Multiphase Kinematics Characteristics and Densification Mechanism of Iron-based Metalloceramics Functionally Gradient Materials via Combustion Synthesis Infiltration under an Ultra-gravity Field

Abstract:

Iron-based metalloceramics functionally gradient material (FGM) was prepared by combustion synthesis casting under an ultra-gravity field through using thermite system with Fe₃O₄/Al/Fe-based Cemented Carbide. Multiphase kinematics characteristics and densification mechanism of cemented carbide particles in ultra-gravity field were explored. The research results indicated that based on the Stocks rules, effect of translational speed of particles in high-temperature melts will be determined by density variation between the particles and melt, ultra-gravity coefficient, radius of particles, temperature and so on. Under certain ultra-gravity coefficient condition, material density was related to bubble size, existence time of iron melt. On the top of the material, there are mainly gathered two kinds of particles with ferrovanadium and ferrochrome, whose size will decrease follow the direction of ultra-gravity field. However, ferromolybdenum mainly gathered in the interface between FGM and 45 steel. The mostSofSdiscrepancies of distribution characteristics for different particles were exhibited because of their difference of density and melting point. The aspect leads to the gradient variation of hardness distribution for the FGM.

Key words:Iron-based metalloceramics; Combustion synthesis casting under an ultra-gravity field; Kinetics characteristics; Densification; Stocks rule