The nature of vacuum based processing is inherently problematic as the vacuum quality can be adversely affected by a range of effects that can contaminate the environment. If the level of such contamination exceeds acceptable limits, the quality of the produced parts will fall below standard and result in lower productivity and higher costs. The larger and more complex the vacuum processing chamber, the higher the probability of contamination, and the bigger the disruption to efficient production. Prediction and measurement of contamination within a vacuum is possible by residual gas analysis (RGA). Residual gas analysis can detect the presence and quantity of the gaseous species present, and as such is the most universal tool available to combat the difficulties experienced whilst vacuum processing. Traditionally vacuum residual gas analysis is performed by quadrupole mass spectrometry. A new method of residual gas analysis based upon remote plasma optical emission spectroscopy has overcome the drawbacks of using quadrupole based RGAs on large scale industrial vacuum systems. This remote plasma type of RGA operates over a wide range of vacuum pressures and is highly robust which guarantees continuous operation and avoids maintenance. The data provided can be used for smart digital control and monitoring of most forms of vacuum processes and ultimately ensures improved productivity.

Retained austenite may be helpful or detrimental to the life of heat-treated components, but it can be difficult to accurately measure in manufactured steels. Commonly used visual sample investigations are subjective and often incorrect, magnetic measurements require part-specific calibration, and electron backscattering involves expensive equipment, intensive sample preparation, and long measurement times. Recent developments in X-ray diffractometry, however, provide measurements in minutes and can compensate for the influence of carbides in high-carbon steels as well as texture orientations in rolled sheet metals. This paper discusses the use of X-ray diffraction for measuring retained austenite and compares and contrasts it with other methods. It also provides a brief review of the formation of austenite and its effect on carburized gears, TRIP steels, and bearings.

Since the invention of the vacuum furnace in the 1950s and up until the 1970s, its primary use was for annealing aerospace components. In the 1980s, vacuum equipment began to be used for heat treating tools and dies. By the 1990s, the need for faster quenching of high-alloy steels led to the development of vacuum furnaces capable of quenching at pressures up to 20 bar. Prior to this, only certain hot-work steels and a few tool steels with small cross-sections could be satisfactorily hardened in vacuum furnaces. Today, it is understood that simply increasing quenching pressure does not necessarily yield optimal results. Modern vacuum furnace technology allows for the precise design of the entire quench curve to maximize material performance while minimizing distortion. Continuous advancements and new concepts, such as multi-directional cooling systems, separate quenching chambers, and integrated cryo-cooling systems, have led to oxidation-free and low-distortion vacuum heat treatment for a wide range of parts and materials. This paper demonstrates how modern vacuum furnace designs and processes can improve quenching and cooling. It includes proven heat treatment results and examples from the international tool and die industry, which has been utilizing this technology over the past 25 years.