【摘要】 研究大功率激光器焊接TiB2颗粒增强铝基复合材料时TiB2粒子的演变行为。采用X射线衍射(XRD)、扫描电镜(SEM)及能谱(EDS)分析焊缝内粒子的物相、热力学过程及形貌特征;同时对TiB2和铝基体的界面反应进行讨论。结果表明:当TiB2团簇尺寸大于激光光斑直径时,焊缝中部的TiB2粒子会熔融在一起,较大尺寸的TiB2会发生断裂;当与铝熔体接触后,熔化后的TiB2粒子会与Al发生反应生成Al3Ti和AlB12,并且焊缝中部的界面反应比焊缝边缘的剧烈。更多还原

【Abstract】 The evolution behavior of TiB2 particles was studied during laser welding on aluminum metal matrix composites (MMCs) reinforced with TiB2 particles by a high power laser.X-ray diffractometry (XRD), scanning electron microscopy (SEM) and energy spectrum analysis (EDS) were used to analyze the phase, thermodynamics and morphology characteristics of the particles in the weld seam, and the interface reactions between TiB2 particles and aluminum matrix were also discussed.The results show that partial TiB2 particles melt and merge into larger ones in the middle of the weld seam and that fracture can be found in larger particles when the scale of TiB2 cluster is larger than the spot size of laser.Al3Ti and AlB12 are produced by the interface reaction between TiB2 particles and Al matrix.The interface reaction of broken TiB2 particles in the middle of the weld seam is stronger than that at the edge of the weld seam.更多还原