Effects of local phase conversion on the tensile loading of pulsed Nd:YAG laser processed Nitinol

The unique material properties of Nitinol, such as its shape memory effect, pseudoelasticity and biocompatiblility, make it ideal for medical device applications. However, reported adverse effects during laser processing of Nitinol have severely impeded its deployment. The current article details some key findings associated with local phase conversion resulting from pulsed Nd:YAG laser processing of Nitinol (Ni-49.2 at.% Ti). Results revealed changes to room temperature phases of the processed metal when compared to the base material, which also affect the tensile properties of Nitinol.

Research highlights▶ DSC results revealed high temperature transformation peaks caused by local phase conversion induced by laser processing. ▶ XRD analysis showed only austenite in the base metal and added martensite peaks in the melted metal. ▶ TEM observation confirmed the presence of room temperature martensite within the processed zone.