Surface treatment shopeened and cold worked why?

Pablo Sevilla

In the material properties tab of hyperlife, there is the possibility to select 3 surface treatments (Nitrided, shotpeened, coldworked) Nitrided applies a correction factor of 2 while shotpeening and coldworks don't apply any correction factor.

My question is: Why there is the option of apply shotppening or coldwork when the result won't change in any way?

 

solon

Hello,

In general cases, the total correction factor is Csur=Ctreat⋅Cfinish

If treatment type is NITRIDED, then the total correction is Csur=2.0⋅Cfinish(Ctreat=2.0)

If treatment type is SHOT-PEENED or COLD-ROLLED, then the total correction is Csur = 1.0. It means you will ignore the effect of surface finish.

See documentation page:

https://help.altair.com/hwdesktop/hlife/topics/solvers/os/analysis_fatigue_other_factors_r.htm#:~:text=Factors%20Affecting%20Fatigue-,Surface%20Condition%20(Finish%20and%20Treatment),-Surface%20condition%20is