Elucidation on Reactions Thermodynamics and Kinetics of OFC-A of Steels

Abstract

The basic principles of Oxyfuel cutting of metals lie in rapid high-temperature oxidation of the cut metal. Considerable proportion of the published work on the subject of oxygen cutting, the details of the oxidation reaction are overlooked or confused. Most often, physical characteristics of oxidized material is attributed to that of iron rather than iron oxide. The analysis of the oxidation reactions pertinent to Oxyfuel cutting of steels has also been majorly ignored. The oxidation process of iron and steel though similar in some respects, yet, in other aspects, show significant differences. This paper presents experimental and theoretical elucidation on reactions thermodynamics and kinetics of oxyfuel cutting processes of steel. Six 10mm metallurgy steel rods of different wt% C were flame cut using different acetylene and oxygen pressures. The composition of the steel rods used ranged from 0.16 wt% C to 0.33wt% C. Acetylene pressures used ranged from 3.45 x 10-2 N.m-2 to 5.52 x 10-2N.m-2, while oxygen pressure ranged from 2.76 x 10-1N.m-2 to 3.17 x 10-1 N.m-2. The result shows that the cutting rates decreased with carbon content of the steel as a result of reduction of iron oxide during decarburization reactions. Theoretical models of the thermodynamics and kinetics of cutting process pertinent to steels are also discussed.