1407 マイクロメカニックスによる金属/セラミックス混合粉末焼結特性の解析(S09-2 粉末成形とその評価II,21世紀地球環境革命の機械工学:人・マイクロナノ・エネルギー・環境)

抄録

In metal/ceramic graded powder compacts during sintering, the difference in shrinkage among the layers often causes distortions or cracking. To clarify the constitutive response of the heterogeneous powder compacts, a micromechanics model for sintering is proposed. The sintering stress as well as the viscosity of the powder mixtures is expressed by using Eshelby's equivalent inclusion method and Mori-Tanaka's mean-field theory. The variation in densification behavior with metal/ceramic mixing ratio computed by the proposed model is compared with the experimental data for Ni/Al_2O_3 system. The present model can reproduce the decrease in sintering rate of the powder mixtures, which remarkably appears in the Ni/Al_2O_3 powder compacts with small amount of Al_2O_3.