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.
Despite the widespread commercial use of hydrogen, not all of the flammability limits of the gas are known. Experiments were performed to determine hydrogen reaction limits in a partial pressure vacuum to allow the design of a vacuum furnace system having the necessary safeguar
Heat treatment standards are stricter in the aerospace industry than in the medical industry where lives are on the line. This doesn’t make sense and something is being done about it. Recently, I was asked to give a vacuum heat treating presentation to a group of design engineers at a large medical device company. The lead engineer asked if I would help educate his team on this subject primarily because they had just experienced a major failure caused by improper heat treatment. After learning more about the failure, it became evident that the medical device engineers in that room could learn a great deal from the aerospace industry, especially regarding knowledge of aerospace materials and secondary aerospace processes. It also became apparent that an industry-managed oversight program addressing the technical competency required in special processing was necessary in order for medical device companies to improve design and manufacturer of future medical devices.
Increased usage of refractory metals, titanium and their alloys in the aerospace and electronics industries has led to the use of the hydride/dehydride (HDH) heat treating process for recovery of spent materials. The HDH process has been known for many years in the manufacturing of transition-metal powders.
The fuzzy definitions of “raw material” and “parts” in specifications create variable and debatable heat treating quality standards.
Heat treating is the unsung hero of the commercial and military aviation industries. Much like the support staff behind any good play or movie, and the mom behind the Olympic athlete, heat treating of critical aerospace parts is relegated to the background, to the fine print of the credits…if at all. But if it weren’t for heat treating, planes wouldn’t fly, ships wouldn’t sail, submarines wouldn’t dive, and cars wouldn’t drive. This article introduces you to the technical world of vacuum heat treating and why vacuum thermal processing is vital to the aerospace and defense industries. First, let’s nail down what we mean by “heat treating.” In simple terms, heat treating is cooking metal much like you would cook food – with a predetermined recipe and desired outcome in mind. Metal is placed into an oven, or more accurately a furnace (ovens typically don’t handle temperatures over 1,000°F), and precisely held at a specified temperature for a pre-determined period of time. The metal is then cooled either slowly or quickly depending on what properties are desired. Thermal processing can make the metal harder, softer, stronger, more flexible, more rigid, more wear resistant, chemically altered, or a host of other desirable properties.
When gas quenching, the minimizing of heat treat distortion is gears may be a matter of high pressure and high velocity. That’s what Solar Atmospheres thinks, that’s why the heat treat company sends helium gas into its vacuum furnaces at more than 100mph.