节点文献
金刚石/铜复合材料制备的研究
【作者】 邓丽芳；
【导师】 朱心昆；
【作者基本信息】 昆明理工大学 ， 材料学， 2009， 硕士
【摘要】 随着信息化时代的迅速发展,传统的电子封装材料已经不能满足现代集成电路以及各类电器元件电子封装的发展要求。新型的封装材料要求具备轻质、高热导、低膨胀的性能,金刚石/铜复合材料综合了铜和增强体的优良特性而具有较好的导热和可调的热膨胀系数,具有非常广阔的应用前景。但目前有关该体系的理论研究与应用研究尚不成熟,迫切需要进行更多的探索和研究。本论文采用粉末冶金工艺(复压复烧工艺、粉末真空包套热锻造工艺及粉末真空包套热挤压工艺)制备以单晶金刚石颗粒为增强体的金刚石/铜复合材料。利用XRD、金相显微镜、扫描电镜对复合材料的微观组织特征进行了研究,并测试了复合材料的热膨胀系数。着重研究了各成形工艺对复合材料致密度的影响,并探讨了热膨胀系数的影响因素。对于金刚石粒度40μm,体积含量70%的复合材料采用不同的制备工艺得出：复压复烧工艺制备的复合材料在890℃烧结8小时其致密度达到82.82%,其在50-100℃时热膨胀系数达到6.4～7.5×10-6/K；粉末真空包套热锻工艺制备的复合材料其致密度低至79.584-80.692%,热膨胀系数达到11.315-11.647×10-6/K；粉末真空包套热挤压制备的40gm,体积含量70%的复合材料致密度为70.125%,其热膨胀系数达7.864×10-6/K。通过对热膨胀系数的影响因素分析得出：热膨胀系数随温度的升高和金刚石颗粒度的增加而升高,随金刚石体积分数的增加而降低。通过对制备出的金刚石/铜复合材料的热膨胀系数进行理论模型计算,发现不同成形工艺所得的复合材料的实验值均高于理论模型的计算值,理论模型中ROM混合规则和Kerner模型的计算值在金刚石体积分数较低的情况下与实测值相对较为接近,当金刚石体积含量增大时模型的计算值低于实测值。
【Abstract】 The electronic packaging technology in modern ICs and other electrical components has a specification-advanced demand for packaging materials. Advanced packaging materials demand lightweight, higher thermal conductivity (TC) and lower coefficient of thermal expansion (CTE). Diamond/Cu composites have a promising potential in future application due to their good combination of TC and tailorable CTE. But previous research of Diamond/Cu system is still not satisfied both in the theories and engineering aspects.Monocrystalline diamond powder was used in present work, Diamond/Cu composites were prepared by powder metallurgy under the different molding process (repressing and re-sintering technology, vacuum packing hot forging technology, vacuum packing hot extrusion technology). The microstructure of the diamond/Cu composites were observed by XRD, Metallurgical Microscopy and SEM methods. The coefficient of thermal expansion and density of composites were measured. The effect of different molding process technology on the density of samples was analyzed. The effects of volume fraction and powder size of diamond on the coefficient of thermal expansion were also discussed.By analying the densiy and the coefficient thernal expansion of the composites of 40μm 70vol.%diamond/Cu prepared by three different technologies, the results showed that the relative density could be gained to 82.82% and the coefficient thernal expansion 6.4-7.5×10"6/K at 50～100℃prepared by repressing and re-sintering technology (singtering temperature:890℃;singtering time:8h);the relative densiy 79.584～80.692% and the coefficient thernal expansion 11.315～11.647×10-6/K prepared by vacuum packing hot forging technology and the relative densiy 70.125%and the coefficient thernal expansion 7.864×10-6/K prepared by vacuum packing hot extrusion technology.The coefficient of thermal expansion of the composites were tested and analyzed. The results showed that the coefficient of thermal expansion increased with the temperature lighted, the diamond particle size increased and the volume fraction of diamond reducedThrough theoretical calculation, the coefficient of thermal expansion reduced with the increasing of the relative density of composites, the volume fraction of diamond and the decreasing of diamond particle size were found. Calculation value is smaller in comparison with measured. The experiment data were more closer ROM and Kerner model with lower diamond volume fraction and were higher than throretical data with higher diamong volume fraction.