粉末冶金を利用した高剛性鋼 High Modulus Steel Produced by Powder Metallurgy Process
A new TiB<SUB>2</SUB> particle reinforced ferritic steel with Young's modulus as high as 300GPa has been produced through a powder metallurgy process. This paper discusses the mechanism for providing high performance of the developed material. The phase equilibrium between TiB<SUB>2</SUB> and Fe-Cr-Ti ferritic phases was determined by the CALPHAD method. Based on its thermodynamic stability, which is responsible for maintaining its own high Young's modulus of 540GPa and low density of 4.53g/cc in ferritic matrix, TiB<SUB>2</SUB> particles have been proved to be the best reinforcement for improving isotropic specific Young's modulus of steels. The process designed for the application of the developed material involves power compaction, sintering, and hot forging. Hot working for the material had favorable effects not only on attaining its full densification but also on improving homogeneity of the TiB<SUB>2</SUB> particle dispersion. The Young's modulus of the material agreed exactly with the theoretical one predicted by the non linear law of mixture and the specific Young's modulus could be attained to the double as high as that of conventional steel. The tensile and fatigue strength, and wear resistance were also fairly improved with increase of TiB<SUB>2</SUB> particle dispersion.
粉体および粉末冶金 45(5), 399-404, 1998-05-15
Japan Society of Powder and Powder Metallurgy