碳化硼涂层显微结构和性能研究

Relationship Between Properties and Microstructure of Plasma Sprayed Boron Carbide Coating

本文研究了碳化硼等离子喷涂涂层的显微结构和电导率．发现涂层中存在多种显微结构，颗粒状和板状的碳化硼相为主相;涂层中金属Ｆｅ杂质相的存在是涂层电导率出现异常的决定因素;碳化硼涂层中还发现了由Ｂ、Ｏ和Ｆｅ三种元素组成的杂质相，其显微硬度比碳化硼低，这是碳化硼涂层显微硬度同碳化硼陶瓷相比要低的一个重要原因．

The microstructure and the electronic conductivity of plasma sprayed boron carbidecoating were studied. The results show that B_4C phase in the coating exists in two major structuregrained and flaky structures. Metal Fe as the impurity phase in the coating is the key factorresulting in the abnormality of electronic conductivity of B_4C coating. Another impurity phase,which consists of B, C and Fe elements, will decrease the microhardness of B_4C coating.