1990 Volume 8 Issue 3 Pages 343-349
Three sorts of amorphous metal foil, Fe-Co-Si-B, Fe-Ni-Mo-B and Co-Fe-Ni-Mo-Si-B alloys, were spot-welded by using a stored energy spot welding machine, and examined the tensile shear strength of their single and multiple spot welds.
The former two specimen foils showed insufficient joint strength and fracture occurred at the inside of the weld nugget. The third one showed higher joint strength than the former two and a crack formed at the periphery of the weld nugget and extended into base metal.
Tensile shear strength of multiple spot welds increased with the increase in the number of weld nugget in their own ways. Multiple spot weld of the third foil showed good ductility in bending with tensile shear loading.
X-ray diffraction patterns from the weld nuggets of the former two foils had some peaks indicating crystallization, while the pattern from the third one had only a broad peak.
Both weld nugget thickness and electrode force had not the influence for the prevention of crystallization of the weld nugget in the range of this experimental conditions.
Weldability of amorphous metal foil for stored energy spot welding was not affected by iron content in the foil, but mainly dominated by its chemical constituent.
