Effect of Powder Feed Rate on Mechanical Properties of Boron Carbide Coatings by Atmospheric Plasma Spraying (APS)

Boron carbide (B4C) is considered an ideal material for plasma-facing materials (PFMs) in nuclear fusion, due to a combination of excellent properties: high elastic modulus, chemical stability, low Z and melting point. In this paper, B4C coatings were fabricated onto tungsten (W) substrates using atmospheric plasma spraying (APS). The powder feed rate significantly affects the coating quality. effects different rates on properties sprayed including thickness, porosity, adhesion strength investigated. particle temperature velocity measured by diagnostic system DPV evolution. Phase evolution microstructure characterized x-ray diffraction (XRD) scanning electron microscopy (SEM). XRD analysis showed that main phase composition did not change compared with initial powder, surface was oxidized formed B2O3. It has been demonstrated increases then decreases increase rate. Under optimal 1 g/min, 11.38 MPa.