Search Results for quench distortion

This article provides the basics of overall quench process distortion. It describes the influence of quenching processes on the generation of distortion. Examples for the distortion behavior of different types of components are presented. Then, comparisons between different quenching processes are provided. The article presents some possibilities for minimization of shape changes by the quenching process itself. Several suggestions are given for quenching processes in evaporating fluids. An example is provided for out-of-roundness reduction for rings by well-defined inhomogeneous quenching in a gas nozzle field. Another example shows how intensive and high-speed quenching can help to reduce the bending of shafts with an asymmetrical cross-section. The last example shows the result when external loads and nonsymmetric quenching act together. The article also presents test samples for the judgment about distortion potential arising from heat treatment equipment.

In the case of steels, heat treatment plays a fundamental role because no other process step can manipulate the microstructure in order to fulfill such a wide variety of possible in-service conditions. This article addresses heat treatment with regard to hardening and subsequent tempering of steel components in order to optimize tribological properties. It focuses on the heat treatment of tempering and bearing steels and on volume changes that take place due to phase transformations. Plastic deformations that occur due to shrinking and phase transformation are also discussed. The article also describes the generation of thermal, transformation, and hardening residual stresses.

This article presents the background to the CALculation of PHAse Diagrams (CALPHAD) method, explaining how it works, and how it can be applied in industrial practice. The extension of CALPHAD methods as a core basis for the modeling of generalized material properties is explored. It informs that one of the aims of CALPHAD methods has been to calculate phase equilibria in the complex, multicomponent alloys that are used regularly by industry. The article discusses the application of CALPHAD calculations to industrial alloys. Modeling of general material properties, such as thermophysical and physical properties, temperature- and strain-rate-dependent mechanical properties, properties for use in the modeling of quench distortion, and properties for use in solidification modeling, is also reviewed. The article also describes the linking of thermodynamic, kinetic, and material property models.

This article provides an overview of the effects of various material- and process-related parameters on residual stress, distortion control, cracking, and microstructure/property relationships as they relate to various types of failure. It discusses phase transformations that occur during heat treating and describes the metallurgical sources of stress and distortion during heating and cooling. The article summarizes the effect of materials and the quench-process design on distortion and cracking and details the effect of cooling characteristics on residual stress and distortion. It also provides information on the methods of minimizing distortion and tempering. The article concludes with a discussion on the effect of heat treatment processes on microstructure/property-related failures.

Press quenching is a specialized quenching technique that can be utilized during heat treatment to minimize distortion of complex geometrical components by using specialized tooling for generating concentrated forces that constrain the movement of the component in a carefully controlled manner. This article provides a detailed account of the fundamental components of quenching machines, including the upright machine section, control panel, lower die table, tooling, and the base. In addition, it summarizes the critical factors affecting component distortion during press-quenching.

Mathematical models have been used for over five decades in industrial heat-treating operations. Most of these modeling efforts have emanated from academia or research institutes, with the primary approach of mathematically capturing heat-treating processes and validating quality predictions. In this article, a contrarian but more realistic scenario is considered, where two industrial problem descriptions become the starting point. The technical complexity of the industry problem has been elaborated for a deeper understanding of the issue along with elaboration of the approach and potential methods for determining a solution. Then, quantitative analyses of practical industrial problems are demonstrated. Finally, the potential shift in these approaches with the advent of Industry 4.0 is outlined.

This article provides an overview of heat treatment processes, namely, solution heat treatment, quenching, natural aging, and artificial aging. It contains a table that lists the various heat treatment tempers commonly practiced for nonferrous castings. The article describes microstructural changes that occur due to the heat treatment of cast alloys.