|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||Fracture Properties and Residual Stresses in Small Dimensions
||Oxide-induced Substrate Cracking in Ti and Stainless Steels Driven by Pulsed Laser Irradiation
||Jesus Hector Morales Espejo, David F. Bahr
|On-Site Speaker (Planned)
||Jesus Hector Morales Espejo
Oxide layers grown on Ti6Al4V and 304 stainless steel using pulsed laser irradiation (PLI) at different scan rates on samples were analyzed. These oxides exhibit mudflat cracking, with an increasing crack density formed at faster laser scan rates. The mudflat cracks penetrate into the substrate of both materials, with crack depths between 1 – 6 μm. The cracks do not appear to be significantly influenced by the underlying substrate grain orientation. Residual stresses in the oxides were estimated using several methods. With the elastic and fracture properties of film measured using nanoindentation, a low substrate toughness is inferred, likely due to embrittlement promoted by hydrogen penetrating into the film and substrate during oxide growth; compositional depth profiles were carried out to explain this behavior. An understanding of the cracking phenomenon induced by PLI on both materials and possible mitigation mechanisms will be presented.