金刚石与磨料磨具工程2026，Vol.46Issue(4)：427-436,10.DOI:10.13394/j.cnki.jgszz.2024.0169
金刚石/铝复合材料界面处Al4C3的离散分布调控
Regulation of discrete distribution of Al4C3 at interface of diamond/Al composites
摘要
Abstract
Objectives:Diamond/Al composites have shown great potential in thermal management applications in fields such as electronic packaging and aerospace due to their excellent thermal conductivity,low thermal expansion coefficient,and lightweight.In diamond/Al composites,Al4C3 acts as a bridge connecting diamond and the aluminum matrix.Its distribution characteristics at the interface play a decisive role in the interfacial bonding between diamond and aluminum,as well as in the thermal conductivity of the composite material.Methods:In this study,diamond/Al composites are prepared by gas pressure infiltration.The variation trends in the grain size and coverage rate of Al4C3 on different crystal faces of diamond particles at different infiltration temperatures(750,800,850,and 900℃)are investigated,as well as their impacts on the interfacial bonding and thermal conductivities of the composites.Scanning electron microscopy(SEM),energy-dispersive X-ray spectroscopy(EDS),X-ray diffraction(XRD),and Raman spectroscopy are used to analyze the microstructures of the composite interfaces and quantify the grain size and coverage rate of Al4C3 on different crystal faces of diamond particles under various infiltration temperatures.Additionally,the density of the composites is determined according to Archimedes'principle,and their thermal conductivity is measured using the laser flash method to assess the interfacial bonding conditions and thermal conductivities of the composites at different infiltration temperatures.Results:As the infiltration temperature increases,the interfacial bonding strength of the composites gradually increases,and the proportion of intergranular fracture in the cross-sectional morphology also increases.Al4C3 at the composite interface exhibits discrete distribution characteristics at all infiltration temperatures.With increasing infiltration temperature,the grain size and coverage rate of Al4C3 increase.At lower infiltration temperatures,Al4C3 tends to form more readily on the diamond(100)crystal plane;at higher infiltration temperatures,Al4C3 gradually tends to form more on the diamond(111)crystal plane.This change in distribution characteristics is related to the energies of different diamond crystal planes and the diffusion behavior of carbon atoms in aluminum.Meanwhile,as the infiltration temperature increases,the densities and thermal conductivities of the composites first increase and then decrease,which is closely related to the distribution characteristics of Al4C3 at the interface.At lower infiltration temperatures,the insufficient Al4C3 at the composite interface cannot effectively improve the interfacial bonding between diamond and aluminum.At higher infiltration temperatures,excessive Al4C3 at the composite interface provides excessive interfacial thermal resistance.When the infiltration temperature is 850℃,the average grain size of the Al4C3 on the diamond(100)crystal plane is 2.97 μm,with a coverage rate of about 47.94%;while on the(111)crystal plane,the average grain size of the Al4C3 is 3.83 μm,with a coverage rate of about 82.27%.At this temperature,the composite achieves the best interfacial bonding state,with a thermal conductivity reaching 731 W/(m·K).Conclusions:This study achieves an optimized discrete distribution of Al4C3 at the interface of diamond/Al composites by regulating the gas pressure infiltration process,investigates the growth of Al4C3 on different crystal faces of diamond,and studies the relationship between the distribution of Al4C3 at different infiltration temperatures and the interfacial bonding of the composites.When the infiltration temperature is 850℃,the composite exhibits the best interfacial bonding state,with a thermal conductivity of 731 W/(m·K).This study provides experimental evidence and theoretical guidance for the discrete interfacial modification of diamond-based metal matrix composites.关键词
界面优化/气压熔渗/热导率/金刚石/铝复合材料Key words
interface optimization/gas pressure infiltration method/thermal conductivity/diamond/Al composite material分类
通用工业技术引用本文复制引用
姚远卓,焦增凯,吴建杰,黄文杰,马莉,魏秋平..金刚石/铝复合材料界面处Al4C3的离散分布调控[J].金刚石与磨料磨具工程,2026,46(4):427-436,10.基金项目
国家十四五重点研究发展计划(2021YFB3701800) （2021YFB3701800）
国家自然科学基金(52071345) （52071345）
湖南省自然科学基金(2023JJ40722). （2023JJ40722）
