郭小華, 趙 亮
(湖南大學(xué) 化學(xué)化工學(xué)院, 長(zhǎng)沙 410082)
摘 要: 介紹了Mg合金的腐蝕原理、 腐蝕類型以及合金元素在鎂合金中的作用。 綜述了Mg合金的化學(xué)轉(zhuǎn)化膜、 陽(yáng)極氧化、 微弧氧化、 化學(xué)鍍等經(jīng)典的表面處理方法, 以及快速凝固工藝和表面改性技術(shù)對(duì)Mg合金表面耐蝕性能的影響。 Mg合金易發(fā)生全面腐蝕、 電偶腐蝕、 點(diǎn)蝕、應(yīng)力腐蝕和高溫氧化。 解決Mg合金腐蝕的方法有: 一是研究新合金, 提高M(jìn)g合金自身的熱力學(xué)穩(wěn)定性,稀土Mg合金是最有前途的耐蝕合金; 二是通過表面處理使Mg合金表面富SiO2和Al2O3、含SiC和F-等物質(zhì)或獲得的非晶態(tài)的涂層結(jié)構(gòu)能有效地提高M(jìn)g合金的耐蝕耐磨性能; 三是改進(jìn)加工工藝, 快速凝固和激光退火不僅能獲得力學(xué)性能優(yōu)秀的Mg合金產(chǎn)品,還能獲得納米結(jié)構(gòu)的表面涂層防護(hù)膜, 提高M(jìn)g合金的耐蝕耐磨性能。 使鎂合金表面涂層結(jié)構(gòu)納米化、 玻璃化是表面處理工藝的發(fā)展趨勢(shì)。
關(guān)鍵字: Mg合金; 腐蝕; 表面處理; 防護(hù)設(shè)計(jì)
GUO Xiao-hua, ZHAO Liang
(College of Chemistry and Chemical Engineering, Hunan University,
Changsha 410082, China)
Abstract:Corrosion principle, corrosion types and effects of alloying elements in Mg alloys are introduced. The conventional processes of chemical conversion film, anode oxidation, micro-arch oxidation and electroless plating, and effect of rapid solidification as well as surface modification on corrosion resistance of magnesium alloys are reviewed. Mg alloys are apt to suffer from general, galvanic, pitting, SCC and high temperature oxidation. Approaches toward overcoming corrosion problems are: 1) developing new alloys to increase their thermodynamic stability, RE alloys are promising in resistance to high temperature oxidation; 2) the treatment surface of SiO2, Al2O3 rich coatings and containing SiC, F-or amorphous coatings to improve the corrosion and wearing resistance; 3) improvement of the processes, such as rapid solidification and laser annealing, not only excellent mechanical products of Mg alloys are gained by these processes, but also nano-structural coatings on surface are produced to increase the resistance to corrosion and wear. The new developments of surface treatment are to investigate the processes of nano-structural or glassy coatings on the surface of Mg alloys.
Key words: magnesium alloy; corrosion; surface finishing; protection design


