While this additive manufacturing process has proven an ideal technology for rapid building of metal parts—including core and cavity inserts for molds—it hasn't caught on with many moldmakers.
Elsewhere, Direct Metal Laser Sintering (DMLS) is an additive manufacturing process that is catching on big in many applications, specifically for end-use parts. While it might be a disruptive technology for core and cavity inserts for injection molds for prototype and short run production purposes, DMLS has yet to find its place among moldmakers in those applications. Where it has become beneficial to moldmakers is in the area of conformal cooling channels, which has been quite a successful application.
|Morris Technologies added a EOSINT M-280 laser sintering system in 2010.|
DMLS was developed by the German firm, EOS, a global provider of laser-sintering systems for e-Manufacturing. The technology manufactures parts for every phase of the product life cycle, directly from electronic data, accelerating product development and optimizing production processes. It also facilitates mass customization, a production process that was only an idea less than two decades ago.Today, that's an attainable business strategy.
Greg Morris, CEO of Morris Technologies Inc. (MTI) acknowledges that while some core and cavity insert work is being done using DMLS, the bulk of the projects involves direct parts. "There are a huge number of direct parts being manufactured using DMLS," Morris told PlasticsToday in a recent interview.
MTI was one of the first shops in the U.S. to collaborate closely with major aerospace and medical OEMs to explore laser-sintering. Now, the company is close to certifying laser-sintered metals in both fields and making a variety of end-use components for everything from lightweight parts for military unmanned aerial vehicles (UAVs) to gas turbine engine components to cobalt-chrome hip replacement implants for patients of the future.
When asked why there isn't more core/cavity insert work being done with the technology, Morris replied, "My sense is that it's a combination of things including resistance of U.S.-based companies to use this technology and to locate that sweet spot of the benefits of DMLS inserts vs. traditional machining methods."
Catching on in Europe, conformal cooling
However, Morris said it's an "ongoing" discussion in the moldmaking industry. "The interest level seems to be with the benefits of conformal cooling in reducing cycle time in molds, but it's geometry dependent, which means you have to pick the right project," he explains. "There's a bit of a disconnect between the mold community and what the DMLS technology can do. The Europeans seemed to have adopted and embraced DMLS for conformal cooling to reduce cycle times, but U.S. moldmakers have not for the most part."
While DMLS might be seen as a disruptive technology in some ways to machining and fabricating, and even injection moldmaking/molding, DMLS is also a complementary technology to machining and fabricating. Morris explains that DMLS parts typically require some post machining to get a specific tolerance or surface finish. "You can make a very convincing case that DMLS is disruptive, if you can't make a part any other way," he notes.
For example, Morris can take a traditional design in the aerospace industry and reduce the weight, which reduces the fuel consumption and over the life of the component can save a lot of money. "We've seen an explosion of interest from companies wanting end use parts in DMLS technology," adds Morris. "It's getting to a broader audience. The Fortune 100 companies are embracing this."
Additive manufacturing investments adding up
MTI and its sister company Rapid Quality Manufacturing (RQM) operate 20 DMLS systems spanning from the EOSINT M-250 to the newest system the EOSINT M-280, the most of any organization in the world, claims EOS, putting them at the forefront of OEMs and service bureaus in defining what can be made by "growing" custom parts. Additionally, MTI has several plastic additive manufacturing systems, including the Connex technology from Objet Geometries Ltd.
This year, Morris added EOS' newest generation DMLS system, the EOSINT M-280. This latest DMLS system offers a 400W laser that increases throughput and offers a larger Z axis with an increase of about 4 inches so that now up to 12.9 inches in the Z direction is available for taller parts. An updated chamber flow of gas provide a more even distribution of properties across the bed. MTI employs 115, including a staff of 20 design engineers.
"We believe strongly in the additive metals world," says Morris. "DMLS is a tool like any other technology, but happens to be - in our opinion - a very powerful tool that can incorporate high levels of complexity into the part. It's not the answer to every part, but where it fits it will have a dramatic effect, including the ability to change how a part functions and the cost, while also changing the design rules and how parts interact together."
Morris sees a bright future for all the additive processes. "They are an excellent tool for mass customization where it's impractical to make a tool and shoot one part - and be very cost effective doing it," he concludes.