固溶及时效处理对ZL205A合金腐蚀性能的影响  

Effect of solution and aging treatment on corrosion properties of ZL205A alloy

作　　者：郭廷彪[1,2] 冯瑞 王炳 高洋[1] 钱丹晨 丁雨田[1,2] GUO Ting-biao;FENG Rui;WANG Bing;GAO Yang;QIAN Dan-chen;DING Yu-tian(State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals,Lanzhou University of Technology,Lanzhou 730050,China;Key Laboratory of Non-ferrous Metal Alloys and Processing of Ministry of Education,Lanzhou University of Technology,Lanzhou 730050,China)

机构地区：[1]兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室,甘肃兰州730050 [2]兰州理工大学有色金属合金及加工教育部重点实验室,甘肃兰州730050

出　　处：《材料热处理学报》2023年第4期87-94,共8页Transactions of Materials and Heat Treatment

基　　金：甘肃省重点科技研发计划(20YF8GA056);甘肃省重大科技专项(1302GKDA015)。

摘　　要：首先对ZL205A合金进行了固溶及不同温度的时效处理,随后对其进行了NaCl溶液浸泡腐蚀试验和电化学腐蚀试验。采用扫描电镜、透射电镜和能谱仪分析观察了合金热处理后的微观组织和析出相形貌以及腐蚀后的腐蚀形貌和化学成分,分析了合金的腐蚀机理。结果表明:合理的热处理制度能够使合金中析出针状θ相并呈网状分布在晶界上,随着时效温度的升高,析出相粗化并发生团聚,185℃时效后合金中出现了贫Cu区无沉淀析出带(PFZ)。铸态ZL205A合金在NaCl溶液中容易发生点蚀,热处理后点蚀速率大幅度降低,这是因为PFZ和θ相粗化能够显著减弱合金的腐蚀电流密度并阻断点蚀通道,因此提高了ZL205A合金的耐腐蚀性能。双级固溶(530℃×2 h+540℃×13 h)及185℃时效5 h后能够使合金获得优异的耐腐蚀性能。First,ZL205A alloy was treated by solution treatment and aging at different temperatures,and then it was subjected to NaCl solution immersion corrosion test and electrochemical corrosion test.Microstructure and precipitates morphology after heat treatment and corrosion morphology and chemical composition after corrosion test of the alloy were observed and analyzed by scanning electron microscopy,transmission electron microscopy and energy dispersive spectrometer analysis,and the corrosion mechanism of the alloy was analyzed.The results show that the reasonable heat treatment process can make the acicularθphase precipitate in the alloy and distribute at the grain boundary as a network.With the increase of aging temperature,the precipitates coarsen and agglomerate,and the precipitate free zone(PFZ)in the Cu poor zone appears after aging at 185℃.As cast ZL205A alloy is prone to pitting corrosion in NaCl solution,and the pitting corrosion rate decreases significantly after heat treatment,because PFZ andθphase coarsening can significantly reduce the corrosion current density of the alloy and block the pitting channel,thus improving the corrosion resistance of the ZL205A alloy.Two-stage solution treatment(530℃×2 h+540℃×13 h)and aging at 185℃for 5 h can make the alloy obtain excellent corrosion resistance.

关 键 词：ZL205A合金 微观组织 时效处理 腐蚀 

分 类 号：TG146.2[一般工业技术—材料科学与工程]