Meeting a challenge: General Industry Coverage

Beryllium provides many desirable properties for a host of applications, such as aerospace and automotive. These include having a high melting point with excellent thermal conductivity, being stiffer than steel by weight, and being extremely lightweight. “The only lighter metal is lithium, but you can’t expose lithium to oxygen without it spontaneously combusting,” said Anthony Dutton, CEO and director of materials provider IBC Advanced Alloys Corp.

When beryllium is alloyed with aluminum, the resulting components are 22 percent lighter than aluminum ones and provide increased stability through a large operational temperature range. Machining beryllium-aluminum (Be-Al) billets, typically made of hot isostatic-pressed metallic powders, is time-consuming, and the resulting chips can’t be recycled as easily as, say, steel or copper. Dutton explained this is because the chips must be rinsed, repowdered and essentially put back through the production cycle. “In terms of an economic analysis, you would effectively account for that yield loss being 100 percent.”

Beralcast beryllium-aluminum parts are suitable for up to 80 percent of the applications for that alloy, including this reconnaissance pod electrical enclosure for a fighter plane.

One solution to this problem is casting Be-Al alloys to a near-net shape and only finish-machining specific features for precise interfaces and tight tolerance requirements that cannot be achieved with a raw investment casting. This would reduce the cost and lead times for the parts.

One challenge, though, is the that the melting and freezing temperatures of the two metals are extremely divergent. This makes it difficult to get both to behave in a uniform manner in the same temperature range and ensure equal distribution when casting without causing the problem of aluminum segregation.

IBC’s subsidiary, IBC Engineered Materials Corp., Willington, Mass., overcame this challenge by developing a proprietary process, becoming the only company that can successfully cast the alloy, according to Dutton.