Influence of Grit Blasting on Residual Stress Depth Profile and Dislocation Density in Different Metallic Substrates
Abstract
This work deals with the effect of grit blasting on the surface and in-depth properties of a number of commercially available metals/alloys, i.e., low carbon steel, C45 steel, SS316, Ti-6Al-4V, Inconel 718, and Hastelloy X. The residual stress depth profile and dislocation density of the specimens were determined using X-ray diffraction. A substantial increase in dislocation density was observed after grit blasting. A transmission electron microscope was utilized to observe the dislocation structure in a grit-blasted specimen. Strain hardening was also observed at the blasted surface owing to dislocation interaction and entanglement. The hardness profile followed a trend similar to that of dislocation density along the depth of grit-blasted low carbon steel. Moreover, compressive residual stress is induced in the blasted surface having a maximum value at a certain depth. The maximum induced compressive residual stress was found to have a good correlation with the Johnson-Cook flow stress. Moreover, the depth of the affected layer and the increase in hardness were found to depend on the yield strength and the strain hardening exponent of the materials, respectively. A plastic deformation-induced phase transformation from austenite to martensite was also identified in the case of SS316.
- Publication:
-
Metallurgical and Materials Transactions A
- Pub Date:
- January 2021
- DOI:
- 10.1007/s11661-020-06055-x
- Bibcode:
- 2021MMTA...52...65G