Enhanced performance operating envelopes for aerospace platforms continue to challenge industry limits. Aerospace platform operators demand extreme performance in harsh environments from the aircraft, UAVs, and satellites they deploy today: lighter weight, greater strength, superior fuel efficiency and operational range, vibration-mitigated platforms, low coefficients of thermal expansion, better corrosion resistance — the list goes on.

Beryllium is the second lightest metal (after lithium), has excellent thermal conductivity, and — weight for weight — is stiffer than steel.

Whether in defense or commercial applications, product competition continues to drive the performance envelope in design, materials selection, and manufacturing of these systems, all the while working to contain costs and meet challenging delivery schedules. In general, materials technologies to increase performance are desired and can be implemented, but they must come with an acquisition or operational cost decrease.

Few factors have proven more critical to expanding aerospace system capabilities as the development of new advanced materials and high-performance alloys. In some systems, performance breakthroughs are largely due to next generation materials and the methods of their manufacture and the remarkable characteristics those materials convey.

This is increasingly the case with one set of high-performance alloys — those made with the metal beryllium.

Beryllium’s Advantages

Beryllium is simply an amazing metal. It is the second lightest metal after lithium, but is also as stiff as steel. In fact, its modulus of elasticity is 50% greater than steel. It has a very high melting point (1,287°C) and a low density (1.844 g/cm3). It resists oxidation and corrosion in the air.

When alloyed with aluminum, copper, and other metals, beryllium’s application in aerospace and other applications really begins to shine.

For one, the low coefficient of thermal expansion (CTE) provided to these alloys by beryllium results in significantly less expansion and fewer temperature induced stresses and optical distortions across a range of environments. These are critical characteristics for many aerospace uses.

Beralcast® Material

Investment cast parts made with Beralcast®

Few companies in the world have successfully mastered the processes and technologies required to make high-performance alloys with beryllium. One such company, IBC Advanced Alloys, has carved out a particularly unique niche with this material.

IBC operates two divisions: the Franklin, Indiana-based Copper Alloys Division, which manufactures and distributes a variety of copper alloys as castings and forgings, including beryllium-copper, chrome-copper, and aluminum-bronze; and the Wilmington, MA-based Engineered Materials Division, which specializes in cast beryllium-aluminum alloys.

The Engineered Materials division is where IBC has begun to make its mark in the aerospace industry.

One of the beryllium-aluminum alloys made by IBC is known as Beralcast®363. Beralcast® is made from 65 percent beryllium and 35 percent aluminum. It is particularly well suited for applications that require high specific stiffness for fast-acting systems that require high precision, such as imaging systems. The material’s excellent thermal conductivity and low thermal distortion is an excellent combination for electronic and battery enclosures.

Beralcast® in the F-35 Lightning II Fighter

Electro-Optical Targeting System (EOTS)

Given these characteristics, it is no surprise that IBC’s Beralcast® material is now flying on the F-35 Lightning II jet fighter.

IBC manufactures the azimuth gimbal housing of the F-35’s Electro-Optical Targeting System (EOTS) with its Beralcast® material. EOTS is Lockheed Martin’s affordable, high-performance, lightweight, multi-function system that provides precision air-to-air and air-to-surface targeting capability. The low-drag, stealthy EOTS is integrated into the F-35 Lightning II's fuselage with a durable sapphire window and is linked to the aircraft's integrated central computer through a high-speed fiber-optic interface.

Due to the critical role of the electro-optical sub-systems within EOTS, coupled with the cost-effective method of manufacture for the investment cast Beralcast® gimbal housing, IBC is helping the EOTS platform simultaneously meet the extreme performance and cost reduction goals set by the F-35 Joint Program Office.

IBC completed a multi-year certification process with Lockheed Martin before it began producing the EOTS azimuth gimbal housing for the F-35. The certification process was not easy, given that the azimuth gimbal housing represents the most complex geometry of all beryllium-aluminum alloy parts designed for use in the F-35. But the upside in completing the certification process is substantial; now that IBC has qualified its material and capabilities on Lockheed’s most complex geometry, IBC can produce virtually any other geometries needed in their system.

Near-Net Shape Casting

IBC makes precision parts from beryllium-aluminum alloys using a proprietary and highly unique manufacturing process – vacuum investment casting. The casting process produces near-net-shape geometries in a high-purity environment. These geometries are closer to the finished size and shape of the custom part designed, thereby reducing post-production machining. That’s a huge advantage when making specialized beryllium alloy components for the aerospace industry.

Perhaps the best way to understand the unique value of this technology is to compare it to traditional manufacturing techniques for custom beryllium-aluminum products.

Until IBC successfully launched its proprietary vacuum casting process, virtually all beryllium-aluminum alloy parts were manufactured through a powder metallurgy process. This approach involves a relatively high cost of manufacture. The materials to be combined first have to be melted. Then they are formed into powders, which have to be handled very carefully due to health and safety concerns, and how they are blended in different amounts up to the preferred chemistry level. Once this has been done, the products are poured into a steel can and finally Hot Isostatically Pressed (HIPed) into a billet at high temperatures and pressures. This generates a large block of material that has to be sectioned into billets that are then machined down to the final component. For some complex geometries, the machining process alone can take months to complete.