用感应加热摩擦法在屏蔽金刚石表面涂覆Ti涂层

Fabrication of Ti layer on The Shielded Diamond Surface with Induction Heating Friction Method

摘要:

提出一种在金刚石表面制备Ti涂层的新方法，将感应加热到一定温度的Ti棒，在电磁屏蔽保护下的聚晶金刚石表面以旋转挤压的方式进行摩擦涂覆，实现了金刚石表面的金属化。通过红外测温仪测试聚晶金刚石表面温度，利用扫描电子显微镜观察Ti涂层的界面形貌、内表面形貌以及聚晶金刚石/硬质合金之间的界面形貌，采用X射线衍射仪检测Ti涂层内表面物相组成，通过能谱分析仪对Ti涂层界面和内表面进行元素分析。研究结果发现:高温Ti棒与聚晶金刚石表面进行摩擦涂覆，在聚晶金刚石与Ti涂层界面处发生了C、Ti元素的相互扩散，且在界面处产生有点状碳化物TiC。将聚晶金刚石置于具有电磁屏蔽的装置中，可有效避免聚晶金刚石/硬质合金界面处的热损伤。Ti涂层的形成过程可分为三个阶段:新鲜表面相互接触、初始扩散、扩散带形成。本文提出的感应加热摩擦法工艺简便，能够显著提高涂覆效率，可以有效避免金刚石热损伤。

Abstract:

A new method of fabricating Ti layer on diamond surface was proposed to obtain the metallization of diamond surface. A Ti bar heated to a certain temperature with induction method was rotated, extruded and rubbed on the surface of shielded polycrystalline diamond. The surface temperature of polycrystalline diamond was measured with infrared thermometer. The interface and inner surface of Ti layer, and the interface between polycrystalline diamond and cemented carbide were observed with scanning electron microscope. The phase composition of the inner surface, the elements of the interface and inner surface of Ti layer were analyzed with X-ray diffractometer and energy spectrum analyzer, respectively. The research results show that the mutual diffusion of C and Ti elements occurs at the interface between polycrystalline diamond and Ti layer, and TiC with spot shape is generated. The chemical bonding between polycrystalline diamond and Ti layer can be realized. Thermal damage at the interface between polycrystalline diamond and the cemented carbide can be effectively avoided by placing polycrystalline diamond in an electromagnetic shielding device. The formation process of Ti layer on diamond surface can be divided into three stages: contact of fresh surfaces, initial diffusion and formation of diffusion band. The proposed method has features of fabricating processes simply, increasing layer efficiency significantly and avoiding diamond thermal damage effectively.