鋳ぐるみ加工被覆したMoの電熱線への適用

抄録

Molybdenum was coated with a JIS electric heating material (Nichrome alloy) and cobalt-base heat-resistant alloy (S-816) by casting and was then drawn to a diameter of 0.5 mm. On the applicability of these wires to the electric heating wire, some properties which are required for electric heating wire were compared with the commercial JIS electric heating wires, Ni, Cr and Ni-Cr multi-electroplated molybdenum wires and Al and Al-Si alloy dipped molybdenum wires. The life of the composite material is equal and/or superior to the JIS Nichrome wire up to 1250°C, but deteriorated at 1300°C. The tensile strength of the material is almost equal to the JIS electric heating wires at room temperature, but about 2 to 2.5 times larger at 1200°C. The electrical resistivity of the material is considerably small as compared with the JIS electric heating wire at room temperature, but becomes almost equal at 1000°C because of its high temperature coefficient. The change in electrical resistivity of the material after its use for a long period is almost equal to the JIS electric heating wire. This result shows that the material is very stable. In conclusion, this composite-material shows an ability comparable to the JIS electric heating wire in air up to 1250°C and is advantageous for a particular purpose in view of its superior high temperature strength.