| 摘要 |
PURPOSE:To relax the residual stress by forming a metallic shaft, which is to be connected to a ceramic-made blade wheel, with a large-diameter element with a non-hardened surface and a small-diameter element with a hardened surface. CONSTITUTION:To the end face of a blade wheel shaft 52 of a ceramic-made blade wheel 53 is brazed a large-diameter element 54 consisting of a low Young's modulus material or a low expansion material with a non-hardened surface, and further to the rear end face of this large-diameter element 54 is brazed a small-diameter element 56 which has at least a surface-hardened sliding section with the bearing. In this way, on the joint area of the blade wheel 53 with the large-diameter element 54, a deformation or strain caused by the differences in thermal expansion is restrained, and the joint strength is increased with a braizing material reservoir 55 being formed; therefore, the residual stress such as deformation, strain, etc. can be relaxed. |
