Transportation

A laser powder forming process called Laser Additive Manufacturing (LAM) was in development for seven years by AeroMet Corp. Parent company, MTS Systems Corp. shuttered the effort in Oct., 2005. The process was aimed directly at fabricating large metal parts for the aerospace market. Major cost savings were said to be realized both from the speed of near net shape fabrication and from waste material savings. Unlike subtractive processes, it isn't necessary to turn much of an expensive titanium billet into chips to make a part. Similar laser powder forming processes are under development by a number of other companies and laboratories which can also be applied to aerospace applications, however. LAM technology might also be purchased and developed further by another company.

A major area of interest is in the application of additive manufacturing technology to the fabrication of jet engine components. For example, turbine blades have complex shapes and must meet extremely stringent specifications. Several methods of using additive fabrication to make high-strength blades with single crystal structures are being investigated. Direct write technology can be used to improve blade finishes and for repair, and laser powder forming technologies for fabricating sensors within blades.

    

Other aerospace applications range from the mundane to near science fiction: Wind tunnel models can easily cost $100,000 and some detailed ones cost as much as a $1 million. This has been providing quite a bit of motivation to improve the fabrication process using additive technology. Additive fabrication is also being applied to the manufacture of composites for aerospace use. More on this subject can be found in the section on advanced materials. Long-term applications include active skin materials for drag reduction, and spare part manufacturing for space missions.

Marine
Marine applications of rapid manufacturing have some aspects in common with those for aerospace, and others with those for architectural construction. From the early days of rapid prototyping, it's been a goal to provide spare parts for naval vessels at sea. Early RP efforts in weld deposition were at least in part driven by this application, although laser powder forming technologies have lately received the most attention.

Like aircraft, watercraft are also manufactured in relatively small numbers and use parts that can be geometrically complicated. Although the parts are still costly, marine applications are not quite at the same lofty high value-added level as aircraft. Nevertheless, this segment still offers significant long-term possibilities, although it may not be quite the market-propelling force that aerospace applications have been.

Composite materials figure prominently in additive technologies being considered for making entire hulls and other large marine structures. Ernest Schroeder's patent application [5] describes the use of an extrusion forming method using fiber reinforced materials. It's similar to Contour Crafting or a humongous version of fused deposition modeling. Contour Crafting is under development for architectural construction and is described in that section. More information can be found about composites in the materials section.

Special tooling techniques for large structures are also being developed which could be complementary to this work. Surface Generation Ltd's (UK) Subtractive Pin Tooling (TM) (SPT) technology offers a method of making large tools while minimizing machining and material use. It may be possible to use such tools as forms for additive fabrication of the parts themselves.