software package. A surface hardened tooth is a bimetallic structure whose surface and core consist of materials with different physical and mechanical properties. Any surface hardening causes changes in the stress-strain state due to the residual stresses that must be taken into account along with the stresses caused by external loads. This approach is based on the corresponding physical model and calculation technique. Classical methods used for calculating the properties of hardened gears do not take into account specific structure and properties of the hardened layer and core. The importance and role of residual stresses in determining permissible stresses, as well as their dependence on the structure and properties of carburized steel, are studied. Shear stresses are computed to evaluate contact strength. Due to the numerical methods applied in ANSYS, the difference between the calculated bending and contact strength is negligible, which makes it possible to use standard mechanical properties rather than empirical coefficients.

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