Thermodynamic Properties of Metal-Carbon Melts

Abstract

The partial and total enthalpies of mixing of Si-C and Ni-C liquid alloys at 2000 K are determined by isoperibol calorimetry. The mixing enthalpies in these systems are found to be small and negative, in agreement with earlier results. The thermochemical properties of dilute Al-C solutions are studied at 1773 K for the first time. The mixing enthalpies of metal-carbon melts are estimated from the standard enthalpies of formation of metal carbides. The calculated mixing enthalpies of liquid metal-carbon alloys agree with experimental data.

Binary Phase Diagrams and Thermodynamic Properties of Silicon and Essential Doping Elements (Al, As, B, Bi, Ga, In, N, P, Sb and Tl)

“… ( a ) Enthalpy of mixing of the B-Si liquid; —: [ 143 ]; □: [ 166 , 168 ] and ○: [ 150 , 165 ] at 1600 °C; -----: [ 167 ] at 2127 °C; ( b ) Average activity values of B and Si in the B-Si liquid; boron (□) and silicon (○) [ 142 ] at 1577 °C; ----: [ 167 ] at 2127 °C. …”

Combustion synthesis of single‐phase Al4SiC4 powder with assistance of induction heating

“…It is considered that when the temperature of the green pellet reaches melting point of Al, first the reaction between Al and Si takes place, and then Al‐Si liquid wets surface of carbon black particles and some carbon dissolution into the melt occurs. Enthalpy of carbon mixing in diluted Al melt is known to be negative (−59 kJ/mol). As can be seen from Figure , the first exothermic peak in the temperature‐time profile starts from ~700°C and has a maximum at 900°C, which relates to the area of aluminum melting.…”

Effect of Heat Treatment Temperature on Microstructure and Properties of PM Borated Stainless Steel Prepared by Hot Isostatic Pressing

“…Boron segregation to austenite grain boundaries is considered to occur by a non-equilibrium segregation mechanism [ 10 ] and is mainly concentrated on the grain boundary, filled with defects, and forms boron phases with Fe, Cr, or Ti. The interaction between dissimilar atoms becomes stronger in the order Co–B < Ni–B < Mn–B < Fe–B < Cr–B [ 19 ].…”

“…In the heat treatment process, boron diffuses to grain boundaries or defects in grains because the boron diffusion coefficient [ 8 ] is larger than that of iron and chromium in austenite [ 20 ]. The binding force of boron with iron and chromium is greater than that of other elements [ 19 ], so chromium and iron diffuse to the enrichment area of boron, and the content of chromium and iron in the boron phase is different from that of the austenite matrix phase.…”