New methods evaluate steel hardenability in a standard gas quench test and heat transfer coefficient variation within a furnace gas quench chamber.

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.

Hybrid heat sinks produced via cold spray technology can be a cost effective and lightweight alternative for cooling electronics.

Because alloy steel hardenability is such an important factor in part manufacturing, the Center for Heat Treating Excellence (CHTE) is conducting research through simulations and laboratory testing aimed at learning more about the performance of gas quenching systems used to harden newer alloy steels. The primary goal of the study is to establish a standard method to evaluate gas-quench steel hardenability. Heat transfer coefficients will be determined for different gas pressures and during the cooling phase.

Oxide dispersion strengthened (ODS) alloys have potential to improve turbine blade temperature capability beyond that of superalloy single crystals. In this article, the case is made for the potential to replace single crystals as high-pressure turbine blades with ODS nickel-base alloys. ODS alloys combine proven technology, substantial gains in capability over today’s single crystal alloys, and a clear development path to overcome identified risks.

With the opening of Testbed 80, the largest engine testing facility in the world, Rolls-Royce plans to use its unique capabilities to accelerate the journey toward sustainable aviation technologies supported by the intelligent use of materials.

Vacuum solution nitriding is a promising technique for increasing the surface hardness, load-bearing capability, and fatigue strength of martensitic stainless steels without sacrificing corrosion resistance. This article examines the effects of nitriding pressure and temperature on surface nitrogen content and case depth in four martensitic stainless steels.

Experimentally derived surface heat flux rate data and computational fluid dynamics (CFD) software are helping researchers more accurately simulate liquid quenching processes. This article describes an approach where surface heat flux rates are determined experimentally in a precisely controlled flow boiling test system. This data is then used to build CFD models that are proving to be quite accurate in quenching process simulations.

With the goal of improving aircraft efficiency, Boeing in collaboration with NASA Glenn Research Center (GRC) have developed and successfully flight tested environmentally activated vortex generators that passively, repeatedly, and accurately retract during cruise and deploy during take-off and landing phases. The capability discussed in this article is based upon recent advancements in shape memory alloy rotary-actuation technology, which included improved alloy systems, design tools, best practices, published standards, and previous wind tunnel and flight test demonstrations.

Nanostructured tungsten-tungsten carbide chemical vapor deposition (CVD) coatings provide a practical, technical, and commercially viable alternative to hard chrome plating for aircraft components.

Successful use of composite materials requires a thorough understanding of their mechanical properties. Although a range of mechanical tests is required to obtain data, the aerospace industry has already developed, validated, and standardized these test methods. This article reviews some of key test methods used with composites.

Flash processing, a new heat treatment for steels based on the concept of rapid thermal cycling, has been shown to achieve new levels of strength and ductility. This article describes the process, its effects on microstructure, and the phase transformations involved. It also discusses current and potential future applications.

A new welding process known as hybrid induction arc welding (HIAW) or high deposition arc welding (HiDep) uses a hybrid approach to reduce—or even eliminate—weld distortion and greatly increase productivity. Operating directly in front of the arc welding torch, a portable induction coil heats the surfaces of the weld to, or near, the melting point. Heat generated by the welding arc is primarily used to melt the welding wire. This novel process operates at speeds two to four times faster than conventional arc welding and substantially reduces weld distortion.

Heat treaters regularly seek ways to prevent and reduce rework and scrap loads by implementing procedures and tools to make sure the heat treating process meets customer expectations and specifications. One process parameter requirement is to ensure consistent atmosphere carbon content. Measuring carbon absorption into steel is commonly done to verify atmosphere consistency. This article describes an atmosphere carbon potential analyzer that provides a cost-effective way to measure carbon using a wire coil that functions in a way similar to using shim stock.

Properties and performance of lower cost “simple” alloy steels processed using induction coupled thermomagnetic processing can rival those of conventionally processed, expensive specialty alloys. This article discusses some of the demonstrated improved mechanical properties achieved for steels in a industry-government project that evaluated the viability of processing metals in a strong magnetic field.

An industry pioneer shares a historical overview of the early days of single crystal superalloy development.

Early consideration of scale-up requirements can help circumvent downstream problems when implementing thermal processes for the production of new materials and product forms. Examples are given showing how success is achieved when scaling opportunities and challenges are identified early in the development process.

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.

A novel hot zone design featuring new graphite boards reduces heat loss and improves overall hot zone power requirements.

Case studies from a range of industries illustrate how advanced additive manufacturing capabilities optimize both material performance and value. The materials discussed are Inconel 718, Ti-6Al-4V, aluminum F357, and Hastelloy X.