Surface integrity and superelastic response of additively manufactured Nitinol after heat treatment and finish machining

This paper explores the feasibility of adopting additive manufacturing followed by heat treatment and finish machining to fabricate Nitinol components with enhanced surface integrity and more favourable superelastic characteristics. The most suitable manufacturing approach is demonstrated to achieve these characteristics by establishing appropriate bulk and surface conditioning. New insights are presented on the correlation of process chain parameters and Nitinol superelastic response focusing on the role of the microstructural constituents and surface integrity generated from finish machining with different cooling conditions. The wear behaviour of Nitinol components fabricated by the proposed manufacturing approach is also evaluated to demonstrate bearing applications.