高能磁磨加工技术对铜铬触头材料表面质量的影响

Influence of High Energy Magnetic Grinding Technology on Surface Quality of Cu-Cr Contact Materials

利用磁力研磨抛光法,以NC-803极压精密切屑油为研磨介质,SUS304磁化组合钢针为磨料,选择真空熔铸法CuCr(30)机加工成型触头为研究材料并进行研磨处理,采用单因素及正交试验法优化研磨工艺。探究研磨频率、交换时间、研磨时间、磨料比重等因素对CuCr(30)触头表面粗糙度的影响。结果表明:以NC-803极压精密切屑油为研磨介质,SUS304磁化组合钢针为磨料时,最佳磁力研磨工艺为研磨频率50 Hz、交换时间3 min、研磨时间60 min、磨料比重15%。在此条件下,CuCr(30)触头材料表面粗糙度变化ΔRa平均值达0.534μm。通过外观、投影尺寸和金相等对CuCr(30)触头材料表面观察分析,研磨后触头的表面粗糙度明显降低,表面质量得到了改善,验证了采用磁力研磨抛光法对CuCr合金触头材料进行光整加工的可行性和可靠性。

With NC-803 extreme pressure fine abrasive oil as grinding medium,SUS304 magnetized composite steel needle as abrasive,and CuCr(30)contact machined by vacuum casting method as research material,the grinding process was optimized by single factor and orthogonal experiment.The effects of grinding frequency,exchange time,grinding time and specific gravity of abrasive on the surface roughness of CuCr(30)contact were investigated.The results show that the best magnetic grinding process is grinding frequency 50 Hz,exchange time 3 min,grinding time 60 min and specific gravity 15%when NC-803 extreme pressure fine abrasive oil is used as grinding medium and SUS304 magnetized steel needle is used as abrasive.Under these conditions,the average variation ra of surface roughness of CuCr(30)contact material is 0.534μm.By observing and analyzing the surface of CuCr(30)contact material in terms of appearance,projection size and gold,the surface roughness of the contact is obviously reduced and the surface quality is improved after grinding,which verifies the feasibility and reliability of finishing CuCr alloy contact material by magnetic grinding and polishing.