基于SPS烧结的M42/45钢双金属接头及性能

利用放电等离子烧结技术(SPS)研究了M42粉末高速钢/45钢双金属连接技术,分析了连接接头的界面形貌,测试了连接接头的界面结合强度.结果表明:在970℃×10 min×70 MPa烧结工艺下,可一次性实现M42粉末高速钢的烧结及其与45钢的连接;接头的M42粉末冶金高速钢部分,显微组织均匀,碳化物细小、无偏析,经工艺1180℃×5 min×550℃×1 h热处理后,硬度达到67.36 HRC;M42/45钢连接接头组织致密且均匀,界面两侧有元素扩散,属冶金结合,界面结合强度可达到550 MPa.

Fabrication of M42 P/M high speed steel/45 steel bimetal joints by spark plasma sintering technique

One-step fabrication of bimetal joints consisting of M42 powder metallurgy high speed steel (P/M HSS) and 45 steel (M42/45) via spark plasma sintering (SPS) technique is reported.The microstructure of joint interfaces were characterized and the mechanical properties were measured.It is found that fabrication of M42/45 joints is accomplished by spark plasma sintering at 970 ℃ and 70 MPa for 10 min.The as-fabricated M42 P/M HSS,which plays as the working parts of the bimetal,exhibits the uniform microstructure with fine grain size and without carbide segregation.Its Rockwell hardness reaches 67.36 HRC after quenching at 1180 ℃ for 5 min and ternary tempering at 550 ℃ for 1 h,which is much higher than that of conventional sintered ones.The tensile strength of the bimetal joint is up to 550 MPa,which is attributed to the sound interface with few defects obtained by spark plasma sintering.Current work provides a facile and useful method for fabrication of bimetal joints with high quality,which benefits the fabrication of composites to save the cost of metals acting as working parts.