The second article in this series looks at materials testing, microstructural evaluation, mechanical testing, and residual stress and distortion using the DANTE Controlled Gas Quenching process.

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.

A new method to control distortion in difficult-to-quench geometries addresses the nonuniform cooling inherent in most gas quenching processes. This article describes the development of a controlled gas quenching prototype unit design and its operation. The prototype unit constructed was able to achieve great control within the temperature range of 400 to 100°C, using varying rates of temperature change.

Tests conducted on vacuum carburized and quenched shafts identify variables that increase distortion and the magnitude of residual stresses.

Supersonic spray technology (SST) cold spray enables metal consolidation that can dimensionally restore precision gauges and fixtures made from heat-sensitive aluminum alloys. This case study describes how a manufacturer of high-precision aluminum gauging fixtures used SST cold spray technology to salvage a number of high-value fixtures that were either incorrectly machined or simply worn beyond their useful life.

Industry 4.0 is an emerging technology trend in the manufacturing arena that emphasizes the connectivity of physical and digital process across product development cycles. This article presents some examples of how Industry 4.0 will affect heat treating operations.

Computer modeling is used in the design and development stages of induction hardening to optimize the process and to improve component quality including hardness, beneficial stress distributions, and reduced distortion.

This article explains why defining gas quenching in terms of bar pressure no longer applies and how a new definition based on heat transfer and cooling rate leads to a better understanding of which steels and what cross-sections can be hardened via gas quenching.

This article discusses the implementation of a stationary induction hardening process for crankshafts and camshafts and the measures taken to maximize production rates while controlling part distortion.

This article demonstrates how FEA-based tools are used to model residual stress and distortion in a full-float truck axle induction hardened and cooled at different rates. The effect of cooling rate on axial displacement is discussed.

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.