This article compares heat treat processes and furnace types that are typically used to harden gears.

This study looks at whether adding an annealing step to the heat treating process has an effect on residual stress and distortion on hypoid gear sets. Test results indicate that the annealing heat treatment introduced between gear set soft cutting and case carburizing helped to minimize distortion.

Newly developed nickel-titanium (NiTi) alloys are well suited for bearings and gears in demanding applications.

Stringent pressure control and gas species type both play an important role in minimizing the evaporation rate of not only copper, but other elements susceptible to evaporation in vacuum systems. The article describes a study investigating the effect of temperature, pressure, and carrier gas species on the amount of copper evaporation that occurs from copper foil test samples in low pressure carburizing.

Modeling shows that achieving required gear performance in a reduced gear size is possible by changing the steel grade and heat treatment parameters during the design stage. This article describes work in which virtual computer models using DANTE software are applied to help achieve gear size reduction by including steel grade hardenability and heat treatment parameters in the design process.

Engineers at the Ford Motor Co. are using integrated computational materials engineering (ICME) tools, allowing them to accurately simulate the heat treatment of gears and predict phase transformation kinetics and distortion.