摘要
Warm compaction process of pure iron powder was investigated. Due to the existence of elastic, plastic and thermal strains, a coupled mechanical and thermal model was applied. The elasto-plastic constitutive equations for powder material were developed based on ellipsoidal yield criterion and continuum theory. The constitutive equations were integrated into the constitutive integral arithmetic and solved employing incremental iterative solution strategy. The yield strength of iron powder was obtained according to the tensile experiments. When the compaction temperature was raised to 130 ℃, the yield strength of iron powder metal drops to 85% of room temperature value. Modified coulomb friction law is applied and the simulation results show that friction was an important factor resulting in the inhomogeneous relative density and reverse-density distribution phenomena in the regions near the die wall and the symmetrical axis.
Warm compaction process of pure iron powder was investigated. Due to the existence of elastic, plastic and thermal strains, a coupled mechanical and thermal model was applied. The elasto-plastic constitutive equations for powder material were developed based on ellipsoidal yield criterion and continuum theory. The constitutive equations were integrated into the constitutive integral arithmetic and solved employing incremental iterative solution strategy. The yield strength of iron powder was obtained according to the tensile experiments. When the compaction temperature was raised to 130 ℃, the yield strength of iron powder metal drops to 85% of room temperature value. Modified coulomb friction law is applied and the simulation results show that friction was an important factor resulting in the inhomogeneous relative density and reverse-density distribution phenomena in the regions near the die wall and the symmetrical axis.
出处
《中国有色金属学会会刊：英文版》
EI
CSCD
2006年第2期311-315,共5页
Transactions of Nonferrous Metals Society of China
基金
Project(50325516) supported by the National Foundation of China for Outstanding Young Scientists
Project(50135020) supported by the National Natural Science Foundation of China
Project(CG2003-GA005) supported by China Education and Research Grid (China Grid)
关键词
粉末金属
温压
相对密度
有限元
热模拟
powder metal
warm compaction, finite element method
friction, relative density
