THE BENEFITS OF ADDITIVE MANUFACTURING AND ITS USE BY GENERAL ELECTRIC FOR AEROENGINE APPLICATIONS

Additive manufacturing (AM), more commonly known as 3D printing, is the future of manufacturing, repair, and maintenance and has even been described as "the Third Industrial Revolution" by the Journal of Minerals, Metals, and the Material Society (JOM). This is due to the undeniable benefits of AM in speed, efficiency, material waste reduction, and the ability to produce intricate structures. The AM process gets its name from the fact that it adds material, unlike traditional machining and lathing, which involve material removal. In AM, layers of metal powder are successively added to a build table and laser melted in a controlled and localized manner—using a method known as selective laser melting (SLM)—until a 3D object is formed. The remarkable precision of this process allows manufacturers to build parts within stringent tolerances, no matter how complex the structure. The benefits of AM are of direct relevance to sustainability—an increasingly important aspect of engineering. A focus of sustainability is to develop technologies that maintain long-term service capabilities without long-term consequences. AM’s ability for advanced design and efficiency (and thus a decreased environmental footprint) clearly makes it a sustainable technology with significant potential. Aside from its potential and sustainability, AM is already exploited in a number of industrial applications. The aviation industry has taken an active interest in the technology in efforts to reduce aircraft weight and increase fuel efficiency—which means money saved for companies and consumers alike, together with a decrease in greenhouse gas emissions. One major company doing so is General Electric (GE), which has developed additive manufactured products such as the LEAP engine fuel nozzle and an advanced turboprop. GE has successfully translated the benefits of AM into components of their jet engines and there is no doubt that other manufacturing companies will follow its lead. Key Words—3D printing, Additive manufacturing, Advanced turboprop, Aerospace, General Electric, Jet Engines, LEAP engine fuel nozzle. ADDITIVE MANUFACTURING: A YOUNG AND PROMISING TECHNOLOGY Every so often, a technology comes around that changes the shape of society and ushers the way for further advancements. The industrial revolution gave people an extensive supply of clothes, furniture, and other goods at a reasonable cost, sparking a culture of consumerism that has been growing for centuries. The internet revolution connected everyone and everywhere and we live in an age of unlimited information because of it. Today, one technology has engineers of all industries and backgrounds excited, and holds the potential to fundamentally change how parts are built and repaired. That technology is additive manufacturing (AM). AM—more commonly known as 3D printing—involves a continuous build; it successively adds material until an object is made. This is compared to the more traditional cutting and drilling of subtractive manufacturing, where a block of material is machined away until an object is formed. AM technology is relatively young; the early prototypes of 3D printers were developed just over 30 years ago. In 1987, the company 3D Systems released the first commercially available 3D printer, the SLA 1 [1]. In 1990, the first use of 3D printing for a metal part was a copper gear comprised of just 72 layers of laser-sintered powder [1]. Since these landmark foundations for AM, there have been decades of great interest, research, and investment into the technology. Today, due to very recent advancements in capabilities, there are far superior and more powerful machines and dozens of new AM processes. As a result, AM has become a credible alternative and sometimes even the preferred manufacturing method across a wide range of industries. Indeed, the past few years have seen the greatest growth in AM history. According to the Wohlers Report 2016, the AM industry grew 25.9% to a total of $5.165 billion in 2015 and the sales of AM systems for manufacturing metal parts grew at a year-on-year rate of 46.9% [3]. This clearly reflects a greater interest and acceptance of the manufacturing community for AM as a viable technique. This rising interest in AM is due to its compelling benefits. According to Suman Das of Georgia Tech, “Immediate near-term impacts [of AM] include dramatic ENGR0011/0711 Section