(1. 成都工具研究所 涂层中心， 成都 610051;
2.四川大学 金属材料系， 成都 610065)
摘 要: 利用X射线衍射研究了CP3型硬质合金涂覆5层(TiC -TiNC-TiC-TiCN-TiN)硬质层的组织，用扫描电镜观察了涂层的断口形貌，用划痕法测定了涂层与基体的结合力，用三点弯曲方法测定了涂覆前后硬质合金的抗弯强度，并用Weibull统计方法对其进行了分析。结 果表明：涂层组织由TiC，TiC0.2N0.8和TiN组成，涂层中无发达的柱状晶，涂层与基体结合良好，涂覆后硬质合金的抗弯强度有所下降，但分散性却减小。
关键字: 硬质合金；CVD；结构；抗弯强度；分散性
WC-based hard metal coating
by CVD
（1.The Center of Coating, Chengdu Tool Institute,
Chengdu 610051, China;
2.Department of Metal Materials, Sichuan University,
Chengdu 610065, China）
Abstract:The microstructures of a cemented carbide with five coated layers by CVD were investigated using XRD. Bonding force between coating and base was measured by scratching. Three-point bending strength was surveyed and its scatter was analyzed by Weibull statistic. Results show that the coating consists of TiC，TiC0.2N0.8 and TiN，there is no developed column crystal in there， bonding between coating and base is very nice，after coating bending strength of the hard metal decreases but its scatter becomes smaller.
Key words: cemented carbide; CVD; coating structure; bending strength; scatter
