扩散方式对不锈钢热浸镀铝镀层形貌的影响

• 作 者: 贾涓 朱微微 熊玮 周巨澜
• 机 构: 武汉科技大学材料与冶金学院,
• 出 处: 材料热处理学报
• 发表日期: 2014年S1期
• 关键词: 扩散方式 层形 抗高温氧化性能 热浸镀铝 微观形貌 真空扩散 扩散层 试样 内层 金属间化合物

以1Cr18Ni9Ti不锈钢为研究对象,对其进行热浸镀铝。热浸镀后分别采用了空气扩散、包膜扩散和真空扩散3种不同的扩散方式。借助SEM和EDS研究了扩散前后镀层的形貌、厚度和成分的变化,分析了扩散方式对镀层形貌和抗高温氧化性能的影响。结果表明,1Cr18Ni9Ti不锈钢热浸镀并经950℃扩散3 h后,获得了与基体结合良好的双扩散层组织。试样表面主要为Al2O3等金属氧化物,外层主要为FeAl3、MeAl等金属间化合物,内层主要为Fe3Al和AlNi等金属间化合物。包膜扩散试样中的镀层总厚度和内层厚度最大,抗高温氧化性能最好。

1Cr18Ni9Ti stainless steel as the research object, its hot dip aluminum. After hot dip coating were used in the air diffusion, diffusion and diffusion coating three different ways of diffusion. The morphology, thickness and composition of the coatings before and after diffusion were studied by SEM and EDS. The effects of diffusion modes on the morphology and high temperature oxidation resistance of the coatings were analyzed. The results show that, after hot-dip plating 1Cr18Ni9Ti stainless steel and diffused at 950 ℃ for 3 h, a double-diffused layer structure was obtained. The surface of the sample is mainly composed of Al2O3 and other metal oxides, the outer layer is mainly FeAl3, MeAl and other intermetallic compounds, the inner layer is mainly Fe3Al and AlNi intermetallic compounds. Coating diffusion sample in the total thickness of the coating and the inner layer thickness, the best high temperature oxidation resistance.