Aeronautical engineers are consistently searching for new and optimal materials to achieve specific applications throughout an airframe. There are a multitude of considerations affecting the structural design of an aircraft such as the complexity of the load distribution through a redundant structure, the large number of intricate systems required in an airplane and the operating environment of that airframe. All of the above criteria is governed primarily by weight savings. Thus, the optimal materials selected today and for the future of airframes are composite material and titanium.

Today’s “high tech” vacuum furnaces have evolved significantly as advancements in materials, controls, and process technologies have progressed. These furnaces were developed to enhance metallurgical quality, improve braze quality, reduce inter-granular oxide formation, and provide better control over heating and quenching processes. Since the introduction of the first vacuum furnace for brazing in the late 1950s and early 1960s, continuous improvements over the past 50 years have led to the development of the most advanced vacuum furnaces available today. A “high tech” vacuum furnace utilizes cutting-edge materials, innovative designs, sophisticated control systems, and advanced features to deliver high performance, efficiency, and productivity, all while maintaining low utility and maintenance costs.

In the fight against global warming and rising greenhouse gas concentrations, the European Commission established the European Directive 2005/32/EC to regulate CO2 emissions. This directive, along with several amendments, outlines eco-design requirements for energy-using products, emphasizing increased efficiencies. As a result, new standards and norms have been developed and updated, which must now be considered in new product engineering projects. Additionally, energy costs are continually rising and are expected to keep increasing in the future. Given these factors, the design of modern furnaces has evolved significantly. Newly designed vacuum furnaces are much more efficient than older models. Consequently, vacuum pumps and pump systems must also be designed to support these energy-saving efforts. While the primary priority for vacuum pumps and systems remains to reliably provide the required vacuum level and ensure trouble-free operation, energy-saving measures must not compromise furnace uptime. This presentation will demonstrate that modern vacuum solutions, including dry-compressing screw-type vacuum pumps and innovative blower designs, can help achieve energy-saving goals. It will also describe measures taken with conventional vacuum components, such as rotary-vane pumps and diffusion pumps, to meet the new energy-saving requirements.

The article describes the achievements and application of a new generation of HPGQ vacuum furnaces. Implementation of 25 bar quenching enables reaching hardening properties compared to the ones obtained with oil, while vacuum carburizing and nitriding additionally create a great potential for running different heat treatment and thermo-chemical processes as well as multiple processes combined in a single furnace cycle. Technical and technological aspects of the furnace exploitation are presented and operational costs reduction and energy saving are considered.