Early Detection of Damage of Inconel 718 with the Use of Strain-Hardening Cross-Effect

Abstract

Indentation tests were used for early detection of deformation-induced damage of Inconel 718. Damage was produced in a controlled manner using specially designed specimens with a variable width of the gage part. Static tension, LCF, and HCF tests were performed to induce material damage. Accumulated plastic strain intensity was used as the reference measure of deformation-induced damage. Detection of damage progress in its early phase was based on the use of strain-hardening cross-effect. Experimentally determined correlation of hardness and indentation work with reference damage parameter was analyzed. The results of our analysis lead to the conclusion that the proposed experimental procedure is useful for the detection of deformation-induced damage in the early stage of the process.

Keywords

• Inconel 718
• instrumented indentation tests
• fatigue damage
• strain-hardening cross-effect