高速切削高碳当量合金灰铸铁制动盘的PCBN刀具磨损分析与工艺改进  

Wear and Breakage Analysis of PCBN Tool During High-speed Machining of High-carbon Equivalent Grey Cast Iron Brake Discs and Process Improvement

作　　者：陈荣发[1] 史敏杰 王锴 赵毅红[1] 郑志伟 翟旭军[3] 李芳芳 叶成聪 Chen Rongfa;Shi Minjie;Wang Kai;Zhao Yihong;Zheng Zhiwei;Zhai Xujun;Li Fangfang;Ye Chengcong(不详;School of Mechanical Engineering,Yangzhou University,Yangzhou,Jiangsu 225009,China)

机构地区：[1]扬州大学机械工程学院,江苏省扬州市225009 [2]通富热处理(昆山)有限公司 [3]江苏农牧科技职业学院

出　　处：《工具技术》2023年第6期23-28,共6页Tool Engineering

基　　金：国家自然科学基金(51872254);扬州市校合作专项(YZ2021151,YZ2021155)。

摘　　要：采用PCBN刀具对高碳当量合金灰铸铁进行高速切削实验,通过IM3000光学显微镜、LSM7003D测量激光显微镜、S-4800Ⅱ场发射扫描电镜对产生崩裂破损的刀具进行观察与分析。结果表明:高速切削后PCBN刀具表面同时存在磨粒磨损、黏结磨损和氧化磨损三种磨损形式;高速切削加工含有过多高塑、韧性游离铁素体的制动盘时,刀具前、后刀面黏结物均有增多,导致刀具表面出现严重的黏结磨损,并且伴有大面积切削刃崩刃;恶化的切削条件使得刀具表面过早出现磨损与裂纹,从而在切削时引起刀具振动,最终导致PCBN刀具崩裂破损。为了改善切削加工条件,通过改进刹车盘的铸造工艺减少铁素体数量,改进后的制动盘铸态组织以珠光体为主,有效减少了刀具的崩刃概率,提高了生产效率。High-speed cutting experiment is carried out on high-carbon-equivalent gray cast iron(HCEGCI)with PCBN tools.The broken tools are observed and analyzed by optical microscope,laser microscope,and scanning electron microscope.The results indicate that there are three types of wear on the tool surface after high-speed cutting,which are abrasive wear,adhesive wear and oxidative wear.When cutting the workpieces containing too much high-plastic and tough ferrite,the adhesions on the rake face and flank face increase,resulting in severe adhesive wear on tool surface and large chipping of the cutting edge.Deteriorated cutting conditions cause premature wear and cracks on tool surface,which cause vibration during cutting and eventually leads to tool breakage.In order to improve the cutting conditions,the casting process of the brake disc is improved,the quantity of ferrite is reduced,and the as-cast structure of the obtained brake disc is mainly pearlite,which effectively reduces the probability of tool breakage and improves the production efficiency.

关 键 词：高速切削 PCBN刀具 灰铸铁 磨损机理 失效分析 

分 类 号：TG71[金属学及工艺—刀具与模具] TH142[一般工业技术—材料科学与工程]