一种新型热喷涂WC-FeCrAl粉末与标准WC-Co粉末的对比研究

本文对比分析了一种WC-FeCrAl基喷涂粉末和标准WC-Co粉末的性能、喷涂焰流特点、涂层的喷涂堆积特点和涂层性质,并对两种喷涂粉末和喷涂涂层进行了XRD分析.任何类型的热喷涂涂层是由单个喷涂粉末堆积而成,本文以此为研究切入点.一种新的检测方法可以在极短的暴露时间中记录喷涂焰流中喷涂粉末的行程从而实现对这些粉末状态的检测1].研究发现,对于这两种粉末材料,喷涂参数和涂层性质之间的相互依赖性大体是一样的,不同之处主要在于喷涂过程中材料的相稳定性.XRD测试表明,标准的WC-Co粉末中,WC没有表现出任何可识别的相转移,然而却在WC-FeCrAl粉末中发现W2C的形成以及基材的氧化.

Comparative Investigation of Standard WC-Co and a New WC-FeCrAl Feedstock Powder

The presented work compares a new WC-FeCrAl-matrix feedstock powder with a standard WC-Co powder. The investigation covers the powder analysis, spray jet properties, splat flattening and coating properties, as well as, XRD analyses of the feedstock powders and as sprayed coatings. As the formation of single splats sets up the foundation for any thermal spray coating, this step was chosen as the major subject of investigation in this paper. A new method to create a footprint of splats from a spray jet with an extremely short exposure time was used to perform these splat examinationstll It was found, that the interdependencies between spray parameters and coating properties are generally the same for both materials. Differences occurred in the phase stability of the materials during the spraying process. In XRD measurements the standard WC-Co material did not exhibit any recognizable phase transformations of the WC, while a significant formation of W2C and oxidation of the matrix was observed for the WC-FeCrAI powder.