I try to calculate the stresses resulted on gear teeth, first with using normal steel and then using powder metal properties (as shown in the properties below). I kept the same geometry and the same torque levels applied, but I got lower stresses with powder metal.! I expected to get similar stress results as the load and geometry are kept the same, where basically the stress= load/area. Do you have some useful comment about this?
For steel gear, I input E=207 Gpa, v=0.3
For PM gears, I input E=154 Gpa, v=0.28 (approximately)
Dear sir
It is true that stresses are independent of the material properties but only within the linear elastic conditions.
If you are performing FE analysis then the Young modulus, Poisson ratio and Shear modulus will be used to form a global stiffness matrix. Therefore the material properties of gear affects the stresses developed in your model.
In addition to Mr. Saxena answer about non-linearity in the stress-strain relation. Also, if the load is large enough to produce large deflection, the strain-displacement relations contains nonlinear terms too. And if you measure the stress through the strain gauge, the material properties affect on stress of the body.
Thank you for your answer and sharing information.
I was thinking about that for several days. The analysis is still within Elastic range, but I think as the material gets softer the load distribution on the tooth flank is changed and it can has some impact on root bending stress. On the other hand, the contact stress is depending on the modulus of Elasticity. Do you think this can explain the problem?
Because the module of elasticity change and consequently the deformation, strains and stresses of the teeth.
- Badges
- Science topic
- Similar topics
- Engineering
- Materials Engineering
- Powders