Effect of a Prestrain-Surface Layer Elimination Process on Low Cycle Fatigue Life.
Final rept. 20 Feb 75-20 Mar 76,
GENERAL MOTORS CORP INDIANAPOLIS IND DETROIT DIESEL ALLISON DIV
Pagination or Media Count:
Low cycle fatigue specimens of Ti 6Al-4V and a martensitic stainless steel H46, were tested to determine the effect of a prestraining-surface layer elimination process on the low cycle fatigue life. Results of axial strain controlled tests conducted at ambient temperature, using a constant strain range after prestraining for specimens with and without a surface layer elimination process, showed no significant improvements over those of baseline tests for Ti 6Al-4V. However, H46 material did show an improvement as a result of a surface layer elimination process. The improvement was approximately 15 for both crack initiation and failure. The increase in life was attributed to an increase in the proportional limit which in turn decreased the amount of plastic strain. Author
- Metallurgy and Metallography