摘要
目的研究热输入对TC4钛合金微弧氧化膜层性能的影响,控制微弧氧化过程中的能量消耗。方法在TC4钛合金表面制备微弧氧化膜层时,通过改变热输入来形成不同的热效应,采用扫描电镜、能谱仪、X射线衍射仪分析在不同热输入下所制备膜层的表面形貌、截面形貌、元素分布和相组成,测试热输入对TC4钛合金微弧氧化膜层耐磨性和耐蚀性的影响。结果热输入影响了膜层生成过程中的离子传输,提高了膜层中Ti原子与O原子的比值,有利于TiO_(2)膜层的生成,但过高的热输入会使参与反应的Ti、O原子减少,从而降低膜层的生长速率。膜层的厚度随着热输入的增大先由18.53μm增加至21.56μm,随后减小至17.67μm,膜层主要相的组成为Rutile、Anatase及少量SiO_(2)。通过改变热输入提高了膜层的耐腐蚀性能,其腐蚀速率从4.516×10^(-3) mm/a逐渐减小至3.109×10^(-4) mm/a。膜层表面的耐磨性能随着热输入的增大呈先增加后降低的趋势。结论当热输入为140 W时,膜层的厚度最高,耐磨性能最佳,同时具备良好的耐腐蚀性能。
Micro-arc oxidation technology is an environmentally friendly surface modification technology,which improves the surface properties such as wear resistance,corrosion resistance,thermal shock resistance,hardness and other properties by in-situ synthesis of functional ceramic coatings on the valve metal surface.Some scholars have found that during the micro-arc oxidation process,a large amount of heat is released,the temperature of the electrolyte increases rapidly,which seriously affects the corrosion resistance and wear resistance of the coating.The work aims to study the effects of heat input on the characteristics of the micro-arc oxidation coating of TC4 titanium alloy by adjusting the heater power so as to provide a theoretical basis for improving the refrigeration system in micro-arc oxidation.The TC4 titanium alloy was cut into a rectangle of 15 mm×15 mm×2 mm as the base material and polished and with 400#,800#,1200#,2000#sandpaper in turn.The test adopted pulse power supplies(DWL20-6),the output mode adopted constant current,the current density was 5.2 A/dm^(2),the frequency was 100 Hz,the duty cycle was 40%,and the time was 15 min.The electrolyte composition was Na2SiO_(3)(12 g/L),(NaPO_(3))66 g/L,Na2WO41.5 g/L,NaOH 0.5 g/L,C3H8O_(3)3 mL/L,EDTA 0.3 g/L,C6H15NO_(3)1 mL/L.Before the test,the initial temperature was controlled to 20℃by the cool system,the constant heat input during the micro-arc oxidation process was controlled to 0,70,140,210,280 W respectively.The surface morphology,cross-sectional morphology and elements of the coatings were analyzed by scanning electron microscopy(ZEISS EVO MA15)and X-ray energy dispersive spectrometer(OXFORD X-max).The phase composition of the coatings was analyzed by X-ray diffractometer(DX-2700B).The microhardness of the coating was measured by a digital microhardness tester(HXD2000TM/LCD,China).The polarization curves of the solution samples against 3.5wt.%NaCl solution were measured using an electrochemical workstation(Gamry Reference 3000,USA).Reciprocating fri
作者
龚云柏
王平
杨彪
伍婷
杨钊
段艳菲
兰欣悦
GONG Yun-bai;WANG Ping;YANG Biao;WU Ting;YANG Zhao;DUAN Yan-fei;LAN Xin-yue(School of New Energy and Materials,Southwest Petroleum University,Chengdu 610500,China;Institute of Surface Science,Helmhotz-Zentrum Hereon,Geesthacht 21502,Germany)
出处
《表面技术》
EI
CAS
CSCD
北大核心
2022年第12期159-168,共10页
Surface Technology
基金
四川省科技计划(2022YFSY0018)。
关键词
TC4钛合金
微弧氧化
热输入
微观结构
耐腐蚀性
耐磨性
TC4 titaninum alloy
micro-arc oxidation
heat input
microstructure
corrosion resistance
wear resistance
