Calculated by cost, LPM metal 3D printing technology, metal radiators, engine cylinders, and oil pump casings are 5 to 10 times cheaper than manufacturing by powder bed molten metal 3D printing.
3D printing giant Stratasys revealed more details of the layered powder metallurgy (LPM) technology currently under development at Formnext 2018. The process was first made public earlier this year and is currently being developed to increase the speed, cost and facilities of 3D printing metal parts to meet the needs of short-term applications.
The LPM process utilizes powder metallurgy (PM) and unique binder methods to increase the efficiency of short-term metal parts production in terms of operation and cost. The technology has been developed at Stratasys for many years, is based on the company's proprietary PolyJet spray technology, and uses ready-made metallurgical powders.
As Stratasys revealed on Formnext, LPM technology uses a three-step process (dispensing and rolling, compacting, and printing). The process begins by dispensing the metal powder and then uniformly dispersing the metal powder into layers. From there, the metal powder layer is subjected to compaction, which results in a dense thin layer of metal powder. Next, a single shot deposits proprietary thermal ink onto the metal powder layer to define the geometry of the part.
These three steps are repeated layer by layer until a part or series of parts are built. Once the printing process is complete, the tray undergoes a cold isostatic pressing stage to increase the density of the parts by up to 99%. The tray is then dewaxed and the print boundaries are evaporated to facilitate the removal of metal parts from the build tray. Stratasys also emphasized that its support removal process allows users to get rid of support in minutes without processing. The final step is to sinter the metal part to burn off the adhesive, forming a dense metal part.
Because the LPM process relies on metallurgical metals rather than AM's specialized metal powders, production costs can be kept low. This technology is aimed at companies and manufacturers who need to produce pilot series parts, small-scale production during product upgrades and scrap, and custom, lightweight, and complex parts. The main industries that Stratasys is targeting with its LPM process are automotive, aerospace and defense.
"We noticed that the current methods of 3D printing metal parts have many shortcomings-including slow post-processing, elaborate support disassembly, and hours of matching and grinding," said Rafie Grinvald, director of product marketing and management at Stratasys. "Combined with the high cost of AM powder, this means that every part is expensive."
Grinvald continued: "Our new platform is designed to change the current field of metal additive manufacturing-providing a viable alternative to typical production methods-and helping our customers significantly reduce the cost application of reliable, consistent production-grade metal parts for short-term production."
Although LPM technology is not yet available, Stratasys has revealed that it is currently engaged in closed-loop feedback discussions with OEMs and Tier-1 to advance the process. Additional details on the technical specifications and release date will be announced shortly.