喷砂钝化对硬质合金数控刀片腐蚀行为的影响研究  

Research on Effect of Sandblast on Corrosion Behavior of Cemented Carbide Cutting Tools

作　　者：甘信峰 易慧 于涛 Gan Xinfeng;Yi Hui;Yu Tao(Nanchang Cemented Carbide Limited Liability Company)

机构地区：[1]南昌硬质合金有限责任公司 [2]株洲钻石切削刀具股份有限公司

出　　处：《工具技术》2023年第8期53-58,共6页Tool Engineering

摘　　要：针对硬质合金数控刀片刃口制备工艺,采用喷砂钝化取代传统的毛刷钝化后,表面微观组织发生显著变化,可能会导致合金生产制备过程中腐蚀行为的变化。系统研究了在自来水、NaHCO_(3)溶液和酒石酸溶液中喷砂钝化对合金腐蚀行为的影响,研究结果显示:喷砂钝化显著提高了合金在自来水、NaHCO_(3)溶液和酒石酸溶液中的抗腐蚀能力,WC和Co相在不同的腐蚀介质中显示出不同的腐蚀行为,在中性和碱性溶液中以Co的氧化为主(碱性溶液中伴随着W的溶解),在酸性溶液中以Co的溶解为主。合金腐蚀性能的提高主要是由于喷砂钝化过程中基体表面WC颗粒破碎,较小WC颗粒填充在大WC颗粒之间,并被Co相包裹,有效降低了发生缝隙腐蚀的概率。此外,喷砂钝化过程中表面极易形成致密的CoO钝化膜,有效避免了Co相与WC颗粒进一步被腐蚀。Traditional brush edge preparation is replaced by sandblast edge preparation in cemented carbide cutting tools fields,which can play a significant role on the microstructure of the surface and corrosion behavior of the alloy.The effect of sandblast on the alloy corrosion is systematically investigated by immersing in the water,NaHCO_(3)solution and tartaric acid for different time duration.The results show that the corrosion resistance is greatly improved in all of the above electrolyte.The WC and Co display as different corrosion behavior in different corrosion medium.In the netrual and akline solution,corrosion mainly display as oxidation of Co,and accompanied by dissolvation of W in alkine solution.In acid solution,the alloy corrosion is mainly controlled by the dissolvation of Co.Due to the crushed WC particles buried between the big ones and capsuled by Co,the enhancement of corrosion resistant by sandblast is greatly reduced the frequency of crevice corrosion of the alloy.A compact passivation film can be easily formed during sandblast and effectively protect the corrosion of Co and WC.

关 键 词：数控刀片 刃口制备 喷砂 腐蚀 

分 类 号：TG71[金属学及工艺—刀具与模具] TH161[机械工程—机械制造及自动化]