Abstract
SUS304 stainless steel wire was micro spot melted by using YAG laser to investigate the applicabilty to the fabrication of biomedical devices. Effects of laser conditions such as laser power input or pulse duration were investigated on the microstructure and tensile strength of spot melted wires. Width of the melted metal decreased by laser irradiation with a shorter pulse duration and was about 0.3 mm for the 0.35 mm diameter wires. On the contrary, laser spot melting with a shorter pulse duration needed more precise control of laser conditions to achieve the sound melting free from burn out of the samples. Similarly, melting of thinner wire needed more precise control of laser conditions. Melted metal exhibited a rapidly quenched austenite cell microstructure with a cell size of less than about 5 \\micron. Tensile strength of the spot melted wires was 660 MPa, which was almost the same as that of annealed base materials. Besides, corrosion resistance in a quasi biological environment was hardly degraded by spot melting. Crosswise joints was also successfully prepared by laser spot welding of wires, suggesting the laser micro welding is applicable to the fabrication of biomedical devices.
