耐高温金属与硬质合金pdf..doc

Int. Journal of Refractory Metals and Hard Materials 41 (2013) 85–89 Contents lists available at ScienceDirect Int. Journal of Refractory Metals and Hard Materials j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / I J R M H M Fabrication of diamond particles reinforced Al-matrix composites by hot-press sintering Jianping Long, Xin Li , Dedi Fang, Peng Peng, Qiang He College of Materials and Chemistry Chemical Engineering, Chengdu University of Technology, Chengdu 610059, Peoples Republic of China  a r t i c l e i n f o Article history: Received 22 October 2012 Accepted 8 February 2013 Keywords: Vacuum hot-pressing sintering Diamond/Al Electronic packaging Thermal conductivity Coefficient of thermal expansion  a b s t r a c t Al-matrix composites reinforced by 50 vol.% diamond particles under a 60 MPa sintering pressure were fab-ricated by a vacuum hot-pressing method. The composite obtained a relative density of 96.5%. The coefficient of thermal expansion (CTE) and the thermal conductivity (TC) of the diamond/Al composites were measured by the laser flash method and differential dilatometry, respectively. Results showed that diamond/Al composites have high TC and low CTE with high sintering pressure (60 MPa) and high volume fractions of diamond particles (50 vol.%). The TC of the 50 vol.% diamond/Al composite was 321 W/mK, which is 112 W/mK higher than that of pure Al (209 W/mK). At temperatures ranging from 298 K to 573 K, the com-posite obtained low CTEs in the range of 13.2 × 10?6/K to 8.3 × 10?6/K, which satisfied the CTE of electronic packaging materials. The CTE values obtained in the experiment were approximately equal to the CTE calcu-lated by the Kerner model [17]. The effects of volume fractions of diamond particles and sintering pressure on the density, TC, and CTE of diamond/Al composites were investigated. ? 2013 Elsevier Ltd. All rights reserved.  1. Introduction Both miniaturi