TiN颗粒增强AgCuTi合金钎焊CBN磨粒的界面微结构

Microstructure of the Interfacial Region between CBN Grains and AgCuTi Alloy Reinforced by TiN Particles

摘要:

向Ag-Cu-Ti合金中加入TiN颗粒组成复合钎料。在加热温度920 ℃和保温时间5 min的工艺下进行立方氮化硼（CBN）磨粒与45#钢基体的连接实验。运用三维视频显微镜、扫描电镜、能谱仪和X射线衍射仪分析TiN颗粒、Ag-Cu-Ti合金、CBN磨粒和钢基体之间的结合界面的微观组织结构。结果表明：加入的TiN颗粒在结合剂层中分布均匀、致密，且显著细化了结合剂层（复合钎料层）显微组织，提高了结合剂层的显微硬度；加入TiN颗粒后仍可确保结合剂层与钢基体之间的良好结合；复合钎料对CBN磨粒有好的润湿性，TiN

Abstract:

The brazing experiments of CBN abrasive grains and the steel with 0.45%C using Ag-Cu-Ti alloy reinforced by TiN particles as composite filler were carried out with heating temperature of 920 ℃ and dwell time of 5 min. The interfacial microstructure and characteristics among TiN particles, Ag-Cu-Ti alloy, CBN grains and the steel substrate were detected with three-dimensional video microscope, scanning electron microscope (SEM), energy dispersion spectrometer (EDS) and X-ray diffraction (XRD). The results show that the microstructure of Ag-Cu-Ti alloy is refined obviously by the well-dispersive TiN particles. The interfacial zone between the particles and the filler is uniformity and compact, and the microhardness of the filler layer is improved. Good combination between the filler and the substrate can still be obtained when the TiN particles are applied. The composite filler doesn’t take negative effects upon the chemical reaction between CBN grains and the filler. Good wetting ability of the composite filler is realized on the CBN grains during brazing, which ensure the hard join to the grains.