Reactive YAG Laser Sintering of Gradient Functional Film Made of Hard Boron Carbide

本文研究了在石墨和硼粉混合物的衬底上反应激光烧结碳化硼(B4C)。碳化硼(B_4C)是一种硬质材料，有望用作抛光粉，但烧结困难，材料未得到充分利用。本工作希望通过激光加热碳化硼与基片之间的结合，从而产生梯度功能薄膜。首先，用激光照射石墨和硼粉的混合物。用X射线衍射仪对烧结体进行了分析。用这种方法合成了碳化硼(B_4C)。接下来，将混合物扩散到基板上，并在基板上扫描YAG激光束。碳化硼薄膜的硬度为16 Gpa。最后，将该方法应用于高深宽比碳化硼微细零件的制造。通过其他陶瓷材料的复合，薄膜的硬度有望得到提高。

This research work deals with reactive Laser sintering of boron carbide (B_4C) on a substrate from mixture of graphite and boron powder. The boron carbide (B_4C) is a hard material, therefore, it is expected to apply for polishing powder However, it is difficult to sinter, the material is not used sufficiently. It is expected to become adhesion between the boron carbide and the substrate and expected to produce gradient functional film by the heat of the Laser on the present work.At first, the mixture of the graphite and boron powder is irradiated by the YAG Laser beam. And the sintered material is analyzed by X-ray diffraction. Boron carbide (B_4C) is composed by this method. Next, the mixture is spread on the substrate, and the YAG Laser beam is scanning on the substrate. The hardness of the boron carbide film is 16 GPa. At last, this method is applied for the producing high aspect ratio micro parts made of boron carbide. The hardness of the film is expected to increase by composing by other ceramics.