摘要
为研究SiC颗粒形貌对SiC_p/Al复合材料热性能的影响,采用水刀对颗粒进行预处理以圆整颗粒的尖角,随后通过挤压浸渗工艺制备了67vol%SiC_p/Al复合材料。同时,采用DEM模型、Kerner模型、Turner模型和2D有限元模型分别对复合材料的导热率、热膨胀性能进行了预测。对比模拟结果和实验结果说明,2D有限元模型的模拟结果与实验结果更为接近;SiC颗粒形貌对本研究复合材料的导热、膨胀性能有直接影响。长径比较小的颗粒有利于热量的均匀扩散,所制备的复合材料具有更高的导热率,同时导热率和热膨胀系数具有各向同性;长径比较大颗粒制备的复合材料由于热量在长度方向和径向的传热具有差异,从而导致其导热率和热膨胀性能具有各向异性。
In order to investigate the effect of morphology of SiC particles on the thermal conductivity, the sharp edge of the coarse SiC particles was polished by water jet Saw, SiCp/Al composites with 67% volume fraction of SiC particles was fabricated by pressure infiltrating. Meanwhile the thermal conductivity and the coefficient of thermal expansion was predicted by the different effective medium（DEM）, Kerner, Turner analysis and 2D finite element molding（FEM）respectively. The prediction results show that the 2D FEM results match the experiment results perfectly. The comparison between the 2D FEM results and experimental results shows that the thermal conductivity and the coefficient of thermal expansion are affected by the morphology of SiC particles. The thermal conductivity of SiCp/Al composites with lower ratio of coarse particles is higher than that with higher ratio of coarse particles, meanwhile the thermal conductivity and the coefficient of thermal expansion of SiCp/Al composites with lower ratio of coarse particles has small fluctuation, conversely the thermal conductivity and the coefficient of thermal expansion of SiCp/Al composites with higher ratio of coarse particles has large fluctuation.
出处
《铸造技术》
CAS
北大核心
2016年第6期1090-1094,共5页
Foundry Technology
