Micro resistance spot welding offers a simpler and more cost-effective alternative to current technologies used for welding NiTi alloys. Since this area is still under-researched, we focused on analyzing the mechanical properties of the material under various welding parameters in our thesis. We employed the Design of Experiments method, where we first defined the parametric window through preliminary analysis and then designed an experiment, adjusting welding current and time at three levels. After welding, we conducted metallographic analysis and tensile-shear testing, demonstrating the preservation of superelasticity, albeit at slightly lower loads compared to the base material. With a maximum elongation of 4.3 %, we achieved better results than those in previous studies using the same welding technique. The DoE method allowed us to determine the optimal welding parameters, with a current of 3.5 kA and a welding time of 15 ms. In our thesis, we have demonstrated that the micro resistance spot welding process can produce high-quality and reproducible welds that retain the superelasticity of NiTi alloys to a certain extent.
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