WE Colloquium: Joao Oliveira, Laser Welding of Shape Memory Alloys

Post-Doctoral Researcher, Welding Engineering, The Ohio State University

All dates for this event occur in the past.

111 EJTC
1248 Arthur Adams Dr.
Columbus, OH 43221
United States

Abstract

Shape memory alloys are known by their functional properties: shape memory effect and superelasticity. These materials are used in different industries such as biomedical, aerospace and automotive. However, their poor workability limits the design flexibility thus restricting applications requiring complex shapes.

Laser welding is currently the most used joining technique for these materials for both similar and dissimilar combinations.

In this presentation, the microstructural analysis and mechanical behavior of (NiTi/NiTi) and dissimilar (NiTi/Ti6A4lV, using Nb interlayer) laser welded joints will be present. Microstructural characterization was performed using synchrotron X-ray diffraction (for fine probing of the microstructure) and transmission electron microscopy. Mechanical behavior was assessed by means of load/unload cycling tests to analyze the superelasticity of the joints.

Finally, the first known results on laser welding of Cu-based shape memory alloys and the effect of post-weld heat treatments are presented.

Bio

João Pedro Oliveira is a postdoctoral researcher at the Department of Materials Science and Engineering, Welding Engineering Program, at The Ohio State University since September. His research interests include welding of shape memory alloys, laser processing, structural characterization using synchrotron X-ray diffraction and in-situ combined techniques. Before joining OSU, João earned his PhD in Materials Science and Engineering with his thesis entitled “Laser welding of shape memory alloys”, in Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Portugal. He is author and co-author of 15 peer-reviewed papers and 1 book on welding of shape memory alloys.