Heat Transfer Ratio on Jominy Test

Cooling curves at surface of Jominy specimen, quenched from 800℃ are measured. These curves at various distance from quenched end, approximately are obeyed Newton's law. Theoretical cooling curves, combined cooling curves of semi-infinite plate with water quenched end and infinite cylindrical bar cooled on air, are calculated. As result of comparison with measured and calculated cooling curves, values of heat transfer ratio h at quenched end and air cooled surface, are obtained h=1.20 cm^^-1, 0.009 cm^^-1 respectively.