YT类硬质合金成形铣刀的金刚石涂层工艺研究

针对YT15硬质合金B212型成形铣刀片,以两种不同的化学方式对硬质合金基体进行预处理,而后采用热丝化学气相沉积的方法在其表面沉积微米级金刚石薄膜.使用扫描电子显微镜观察金刚石薄膜颗粒的大小及均匀度,激光拉曼光谱仪检测金刚石涂层的成分,压痕法检验金刚石涂层刀片的膜-基附着强度,并就不同预处理的基体表面对金刚石薄膜的质量、附着性能的影响进行分析.结果表明,经预处理后的YT类硬质合金表面粗糙度较YG类降低约10%,采用平行布置热丝方式和现有的沉积工艺在YT类硬质合金衬底涂覆的金刚石薄膜均匀性较好,且经酸碱预处理的金刚石薄膜表现出良好的附着力,附着强度介于600~1 000 N,醇碱预处理对衬底表面原有的光洁度损坏较小,有助于细化金刚石晶粒,但膜-基附着强度不高.

Research on diamond films coating process for YT carbide shaped milling tools

For the YT15 carbide shaped milling cutter blade of B212 type,micron diamond films are deposited by the method of two kinds of different chemical pretreatments on cemented carbide substrate before hot filament chemical vapor deposition.A scanning electron microscope is adopted to observe the size and uniformity of diamond film particles; a laser Raman spectroscopy is employed to detect diamond films coating composition; the indentation method is utilized to test the adhesion strength between films and substrate.Besides,the impact of the substrate suifaee under different pretreatments on the quality and adhesion of diamond films is analyzed.Results show that after pretreatment,the YT carbide surface roughness is reduced about 10％,compared with the YG carbide,and that the uniformity of diamond films deposited on the YT carbide substrate is better under the parallel hot filaments arrangement in a conventional deposition process.Diamond films exhibit good adhesion by the acid-alkali pretreatment with the adhesion strength between 600 N and 1 000 N.The alcohol-alkali pretreatment on the substrate destroys the original surfaee finish less and helps refine the diamond grains,but the adhesion strength is lower between films and substrate.