Fe2B间距及排列方式对定向凝固Fe-3.5B合金耐锌液冲蚀性能的影响

Effect of Fe2B space and orientation on erosion-corrosion properties of directional solidification Fe-3.5B alloy in flowing l

摘要:

利用旋转盘技术研究了不同Fe2B间距及排列方式下的定向凝固Fe-3.5B合金在流动锌液中的冲蚀行为。通过扫描电镜观察冲蚀界面形貌特征，考察了定向合金中Fe2B排布方式及间距对锌液冲蚀性能的影响。结果表明，流动锌液冲蚀过程中Fe2B相平行于锌液流动方向的定向试样，（即横向试样，标记为Fe2B∥试样），其锌液冲蚀速率随着冲蚀时间的延长快速降低，而Fe2B相垂直于锌液流动方向的定向试样，（即纵向试样，标记为Fe2B⊥试样），其锌液冲蚀速率降低缓慢。随Fe2B间距增加，定向合金横向试样的锌液冲蚀率先增加后降低。当Fe2B间距为3.67μm时，定向凝固Fe-3.5B合金横向试样冲蚀速率最小，而Fe2B间距为1.87μm时定向凝固Fe-3.5B合金纵向试样冲蚀速率最小。冲蚀界面微观形貌对Fe2B间距具有尺寸依赖性，具有适当Fe2B间距的横向试样在冲蚀界面与定向产物形成良好的冲蚀层过渡结构，表现出界面 “界面钉扎” 效应，从而很好地抑制了锌液冲蚀损伤。

Abstract:

The erosion-corrosion behavior of directional solidification Fe-3.5B alloy in flowing liquid zinc was investigated by rotating disk technique. Microstructural morphology of erosion-corrosion interface was observed by SEM, the effects of orientation and space of Fe2B on the erosion-corrosion in the flowing liquid zinc were analyzed. The results show that the erosion rate quickly decreases with the extension of erosion time when the Fe2B is parallel to the flowing direction of liquid zinc (labeled Fe2B∥ sample) and the erosion rate slowly decreases with the extension of corrosion time when the Fe2B is perpendicular to the flowing direction of liquid zinc (labeled Fe2B⊥ sample). The erosion rate of directional solidification Fe-3.5B alloy (Fe2B∥ sample) increases first and then decreases with the increase of Fe2B space. When the space of Fe2B is 3.67μm, the corrosion rate of transverse sample possesses the minimum value of erosion-corrosion rate. The corrosion rate of longitudinal sample reaches the minimum value of erosion-corrosion rate when the space of Fe2B is 1.87μm. The microstructure of erosion-corrosion interface is dependent on the Fe2B space, and the appropriate Fe2B space is beneficial to form a good erosion compound layer which shows an “interface pinning effect” and inhibits erosion-corrosion.