Densification behavior due to sintering plays an important role in the mechanical properties and size accuracy of PM components,especially of the micro powder injection molding(μ-MIM)components.Based on the microstructure evolution,micro gears with addendum circle diameter of 900μm fabricated by μ-MIM technique with carbonyl iron powder and wax-based binder substrate were investigated during sintering process.It was found that the micro gears exhibited a faster sintering featured with larger grain and less pores on microstructure together with greater shrinkage and higher density when compared with the substrate,which demonstrated one of the typical characteristics of the micro powder injection molding.The observations on microstructure were analyzed and reasons causing the phenomenon were unraveled in this case.
Xu Hui Zhang Liu Yin Haiqing Elder Sharon Khan Dil Faraz Zheng Qingjun Qu Xuanhui
Collaborative Innovation Center of Steel Technology,University of Science and Technology Beijing,Bei Collaborative Innovation Center of Steel Technology,University of Science and Technology Beijing,Bei The College of Information Sciences and Technology,The Pennsylvania State University,University Park Department of Physics,University of Science and Technology Bannu,Bannu 28100,Pakistan Kennametal Inc.,1600 Technology Way Latrobe,PA,15650 USA Collaborative Innovation Center of Steel Technology,University of Science and Technology Beijing,Bei