| Popis: |
The microstructure and mechanical properties of a Co-Cr-W-Mo superalloy used for the driving mechanism of nuclear power station were investigated. This alloy was strengthened by W and Mo elements and carbides for high hardness, and an excellent wear resistance was achieved by the high content of carbides. Also, this alloy was of excellent hot-corrosion resistance due to the addition of 29 wt. % Cr. The as-cast alloy was equiaxed, and consisted mainly of γ-Co solid solution, γ/M7C3 eutectics and Cr-rich M7C3 carbides. The Rockwell hardness was up to 37 - 40. The alloy presented high tensile strength, and the fractography of tensile ruptured specimens was characterized obviously by the interdendritic fracture. |
