金属结合剂金刚石砂轮中铝基结合剂性能优化研究

以AlSi₂₀为主元,选择强化铝的常用合金元素Cu、Zn、Mg、Mn等4因素（分别用A、B、C、D表示）,每个因素各取3个水平,制定了L₉（34）正交试验方案。采用热压烧结制备铝基结合剂胎体。通过阿基米德排水法、硬度测试、三点弯曲强度测试、扫描电镜观察断口形貌等方法,研究合金元素对铝基结合剂性能的影响。实验结果表明:添加的合金元素降低AlSi₂₀的烧结温度,促进烧结致密化;合金元素对硬度的影响大小顺序为Mn>Zn>Cu>Mg,对抗弯强度的影响大小顺序为Cu>Mn>Zn>Mg;组合A₁B₂C₂D₂、A₁B₃C₃D₃有高的硬度和抗弯强度,胎体对金刚石包镶紧密;结合剂断裂方式为脆性断裂,可以提高金刚石砂轮的自锐性。 

Performance optimization of Al-based bond matrix in metallic bond diamond wheel

Commonly used alloying elements, namely Cu, Zn, Mg and Mn, were selected to strengthen aluminum with AlSi₂₀ as the main component. The factors, each with three levels, were marked as A, B, C and D, respectively. The L₉(34) orthogonal test scheme was developed. Al-based bonding matrix was prepared by hot pressing sintering. The effects of alloying elements on the properties of the matrix were studied by means of Archimedes drainage method, rockwell hardness test, three-point bending strength test and scanning electron microscope. Results show that the addition of alloy elements reduces the sintering temperature of AlSi₂₀ and promotes the densification of sintering. The influence of alloy elements on hardness is Mn>Zn>Cu>Mg. The influence of bending strength is Cu>Mn>Zn>Mg. In conclusion, the combination of A₁B₂C₂D₂ and A₁B₃C₃D₃ have high hardness and bending strength, whose matrices are closely tied to diamond. The fracture mode of binding agent is brittle fracture, which can improve the self-dressing ability of diamond grinding wheel.