GKN Aerospace, a division of the GKN plc group, is reported to be investing and expanding its interests in Additive Manufacturing (AM) for aerospace applications with the additional aim of leveraging its expertise in this technology across all GKN divisions.
According to a presentation by Rob Sharman, head of Metallics Technology at GKN Aerospace based in Filton, Bristol, UK, given at a recent Societe Generale investors technology lunch (February 4, 2014), AM technology presents a massive opportunity to create complex metal shapes for airplane structures. Some of these shapes would be impossible to manufacture using conventional manufacturing methods.
The driver for introducing AM applications at GKN will be cost savings by almost eliminating the machining process, stated Sharman. Results have shown that manufacturing waste could be reduced by up to 90%, particularly significant in industries where high-cost materials such as titanium and nickel-base alloys are used.
Sharman gave the example of a complex shaped component which as a finished machined part weighed just 0.77 kg. When produced from bar stock by machining a starting weight of 4.88 kg was required with 4.08 kg ending up as machining swarf. Using AM technology the part produced from metal powder was 1.08 kg with just 0.31 kg of swarf being generated in finish machining of the part.
A further advantage of AM is the reduced lead time from part design to end user approval which using conventional manufacturing would be around 95 weeks. Using AM requires less than 12 weeks, stated Sharman.
However, challenges still remain with AM technology such as new quality assurance technique that need to be evaluated and certified. Nevertheless AM technology has made great strides over the past decade with production parts already flying in commercial aircraft. Compare this with composite materials which took over 40 years to become accepted in the aerospace industry, stated Sharman
GKN has already invested heavily in exploring many different associated technologies in AM, but is presently focusing on processes such as electron beam melting, selective laser melting, and direct metal deposition techniques. Sharman stated that the company is establishing new Centres of Excellence building on existing AM capability to build a global network. These include powder bed processes at Filton, UK, high rate deposition processes in St. Louis, USA, fine deposition in Trolhatten, Sweden and powder materials in New Jersey, USA.
GKN Aerospace had sales of around $3.5 billion in 2012 with 12,000 people employed at 35 sites around the world. The global Tier 1 supplier has a sizeable stake in both metallic and composite structural manufacturing for all the major aerospace constructors.