Microstructural characterization and ablation mechanism of TiB2/(Cu,Ni) melt-infiltrated ceramic composite

In this study TiB2/(Cu,Ni) melt-infiltrated composites with the TiB2 volume content of 81.6% were prepared by mean of pre-sintering of the as-pressed TiB2 preform and melt-infiltration processing. The thermal ablation behavior of TiB2/(Cu,Ni) composite was conducted by plasma arc heater. The microstructure, interfacial bonding and ablation behavior were investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD) pattern. The ablated morphology of cross-section includes three parts: ablated region, transition region and matrix region. The microstructure analysis after ablation experiment reveals a clue of redistribution of infiltrated (Cu,Ni) phase so as to analyze and explain the functioning of transpiration cooling.