包埋深度的确定
(南京航空航天大学 机电学院，南京 210016)
摘 要: 以Ag-Cu-Ti合金为钎料在真空炉中实现了CBN磨粒与45钢基体的钎焊连接，运用红外光谱仪测试了钎焊磨粒内部的残余应力，分析了最大残余拉应力对磨粒强度的影响，据此优选了钎焊CBN砂轮工作面上磨粒的包埋深度。结果表明：当包埋深度不同时，尽管钎焊磨粒内部的残余应力分布差异较大，但最大残余拉应力始终位于磨粒与钎料顶层截面的边缘位置，并且最大残余拉应力与包埋深度不存在线性关系；为提高钎焊CBN磨粒强度和确保砂轮容屑空间，磨粒包埋深度应控制在其自身高度的30%~40%之间。
关键字: CBN磨粒；钎料层；单层钎焊砂轮；包埋深度；残余应力
on working surface of single-layer brazed CBN grinding wheel
（College of Mechanical and Electrical Engineering,
Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China）
Abstract:The joining of CBN abrasive grain and 0.45%C steel matrix was realized using Ag-Cu-Ti alloy as filler metal in the vacuum furnace. The residual stresses of the brazed CBN grains were measured by means of FTIR spectra. The influence of the maximum tensile stress on the grain strength was analyzed, and the embedding depth of grains on the working surface of the brazed single-layer grinding wheels was accordingly determined. The result shows that, though remarkable difference of stress distribution occurs in the brazed grains with different embedding depths, the maximum tensile stress always exists in the margin region of the section plane between CBN grain and filler top. Moreover, the maximum tensile stress is not influenced linearly by the embedding depth. In order to ensure the strength of the brazed grains and the enough space for holding chips, 30%−40% of the whole height of abrasive grain is the rational embedding depth for CBN grains.
Key words: CBN abrasive grain; filler metal layer; singer-layer brazed grinding wheel; embedding depth; residual stress
