论文部分内容阅读
Diamond impregnated Cu-Fe-Co based saw-blade segments are directly processed by vacuum and pressure-assisted sintering at different temperature,with the purpose of reducing the cobalt content in diamond tools.Copper and iron are used as the bonding elements and co-balt-chrome pre-alloyed powder is used as the hardening phase.Effects of sintering temperature on microstructures and mechanical properties of the sintered matrix and diamond graphitization were investigated by X-ray diffraction analysis,electron probe micro-analyzer,universal testing machine,digital Rockwell hardness tester and Raman scattering analyzer.Results showed that microstructures of the sintered matrix were refined and porosities in the sintered matrix were closed to a more spherical-like shape with the increase of the sintering temperature.Densification,hardness and tensile strength of the matrix sintered at 820 ℃ were 12.75%,2.72% and 156.38% higher than that of the matrix sintered at 740 ℃,respectively.Diamond graphitization was not occurred at 820 ℃.The hardness and the tensile strength rose 32.8% and 13.5%,respectively,after 7.5 h ageing treatment.The matrix densification ascent and the dispersed distribution of Co-Cr pre-alloyed powders contributed a hardness improvement and a tensile strength improvement to the Cu-Fe based matrix.
Diamond impregnated Cu-Fe-Co based saw-blade segments are directly processed by vacuum and pressure-assisted sintering at different temperatures, with the purpose of reducing the cobalt content in diamond tools. Copper and iron are used as bonding elements and co- balt-chrome pre-alloyed powder is used as the hardening phase. Effects of sintering temperature on microstructures and mechanical properties of the sintered matrix and diamond graphitization were investigated by X-ray diffraction analysis, electron probe micro-analyzer, universal testing machine, digital Rockwell hardness tester and Raman scattering analyzer. Results showed that microstructures of the sintered matrix were refined and porosities in the sintered matrix were closed to a more spherical-like shape with the increase of the sintering temperature. Densification, hardness and tensile strength of the matrix sintered at 820 ° C were 12.75%, 2.72% and 156.38% higher than that of the matrix sintered at 740 ° C, respectively. Diamon d graphitization was not occurred at 820 ° C. The hardness and the tensile strength rose 32.8% and 13.5%, respectively, after 7.5 h aging treatment. The matrix densification ascent and the dispersed distribution of Co-Cr pre-alloyed powders contributed a hardness improvement and a tensile strength improvement to the Cu-Fe based matrix.