(1. 大連海事大學(xué) 交通運(yùn)輸裝備與海洋工程學(xué)院，大連 116026；
2. 大連理工大學(xué) 材料科學(xué)與工程學(xué)院 表面工程研究室，大連 116024)
摘 要: 采用強(qiáng)流脈沖離子束在束流密度為200 A/cm2、輻照次數(shù)為1~10次條件下對(duì)AZ31鎂合金微弧氧化膜進(jìn)行輻照改性處理。采用掃描電子顯微鏡對(duì)氧化膜的表面及截面形貌進(jìn)行表征；在Princeton Applied Research(PAR) 2273型電化學(xué)工作站測(cè)量氧化膜的極化曲線。結(jié)果表明：在束流密度200 A/cm2、5次輻照條件下氧化膜表面獲得連續(xù)、致密的改性層；以3.5% NaCl溶液為腐蝕液，氧化膜表面發(fā)生的腐蝕過(guò)程由輻照前的活化溶解向輻照后的鈍化−孔蝕擊穿轉(zhuǎn)變；在束流密度200 A/cm2、5次輻照條件下?lián)舸╇娢惶岣叩阶畲笾?#8722;800 mV(vs SCE)。強(qiáng)流脈沖離子束輻照產(chǎn)生的連續(xù)致密改性層是氧化膜耐蝕性改善的主要原因。
關(guān)鍵字: 鎂合金；強(qiáng)流脈沖離子束；微弧氧化；腐蝕
AZ31 magnesium alloy irradiated by high-intensity pulsed ion beam
（1. College of Transportation Equipments and Ocean Engineering, Dalian Maritime University, Dalian 116026, China;
2. Surface Engineering Laboratory, School of Materials Science and Engineering,
Dalian University of Technology, Dalian 116024, China）
Abstract:The microarc oxidation (MAO) films on the AZ31 magnesium alloy were modified by high-intensity pulsed ion beam (HIPIB) at an ion current density of 200 A/cm2 with 1−10 shots. The surface and cross-section morphologies of the MAO films were characterized by scanning electron microscopy (SEM). The polarization curves of the MAO films were measured by Princeton Applied Research 2273. The results show that a continuous and compact sealing layer forms on the MAO films by HIPIB with 5 shots. The polarization curves in 3.5% NaCl solution show that the corrosion behaviors of the MAO films transit from active dissolution of original films to pitting-breakdown of irradiated, and the breakdown potential achieves to −800 mV (vs SCE) at ion current density of 200 A/cm2 with 5 shots. The noticeable improvement in the corrosion properties of MAO films is attributed to the blocking effect of the sealing layer that hinders the process of electrolyte penetrating the MAO films to the magnesium alloy.
Key words: magnesium alloy; high-intensity pulsed ion beam; micro-arc oxidation; corrosion
