Preparation And Properties Of ?-SiCp/Al Composite Used For Electronic Packaging

?-SiCp/Al composite for electronic packaging,owned high thermal conductivity,low thermal expansion,a certain strength?stiffness,low density and other excellent features,used in power electronic substrate and substrate materials,match well with electronic chips.In this paper,70%vol.?-SiCp/Al composites were prepared by powder metallurgy-hot pressing sintering.The effects of vacuum hot pressing sintering parameters,?-SiCp particle size,?-SiCp particle size composition and different matrix on the properties of the composites were studied.The materials were characterized by XRD,SEM and EDS.CTE,relative density,bending strength and other numerical measurements,and further analysis of the composite material thermal properties and mechanical properties,to establish the most suitable composite sintering parameters are 690 ?,30MPa pressure under the insulation 1.5h.(1)oxidation at 850 ? for 1h and pickling treatment,?-SiCp surface impurities,fine particles and so clear,to obtain a better P-SiCp morphology.(2)using the best ball milling process for the ball ratio of 1:2.5,speed 260r/min,ball 8h,in the original reinforcement material less broken case to get evenly dispersed composite powder.(3)Addition of Si to effectively control the degree of interfacial reaction;composite material is organized,the level is clear,the interface generates a small amount of A14C3 and MgA1204,improve the interfacial bonding strength of the composite.(4)Composites with different Si elements,the thermal conductivity increases first and then decreases with the increase of Si content,and the optimum amount of Si is 10%.(5)The relative density,TC and CTE of the composites were affected by the size of the reinforced body.The relative density,TC and CTE of the composites were increased when the particle size was increased.Under the optimum sintering process,The relative density,TC value and CTE value of 70%?-SiCp/Al composites were higher than that of single particle size,and the TC and CTE values increased with the coarsegrain mass ratio improved.When the ratio of ?-SiCp to 40?m and 3.5?m was 7:1,the relative density,TC value and CTE value of the composites were 97.7%and 157.4W/m,respectively.× 10-6/K,are higher than the mass ratio of 3:1 situation.Considering the ratio of 20?m and 3.5?m with 7:1 mass ratio,the composites have good comprehensive performance.(6)The fracture mode of the composites is the cleavage fracture of the reinforced ?-SiCp and the small Al-shaped matrix fracture.In summary,the method can be used to obtain the comprehensive performance to meet the requirements of electronic packaging with ?-SiCp/Al composite materials.