CAJ | 학술논문

采用挤压铸造法制备粒径为5μm、体积分数为50%的金刚石/2024Al 复合材料。退火处理后对其金相组织界面反应、界面结合情况以及金刚石颗粒的内部缺陷进行观察与分析，并对其热物理性能进行测试与研究。结果表明，金刚石/2024Al 复合材料的组织致密，无明显的气孔、夹杂等缺陷；颗粒为不规则多边形，有棱角，分布比较均匀。透射电镜观察表明，部分金刚石颗粒内部有位错和层错存在，而2024Al 基体中的位错密度较大，金刚石/2024Al界面处有较多的界面反应物生成，可能为Al2Cu。复合材料在20~100°C温度区间内的平均热膨胀系数为8.5×10-6°C-1，退火处理的复合材料其热膨胀系数有一定程度的降低；随着温度的升高，复合材料的平均热膨胀系数也呈现增加的趋势。复合材料的热导率约为100 W/(m·K)，退火处理能够提高复合材料的热导率。
채용제압주조법제비립경위5μm、체적분수위50%적금강석/2024Al 복합재료。퇴화처리후대기금상조직계면반응、계면결합정황이급금강석과립적내부결함진행관찰여분석，병대기열물이성능진행측시여연구。결과표명，금강석/2024Al 복합재료적조직치밀，무명현적기공、협잡등결함；과립위불규칙다변형，유릉각，분포비교균균。투사전경관찰표명，부분금강석과립내부유위착화층착존재，이2024Al 기체중적위착밀도교대，금강석/2024Al계면처유교다적계면반응물생성，가능위Al2Cu。복합재료재20~100°C온도구간내적평균열팽창계수위8.5×10-6°C-1，퇴화처리적복합재료기열팽창계수유일정정도적강저；수착온도적승고，복합재료적평균열팽창계수야정현증가적추세。복합재료적열도솔약위100 W/(m·K)，퇴화처리능구제고복합재료적열도솔。
50%diamond particle (5μm) reinforced 2024 aluminum matrix (diamond/2024 Al) composites were prepared by pressure infiltration method. Diamond particles were distributed uniformly without any particle clustering, and no apparent porosities or significant casting defects were observed in the composites. The diamond-Al interfaces of as-cast and annealed diamond/2024 Al composites were clean, smooth and free from interfacial reaction product. However, a large number of Al2Cu precipitates were found at diamond-Al interface after aging treatment. Moreover, needle-shaped Al2MgCu precipitates in Al matrix were observed after aging treatment. The coefficient of thermal expansion (CTE) of diamond/2024 Al composites was about 8.5×10-6 °C-1 between 20 and 100 °C, which was compatible with that with chip materials. Annealing treatment showed little effect on thermal expansion behavior, and aging treatment could further decrease the CTE of the composites. The thermal conductivity of obtained diamond/2024 Al composites was about 100 W/(m?K), and it was slightly increased after annealing while decreased after aging treatment.