We rough machined the Incoloy 909 in the solution condition. Then perform aging heat treatment, final machining and FPI. However many linear indication found and those indication is about 0.010 inch to 0.020 inch. We had machined this material for many years and never encounter this problem. We do not know how this occurred.
Click to enlarge
Are those linear indications caused by machining, heat treatment process, forging process or material problems?
Has anyone suggest us a right way to solve this trouble?
Thanks in advance!
Simon