Abstract
Fe–Cr–Co alloys containing less than 30% chromium and less than 70% cobalt were heated in vacuum over the temperature range of 500∼1000°C for 1 h and then furnace-cooled after cold-drawing by about 98% reduction in area. Measurements of the strain gauge factor and electrical properties at room temperature were carried out for the alloys.
Generally, with increasing annealing temperature, the strain gauge factors of the Fe–Cr–Co alloys decreased gradually to a minimum at about 500°C and increased sharply to a maximum at 800°C. In this system, an Fe-15% Cr-30% Co alloy showed a maximum strain gauge factor of 7.3, and an electrical resistivity of 0.78 μΩm at room temperature and its temperature coefficient of 10.0×10−4/°C. The thermo-electromotive force relative to copper was −1.2 μV/°C for this alloy.
