Optimizing gas quenching

The need by heat treaters to boost productivity and improve metallurgical properties while minimizing environmental impact led vacuum furnace manufacturers to place increased emphasis on enhancing gas quenching performance. To achieve the goal of a superior vacuum furnace gas quenching system, a better understanding of gas cooling fundamentals was first acquired and then applied to such variables as gas type and pressure, blower motor power, and furnace design features. This resulted in dramatic improvements in gas quenching over the past decade. This article presents a historical perspective, the role of the cooling coefficient, assessing furnace performance, 'obstacles' to gas quenching, and future developments in the field.