Simulation of Removing Autofrettage-induced Residual Stress Loaded Layers by Finite Element Analysis

Hydraulic Autofrettage is a process to selectively induce beneficial compressive residual stresses in failure critical areas of internally pressurized components. The compressive residual stresses are present over several millimeters in the material depth. Following post-machining operations remove a portion of these residual stress loaded layers and lead to a redistribution of the residual stresses. Additionally, machining is known to introduce residual stresses itself. This paper uses a finite element method approach to discuss the effect of the material removal and as a consequence its impact on the layout of the technical process chain. First of all, the material removal is considered to be completely elastic by simply deleting the corresponding elements. Secondly, it is considered by a real interaction between the cutting tool and the material within an explicit 3D simulation.