Modification of oil-wax-polypropylene based binder by EPDM for MIM
ZHANG Chenming1, LU Renwei2, YANG Zhongchen2, LI Duxin1
1. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China; 2. Changsha Juzhong Metallurgy Technology Co. Ltd, Changsha 410000, China
Abstract EPDM was used as modifier in oil-wax-polypropylene based binder system for MIM in this paper. Four formulations of binder and 17-4PH stainless steel powder were mixed to prepare feedstocks and then injection molding. The effects of EPDM content on the rheological characteristics of feedstocks, properties of green parts as well as degreasing properties were studied. The results show that the viscosity of feedstock increases with EPDM addition. With the increase of EPDM content, the impact energy of green parts increases as well as bending strength decreases. The optimal mechanical properties of green parts are obtained when EPDM content is 2%. After seven cycles, the impact energy is 2.048 J, the bending strength is 6.3 MPa. In addition, the speed of solvent debinding increases with EPDM addition. Carbon content and oxygen content of debound parts can keep in reasonable range.
ZHANG Chenming,LU Renwei,YANG Zhongchen, et al. Modification of oil-wax-polypropylene based binder by EPDM for MIM[J]. Materials Science and Engineering of Powder Metallurgy, 2018, 23(6): 619-623.
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2018, Vol. 23 
