SUBSTRATE-COATING THERMAL INTERACTION DURING HIGH-VELOCITY OXYFUEL SPRAYING .2. STRUCTURE FORMATION

In the present paper the mathematical simulation of the formation of t he structure of both the substrate and the coating during high velocit y oxyfuel (HVOF) splaying is presented. The variation in the solidific ation velocity the thermal gradient, and the cooling velocity in the f irst coating layer as well as the fusion (solidification) velocity, th e thermal gradient, and the heating (cooling) velocity in the substrat e are studied. The formation of the amorphous structure in the coating and the crystalline structure in the substrate are discussed. The opt imal conditions for the development of the fine and dense crystalline structure in the substrate are investigated. The results obtained agre e well with the experimental data.