What Do We Know, What are the Current Limitations of Suspension HVOF Spraying?
What Do We Know, What are the Current Limitations of Suspension HVOF Spraying?
复制标题
DOI：
10.1007/s11666-015-0264-9
复制
发表时间：
2015-10-01
影响因子：
3.1
通讯作者：
Gadow, R.
中科院分区：
文献类型：
--
作者：
Killinger, A.;Mueller, P.;Gadow, R.
悬浮喷雾在过去几十年中不断发展，现在正处于商业应用的门槛。与标准粉末喷涂方法（主要是直流等离子喷涂和（高速）火焰喷涂）相比，悬浮喷涂显然不会取代这些成熟的技术，但可以通过添加新的涂层性能来扩展它们。但仍有许多问题有待解决。悬浮液与热气流的相互作用比普通粉末喷涂过程复杂得多。在 HVOF 的情况下，当使用轴向喷射到燃烧室中时，不可能直接观察液体火焰相互作用。本文讨论了悬浮液 HVOF 喷涂（高速悬浮火焰喷涂）的现状，包括火炬概念、TopGun 系统中的火炬配置以及不同的喷射器概念及其对悬浮液雾化的影响。讨论了悬浮液的流变学和热力学性质的作用，主要由溶剂类型和固体含量给出。给出了不同的可用诊断方法和系统及其各自的适用性的概述。显示并讨论了几种氧化物陶瓷的涂层特性及其可能的应用。
Suspension spraying has evolved during the past decades and now is at the threshold of a commercial utilization. Compared to standard powder spray methods, mainly DC plasma spraying and (high velocity) flame spraying, it is quite clear that suspension spraying will not replace these well-established technologies but can extend them by adding new coating properties. Still there remain many issues to be solved. Suspension interaction with the hot gas stream is much more complex than in ordinary powder spray processes. In case of HVOF when axial injection into the combustion chamber is used, a direct observation of the liquid flame interaction is not possible. This paper discusses the present status of suspension HVOF-spraying (high velocity suspension flame spraying) including torch concepts, torch configuration in case of a TopGun system as well as different injector concepts and their influence on suspension atomization. The role of suspensions is discussed regarding their rheological and thermodynamical properties, mainly given by the solvent type and the solid content. An overview of different available diagnostic methods and systems and the respective applicability is given. Coating properties are shown and discussed for several oxide ceramics in respect to their possible applications.