涂层硬质合金刀具切削超高强度钢35CrMnSi磨损机理研究

Wear Mechanism of Coated Carbide Insert in Turning of Low Alloy Ultra-High Strength Steel 35CrMnSi

对于低合金超高强度钢35CrMnSi,在分析材料切削特性的基础上,选择涂层硬质合金刀具进行切削试验.改变切削速度,得到使用寿命曲线和t-v曲线,利用扫描电子显微镜(scanning electron microscopy,SEM)和能谱分析仪(energy dispersive spectrometry,EDS)分析研究了磨损区磨损机理.结果表明:使用寿命在切削速度选取范围内随切削速度的增大而明显减小;前刀面上受到氧化及扩散磨损的作用,呈凹坑状的月牙洼磨损,且凹坑随切屑的流动而增大;硬质相的扩散及黏结作用是造成后刀面磨损的主要原因.

Based on the analysis of cutting characteristics of low alloy ultra-high strength steel 35CrMnSi, dry cutting experiments were conducted using coated carbide tools. The relationship of tool life with velocity and cutting time as well as the curve of t-v were achieved. The scanning electron microscopy （SEM） and energy dispersive spectrometry （EDS） were employed to observe morphological features of worn surfaces. The results indicate that the increase of cutting velocity in the selected range leads to the serious decline of the tool life. The rake face shows a pit-shaped crater wear by the effect of oxidation and diffusion wear and the shape of the crater increases with the chip flow-out. The effect of hard phase diffusion and bonding wear are the main cause of flank wear.