@misc{oliveira_laser_welding_2021, 
author={Oliveira, J., Shen, J., Escobar, J., Salvador, C., Schell, N., Zhou, N., Benafan, O.},
title={Laser welding of H-phase strengthened Ni-rich NiTi-20Zr high temperature shape memory alloy},
year={2021},
howpublished = {journal article},
doi = {https://doi.org/10.1016/j.matdes.2021.109533},
abstract = {Laser welding of a Ni-rich NiTi-20Zr (at.%) high temperature shape memory alloy was performed. The starting base material was aged for 3 h at 550 °C followed by air cooling prior to welding to induce H-phase precipitation. Advanced microstructure characterization encompassing scanning and transmission electron microscopy, coupled with synchrotron X-ray diffraction, were used. Defect-free welds were obtained with a conduction welding mode. The weld thermal cycle altered the microstructure across the heat affected and fusion zones of the joints. The heat affected zone exhibited partial H-phase dissolution, causing a decrease in hardness. In the fusion zone, the H-phase fully dissolved, and the non-equilibrium rapid solidification conditions prevented the H-phase from re-precipitating during cooling, leading to a microstructure resembling that of an as-cast alloy with the same material composition. Mechanical testing revealed that the laser welded samples sustained stresses in the order of 500 MPa and exhibited stress-strain responses comparable to those of the unwelded base material. Thus, this initial study shows new possibilities for using advanced laser joining methods in these alloys.},
note = {Online available at: \url{https://doi.org/10.1016/j.matdes.2021.109533} (DOI). Oliveira, J.; Shen, J.; Escobar, J.; Salvador, C.; Schell, N.; Zhou, N.; Benafan, O.: Laser welding of H-phase strengthened Ni-rich NiTi-20Zr high temperature shape memory alloy. Materials & Design. 2021. vol. 202, 109533. DOI: 10.1016/j.matdes.2021.109533}}