Part Buyers Authority Issue #5

5 Visit partbuyersauthority.com to SUBSCRIBE o r CONTRIBUTE as an author. There are some truly amazing projects happening in the metal Additive Manufacturing (AM) space these days. 3D metal printing is serving a wide variety of critical industries including: aerospace, medical, heavy duty diesel, automotive, oil and gas and US Government/DOD. Our 3D printing focus is on Direct Metal Laser Sintering (DMLS) also known as Selective Laser Melting (SLM) and sometimes referred to as Powder Bed Fusion Technology. This digital process uses a layer by layer material build-up approach using layers of powdered metal from 20 to 100 micron. This digital process can produce high precision metal parts in a very short time versus traditional tooling and manufacturing methods. CHRIS BECK Manager of Operations/Co-Owner INNOVATIVE 3D MANUFACTURING METAL AM MISCONCEPTIONS Let’s clear the air on all misconceptions about part quality built by the DMLS process. On average part densities are 99.5% and DMLS parts have the same or very close to the same mechanical properties as bar stock. Most heat treat and stress relief cycles are the same. Parts can also be coated or plated just like other metal parts. Many AM builds come with both vertical and horizontal test bars. Material test plugs and loose material samples can be sent to approved labs for customer testing. All parts we produce also come with material certifications. High quality parts produced by the DMLS process are being used daily in critical mission applications in a broad range of demanding industries. WHAT PARTS MAKE THE MOST SENSE FOR THE METAL AM PROCESS Most of the DMLS machines on the market have a build chamber of 10”x10”x12” LXWXH. Powder to fill these machines is very expensive, on average it costs $30-$150 per pound. With this technology you can make any geometry that you would like. But you really need to take the time to look at the part and the part processing to see if it makes sense. Big and heavy parts are typically not good candidates for DMLS as they take too long to make and post process. The following is a list of common part challenges that tend to make ideal candidates for DMLS production:. • Material required – parts that are made from materials that traditionally take a long time to machine from solid billet; for example Inconel and Titanium alloys • Machining – parts with thin wall conditions that cannot be machined or casted • Complex geometries – such as lattice structures or internal features that cannot be made any other way • Small features – that take very small cutting tools to produce, tolerance dependent (+/- .005”) • Near net shapes – machining of ‘truly critical features’ • Off angle holes – that cause an additional machining operation or 5 axis CNC Machine. • Parts with overhanging features – that require lots of support structure • Full design freedom – including parts with fillets and rounds on all surfaces (no sharp corners) Continued on next page