Synthesis of Composite Material by Laser Chemical Reaction

本文研究了由石墨粉、硼粉和钛粉混合物制备的碳化硼（B_4C）和硼化钛（TiB_2）复合陶瓷的反应激光烧结。碳化硼是一种硬质材料，因此有望应用于抛光粉。然而，碳化硼具有低韧性，它没有被充分利用。为了提高陶瓷的韧性，研制了碳化硼-硼化钛复合陶瓷。但是，由于这些材料的硬度很高，因此很难对这些材料（碳化硼和硼化钛）进行致密化。由于石墨粉、硼粉和钛粉的混合物硬度不高，采用本方法压制容易。用YAG激光束照射混合物。然后将硼粉铺在碳化钛基体上，YAG激光束在基体上扫描。烧结层用作切削工具。烧结层的刀具寿命与碳化钛刀具相同。

This research work deals with reactive Laser sintering of composite ceramics made of boron carbide (B_4C) and titanium boride (TiB_2) from the mixture of graphite, boron and titanium powder. Boron carbide is a hard material, therefore, it is expected to apply for polishing powder. However, boron carbide has low toughness, it is not used sufficiently. It is developed to produce composite ceramics made of boron carbide and titanium boride in order to improve the toughness of the ceramics. But it is difficult to compact these materials (boron carbide and titanium boride) because the hardness of the materials are very high. The compaction becomes easy by using present method because the hardness of the mixture (graphite, boron and titanium powder) is not high.At first, the conditions to produce the composite ceramics are examined. The mixture is irradiated by the YAG Laser beam. And the produced material is analyzed by X-ray diffraction.Next, boron powder is spread on the titanium carbide substrate, and the YAG Laser beam is scanning on the substrate. The sintered layer is used as a cutting tool. The tool life of the sintered layer is as same as that of the titanium carbide tool.