PURPOSE: To efficiently manufacture an Fe-Ni low expansion alloy wire high in strength and small in dispersion without carrying out vacuum annealing.
CONSTITUTION: In the method for manufacturing the Fe-Ni low expansion alloy wire where a desired number of times of annealing, scalping, and wire drawing is implemented respectively, the annealing is carried out below 650°C in the atmosphere before the scalping and the wire drawing after the atmospheric annealing is carried out at a wire drawing speed below 60m/min. Since the atmospheric annealing is carried out at a low temperature below 650°C, variation of precipitation state of alloy elements is small and since the wire drawing is carried out at a low speed and working exothermic phenomenon is restrained, an effect exerted on a quantity of working strain by the working temperature difference is small, therefore, an ununiform strain is not generated on the Fe-Ni low expansion alloy wire rod and the vacuum annealing to this wire rod can be omitted.
OKADA TETSUYA
SUKEGAWA TAKASHI
KISE KEISUKE
