高级检索

电流密度对刀具上喷射电沉积CoNiCrC涂层组织及摩擦性能的影响

Effect of Current Density on Microstructure and Frictional Properties of CoNiCrC Coatings on Cutting Tools

  • 摘要: 以Cr3C2颗粒作为增强体,通过喷射电沉积的方法在刀具上制备得到CoNiCrC涂层。对比了不同电流密度下的Cr3C2颗粒沉积量,并对CoNiCrC涂层微观组织结构、硬度、元素含量、耐磨能力进行了测试。研究结果表明:随着电流密度的提高,Co含量减小,Cr3C2比例先升高再减小,40 A/dm2时颗粒含量提高至12.1%。涂层跟基体间达到了良好结合状态,生成了致密的组织结构。此时在涂层内形成了密排六方结构的Co晶体与Cr3C2相,电流密度提高并未对涂层物相相结构产生影响。逐渐增大电流密度,CoNiCrC涂层发生了硬度先上升再下降。当电流密度40 A/dm2时,涂层硬度增大至586 HV。提高电流密度后,涂层发生了磨损体积先降低再增大。当电流密度为40 A/dm2时,涂层达到了最低磨损体积。涂层内添加Cr3C2颗粒获得了更强弥散增强作用,能够更好地抵抗摩擦作用。

     

    Abstract: The CoNiCrC coating was prepared by jet electrodeposition on the cutting tool with Cr3C2 particles as the reinforcement.The deposition amount of Cr3C2 particles under different current densities was compared, and the microstructure, hardness, element content, and wear resistance of CoNiCrC coating were tested.The results show that with the increase of current density, Co content decreases, Cr3C2 ratio first increases and then decreases, and particle content increases to 12.1% at 40 A/dm2.The coating and substrate are in good bonding state, and a compact structure is formed.At this time, Co crystal with dense hexagonal structure and Cr3C2 phase are formed in the coating, and the increase of current density does not affect the phase structure of the coating.With increasing current density, the hardness of CoNiCrC coating first increases and then decreases.When the current density is 40 A/dm2,the coating hardness increases to 586 HV.After increasing the current density, the wear volume of the coating first decreases and then increases.The coating reaches a minimum wear volume at a current density of 40 A/dm2.The addition of Cr3C2 particles in the coating results in stronger dispersion enhancement and better resistance to friction.

     

/

返回文章
返回