(1. 南京航空航天大學(xué) 材料科學(xué)與技術(shù)學(xué)院，南京 211106；
2. 江蘇麟龍新材料股份有限公司，無錫 214100)
摘 要: 對(duì)電弧噴涂Zn-Al-Si合金涂層進(jìn)行熱等靜壓(HIP)處理，通過電化學(xué)測(cè)試、鹽水(3.5%NaCl，質(zhì)量分?jǐn)?shù))全浸實(shí)驗(yàn)、掃描電鏡觀察和能譜分析，研究熱等靜壓處理對(duì)電弧噴涂Zn-Al-Si合金涂層耐蝕性能的影響。結(jié)果表明：300 ℃、1 h、150 MPa HIP處理能大幅降低電弧噴涂Zn-Al-Si合金涂層的腐蝕電流，促進(jìn)鈍化現(xiàn)象的產(chǎn)生，提高耐腐蝕性能和防護(hù)壽命。HIP處理改善了涂層表面不平整結(jié)構(gòu)、促進(jìn)了表面元素分布；基本消除了涂層孔隙結(jié)構(gòu)，孔隙率降低了87.15%，避免閉塞電池腐蝕的發(fā)生和涂層內(nèi)部孔隙拓展延伸。經(jīng)HIP處理后，涂層元素的均勻分布、平整的表面結(jié)構(gòu)和致密的內(nèi)部組織是降低腐蝕電流及產(chǎn)生鈍化現(xiàn)象的主要原因。
關(guān)鍵字: Zn-Al-Si合金；熱等靜壓；孔隙率；耐腐蝕性
（1. Nanjing University of Aeronautics and Astronautics, Nanjing 211106, China;
2. Jiangsu Linlong New Materials Co. Ltd., Wuxi 214100, China）
Abstract:The influence of hot isostatic pressing (HIP) on the corrosion resistance of arc spraying Zn-Al-Si alloy coating was studied by electrochemical test, salt solution (3.5%NaCl, mass fraction) immersion test, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The results indicate that when the alloy is HIP-processed at 150 MPa and 300 ℃ for 1 h, the corrosion current of arc spraying Zn-Al-Si coating is greatly reduced, the passivation phenomenon is promoted, and the corrosion resistance and protective life are improved. HIP treatment flats the surface, improves the element distribution, greatly eliminates the pore structure. The porosity is decreased by 87.15%, occluded cell corrosion and pore extension are avoided. Uniform element distribution, flat surface structure and dense internal tissue are the main reasons to cause the reduction of corrosion current and passivation phenomenon.
Key words: Zn-Al-Si alloy; hot isostatic pressing; porosity; corrosion resistance
