各種耐熱合金で鋳ぐるみ加工被覆したMoのクリープ・ラプチャー強さについて

抄録

Molybdenum, coated with nickel-base, iron-base and cobalt-base heat-resistant alloys by casting, was hot-worked for its high temperature uses under the stressed condition in air, and the results of the creep-rupture test were compared. When S-816 cobalt-base heat-resistant alloy was used as coating materials, the bonding by fusion between molybdenum and S-816 is considerably inferior to the others. It was known that one of the reasons is that the coefficient of melting rates of molybdenum into molten S-816 alloy is especially small. Molybdenum coated with any of the heat-resistant alloys can be best swaged at 1150°C, and cracking on the molybdenum part and the diffusion zone did rarely occur. In the creep-rupture strength at 1000°C in air, molybdenum coated with S-816 was strongest for the large stress and short time, while molybdenum coated with Nimonic 90 nickel-base alloy was strongest for the small stress and long time.