Cu-Co-Cr-Ni-W系インサート金属を用いたSi₃N₄と高融点金属の接合現象

耐熱性ファインセラミックスの接合に関する研究(第1報)

抄録

Bonding of Si₃N₄ to refractory metals has been investigated using liquid insert metals of copper base alloys. The bonding has been carried out in an electric furnace in vacuum of 6 mPa. Strength of joints was evaluated by tensile-shear tests made at temperature from room temperature to 1073 K.
Copper-Haynes No. 188 alloys which showed good wettability with Si₃N₄ were selected as an insert metal. Strength obtained for joints of Si₃N₄ to Si₃N₄, tungsten, molybdenum, niobium and tantalum were about 160 MPa, 80 MPa, 100 MPa, 60 MPa and 55 MPa, respectively. Strength of joints of Si₃N₄ to tungsten and molybdenum increased with the rise of test temperature from room temperature to 473 K and reached 90 MPa and 100 MPa, respectively.
In the joint of Si₃N₄ to Si₃N₄, voids were observed' in the insert layer except for the insert metal of copper with 20-30%Haynes No. 188 alloys. Liquidus and solidus temperature of insert metals decreased with increasing copper content. The improved fluidity of the insert metal caused by the decrease in the melting temperature seemed to have the effect of preventing the void formation in the insert layer, resulting in improvement of the strength of the joint.