高频电脉冲沉积铝化物微晶涂层的氧化行为

OXIDATION BEHAVIOUR OF ALUMINIDE MICRO- CRYSTALLINE COATINGS PRODUCED BY HIGH- FREQUENCY ELECTRO-SPARK DEPOSITION

采用新型高频电脉冲沉积技术在１Ｃｒ１８Ｎｉ９Ｔｉ不锈钢表面上获得了晶粒尺寸约为几十到几百纳米的微晶铝化物涂层在１０００℃空气中恒温氧化１００ｈ的实验结果表明：获得的铝化物微晶涂层具有优异的抗高温氧化性能，而且显著提高了氧化膜的抗剥落能力．施加铝化物涂层后，１Ｃｒ１８Ｎｉ９Ｔｉ不锈钢的氧化膜由以 Ｆｅ的氧化物为主转化为以Ａｌ的氧化物为主．由于材料表面的铝化物涂层为微晶层，提高ＴＡｌ的选择氧化能力和氧化膜的粘附性．

Aluminide micro-crystalline coatings with the grain size from several tens to several hundreds nano meters were developed on the 1Cr18Ni9Ti stainless steel by means of a high frequency electro-spark deposition technique. The oxidation results conducted in air at 1000℃for 100h show that the aluminide micro-crystalline coatings exhibited superior oxidation resistance and improved the adhesion of oxide scales greatly. The oxides formed on 1Cr18Ni9Ti transformed from iron oxides to aluminia after the application of aluminide micro-crystalline coatings. The micro-crystalline structure of the coationgs enhanced the selective oxidation tendency of aluminium, increased the high-temperature creep in chide scales as well as improved the adhesion of oxide scales.