高频电源与活性屏离子渗氮对表面纳米化TC4钛合金渗氮层结合力的影响  

Effect of High Frequency Power Supply and Active Screen Plasma Nitriding on the Adhesion of Surface Nano-sized TC4 Titanium Alloy Nitriding Layer

作　　者：高鸿 文凯 张乘玮 高岩[1] GAO Hong;WEN Kai;ZHANG Chengwei;GAO Yan(School of Materials Science and Engineering,South China University of Technology,Guangzhou 510641,China)

机构地区：[1]华南理工大学材料科学与工程学院,广州510641

出　　处：《表面技术》2024年第17期157-169,共13页Surface Technology

基　　金：国家自然科学基金项目(51871099)。

摘　　要：目的 评估高频电源对喷丸纳米化TC4钛合金离子渗氮层结合力的影响,进一步探究在高频电源+活性屏工艺组合上,渗氮参数优化对渗氮层结合力的影响。方法 选取直流电源–500℃-20 h-300 Pa离子渗氮试样与高频电源–500℃-20 h-200 Pa离子渗氮试样,分别进行XRD、扫描电镜和划痕试验,对结构、形貌与结合力分析。在高频电源基础上,进一步选取活性屏优化前、后参数的渗氮试样进行结构、形貌和结合力对比。结果 通过划痕测试发现,高频电源渗氮层的声信号平稳,划痕无剥落,渗氮层摩擦力信号突增的载荷值有一定提升。在高频电源+活性屏工艺组合下,优化后渗氮试样的Ti N和Ti2N层厚度比优化前渗氮试样的厚度明显增加。声信号上表现为更平稳及无明显突变,且优化后试样的渗氮层摩擦力信号突增的载荷值较优化前均增加。结论 高频电源抑制了传统直流电源渗氮过程中的打弧现象,缓解了渗氮层内部的热应力聚集,提高了渗氮层的表面性能,对渗氮层载荷承受力和结合力有一定的提升作用。在高频电源与活性屏组合工艺下,优化后渗氮试样的渗氮动力学条件更好,Ti2N层厚度显著增加,提高了基体中氮扩散层的性能。同时,Ti2N厚度的增加可以减缓TiN层与基体的成分与性能的突变,从而提升渗氮层与基体的结合力。High frequency power supply and active screen technology can alleviate the negative factors such as arc striking,edge effect and hollow cathode effect during traditional direct current(DC)power supply nitriding,but the evaluation of adhesion needs to be studied.The work aims to evaluate the effect of high frequency power supply on the adhesion of surface shot peening nano TC4 titanium alloy nitriding layer,and further explore the effect of nitriding parameter optimization on the adhesion of nitriding layer based on the combination of high frequency power supply and active screen technology.Based on the optimization results of the high frequency power supply and active screen parameters in the early stage of the research group,samples of DC power supply under-500℃-20 h-300 Pa nitriding and high frequency power supply under-500℃-20 h-200 Pa nitriding with similar nitriding layer thickness(to eliminate the effect of thickness difference on the adhesion of the nitriding layer)were selected to analyze the structure,morphology and adhesion respectively by X-ray diffraction(XRD),scanning electron microscopy(SEM)and scratch experiments.On the basis of high frequency power supply,the optimized parameters of the active screen(high frequency power supply under-500℃-20 h-200 Pa-400 V bias voltages)and the nitrided samples before the optimization of the active screen(high frequency power supply under-500℃-20 h-300 Pa-1100 V bias voltages)were selected to compare structure,morphology,and adhesion.According to the scratch adhesion test results,the acoustic signal of the high frequency power supply nitriding layer was stable,and the scratches did not peel off.The load values(5.1 N and 5.2 N)of the frictional force signal of the nitriding layer in the original nitriding sample and the shot peening nitriding sample increased sharply compared to the load values of the nitriding sample corresponding to the DC power supply(starting from the initial loading).Under the combination of high frequency power supply and active scree

关 键 词：TC4钛合金 活性屏离子渗氮 高频电源 表面纳米化 结合力 

分 类 号：TG174.4[金属学及工艺—金属表面处理]