Low-temperature processing of Fe-Al intermetallic coatings assisted by ball milling
Low-temperature processing of Fe-Al intermetallic coatings assisted by ball milling
复制标题
球磨辅助Fe-Al金属间化合物涂层的低温加工
DOI：
10.1016/j.intermet.2005.04.019
复制
发表时间：
2006-01-01
期刊：
影响因子：
4.4
通讯作者：
Gao, W
中科院分区：
文献类型：
--
作者：
Zhan, ZL;He, YD;Gao, W
提出了一种在钢表面制备Fe-Al金属间化合物涂层的新工艺。该技术是在反应罐中加入铝粉、氧化铝填料、氯化铵活化剂和铁铬铝合金球，利用机械振动进行反应。操作温度为440 - 600 ℃。该技术在560 ℃下处理15分钟产生厚度为17 μ m的涂层，处理120分钟产生厚度为90 μ m的涂层。涂层看起来是均匀的，具有高密度和无孔隙，并且具有优异的对基底的粘附性。涂层主要由eta-Fe 2Al 5和少量的theta-FeAl 3和beta-FeAl组成，并呈现纳米结构。显微组织研究表明，低温下金属间化合物相的形成机制复杂，包括球磨在基体上形成薄Al层;富Al相的形核、生长和初始合金层的形成;剧烈塑性变形提高局部温度并产生纳米结构; Fe的快速向外扩散和Fe-Al金属间化合物的形成。与传统的铝包渗工艺相比，该技术显著降低了处理温度和时间，为工业扩散涂层提供了一种新的方法，节省了大量的能源和时间。(c)2005爱思唯尔有限公司保留所有权利。
A novel technique has been developed to produce Fe-Al intermetallic coatings on steel. This technique applies mechanical vibration to a retort, which is loaded with Al powder, alumina filler, ammonium chloride activator and FeCrAl alloy balls. The operation temperature was from 440 to 600 degrees C. This technique produced coatings with thickness of 17 mu m for 15 min and 90 mu m for 120 min treatment at 560 degrees C. The coatings appear to be homogeneous, with a high density and free of porosity, and have excellent adherence to the substrate. The coatings consisted mainly of eta-Fe2Al5 with small amounts of theta-FeAl3 and beta-FeAl, and exhibited a nano-structure. Microstructure studies suggested that the formation of the intermetallic phases at a low temperature has a complex mechanism, including the formation of a thin Al layer on the substrate by ball milling; Al-rich phases nucleation, growth and formation of an initial alloy layer; severe plastic deformation which increases the local temperature and produces a nano-structure; and fast outward diffusion of Fe and formation of Fe-Al intermetallics. This technique reduced the treatment temperature and duration significantly compared with the conventional Al pack cementation processes, providing a new approach to industrial diffusion coatings with great energy and time savings. (c) 2005 Elsevier Ltd. All rights reserved.