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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