高速铣削蠕墨铸铁的切屑形成及表面质量研究  

Study on Chip Formation and Surface Quality of High-speed Milling Compacted Graphite Iron

作　　者：熊飞翔 杨碧涛 胡珊珊[1] 林勇传[4] 王成勇[3] Xiong Feixiang;Yang Bitao;Hu Shanshan;Lin Yongchuan;Wang Chengyong

机构地区：[1]广西大学机械工程学院,南宁市530004 [2]云南红河技师学院 [3]广东工业大学 [4]广西大学

出　　处：《工具技术》2020年第1期9-15,共7页Tool Engineering

基　　金：国家自然科学基金(51565005);广西有色金属加工特种材料重点试验室资助项目(GXKFJ16-16)

摘　　要：蠕墨铸铁(Compacted Graphite Iron)因具有优异的综合力学性能而被广泛应用于汽车和机车行业。由于蠕墨铸铁的可加工性较差,在加工过程中仍然存在许多问题。本文通过单因素试验法,在不同切削速度/进给速度的组合下进行铣削试验,揭示了高速铣削蠕墨铸铁(RuT400)的切屑形成和工艺参数对表面质量的影响。通过测量铣削力和表面粗糙度,用最小二乘法建立工艺参数与铣削力和表面粗糙度之间的拟合方程,并从宏观和微观的角度观察切屑的形成。结果表明,拟合方程的铣削力和表面粗糙度与试验数据吻合度较高,可为铣削力和表面粗糙度预测提供参考。通过扫描电子显微镜(SEM)观察低切削速度和进给速率下产生的长卷型切屑,发现所有切屑均呈“C”形弯曲形状。切屑厚度和锯齿间距与进给速率的增加呈负相关,与切削速度的增加呈正相关。通过计算蠕墨铸铁的临界冲击速度并加以修正,得到了崩碎状切屑出现的实际临界冲击速度,为工艺参数优化和切屑形态变化预测提供了理论基础。Compacted graphite iron(CGI)with excellent comprehensive mechanical properties is widely used in automotive and locomotive industries.However,many problems still remains in machining CGI due to its poor machinability.By means of single-factor milling experiment with different cutting speed/feed rate combinations,the influence of chip formation and cutting parameters on surface quality when milling CGI(RuT400)at high speed is revealed.Through measuring the cutting force and surface roughness,the fitted equations describing the relationship between the cutting parameters and the cutting force and surface roughness are established,and the chips are observed from macro and micro views.It is found that the cutting force and surface roughness from the fitted equations are similar to those from experiments,thus the fitted equation could be used to predict the cutting force and surface roughness.At low cutting speed and feed rate and observed by SEM,it is found that all chips are long-curling with C-shape.The thickness of the chip and the sawtooth pitch show some negative correlation with the increasing of feed rate,and some positive correlation with the increasing of cutting speed.

关 键 词：蠕墨铸铁 切屑形成 表面粗糙度 高速铣削 

分 类 号：TG501[金属学及工艺—金属切削加工及机床] TG506.1