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Feb 17
The laser spot welding (LSW) equipment can be used for welding small-sized, metal materials. The parts to be joined are locally melted using Nd: YAG laser and fused together. The laser spot welding equipment (Mastercubo 60, laser all, Italy) is located in the Western Lab and has been established from a DST grant for the micro-fabrication lab.
The physical principle of laser weld uses a beam of electromagnetic waves in phase, photons focalized with optical mediums and concentrated on the piece creating high powers. When the beam shoots the surface the energy is partially reflected and partially absorbed causing the fusion of the material. If the concentration exceeds a certain limit there’s instantaneous vaporization of the base metal in the zone where the beam is more concentrated, in the zone around, instead, there’s melted metal. Metallic vapor at high temperature and pressure pushes laterally the melted and the beam proceeds in the below metal. The hole created is defined as a keyhole.