The ExOne Company, based in North Huntington, Pennsylvania, USA, has qualified fifteen new metal, ceramic and composite materials for Binder Jet Additive Manufacturing on its machines, bringing the company’s total supported materials to twenty-one. Among the materials qualified by ExOne to date are ten single-alloy metals, six ceramics and five composite materials. Over twenty-four additional powders are also said to be approved for R&D environments, including aluminium and Inconel 718.
“From the outside, it may look like ExOne’s metal printers jumped from six to twenty-one qualified materials overnight. In reality, ExOne’s engineering team and our customers have been moving so fast to print new materials since 2013 – the breakthrough year when we began printing dense single-alloy metals – that we haven’t slowed down to update the market on our progress,” stated John F Hartner, ExOne CEO, in a further message following the announcement.
“When we took the time to re-evaluate where we were over the last few months, the numbers surprised even us,” he commented. “ExOne customers were printing an astonishing number of materials – fourteen – that had not yet worked all the way through ExOne’s rigorous qualification process. That included six single alloys, six ceramics, and two ceramic-metal composites.”
“At the same time, we were ready to announce new materials, such as M2 Tool Steel, had achieved our highest qualified status, and other materials, such as aluminium and titanium, were qualified for controlled R&D printing. So, a major reset was needed,” he stated.
Partners that have assisted ExOne in qualifying materials include Global Tungsten & Powders, H.C. Starck Solutions, NASA, Oak Ridge National Laboratory, SGL Carbon, the U.S. Army, the U.S. Department of Energy, the University of Texas at El Paso, and Virginia Tech.
New materials qualification system
As of February 25, 2020, ExOne reported that it has three material qualification levels that recognise different degrees of material readiness for customers with different application needs.
Third-party qualified materials
These materials have passed rigorous ExOne tests over multiple builds, and have verified material property data from an independent third party. Among the third-party qualified materials currently available are 17-4PH, 304L, 316L, M2 tool steel, and the metal composites 316 with bronze, 420 with bronze, and tungsten with bronze.
These materials have been qualified by ExOne customers with their own standards and are being successfully additively manufactured today for their own applications. Among the customer-qualified metals available are cobalt chrome, copper, H13 tool steel, Inconel 625, titanium, tungsten heavy alloy. Ceramics available include alumina, carbon, natural sand, synthetic sand, silicon carbide and tungsten carbide-cobalt. The ceramic-metal composites boron-carbide aluminum and silicon carbide with silicon are also available.
These materials have passed a preliminary qualification phase by ExOne and are deemed printable, supported by ongoing development. The twenty-six materials in this category include the metals 4140, 420, 4340, 4605, aluminium, bronze, H11 tool steel, Hastelloy, Haynes 230, Inconel 718, iron-chrome-aluminium, Panacea, tungsten and TZM Molybdenum, the ceramics aluminium nitride, barium titanate, boron carbide, glass, lead zirconate titanate (PZT), silicon nitride, tungsten carbide, zirconia and zirconium carbide, and metal composites including iron with bronze, tungsten with copper and tungsten with Invar.
ExOne stated that it believes the ability to additively manufacture some materials, such as aluminium, at high speeds, will have a transformative and sustainable effect on the automobile and aerospace industry. Rick Lucas, Chief Technology Officer at ExOne, explained, “While our teams can binder jet aluminium in controlled R&D environments today, we believe that optimising this material for high-speed 3D printing will eventually transform how car and air plane parts are made, making them smarter and lighter weight.”
“Based on high demand from the marketplace, we have fast-tracked development of this material for use on our machines,” he stated. To accelerate this work, ExOne is also collaborating with a number of manufacturing companies to optimise the commercial AM of aluminium.
“Qualifying a new material for binder jet 3D printing is complex work that involves optimising how materials, machines and processes work together. We would like to thank our customers and partners for their assistance in accelerating this important work, which is enabling more sustainable manufacturing and part designs,” concluded Hartner.
ExOne’s family of metal AM machines includes the Innovent+, an entry-level system used globally for R&D, design and small part production; the X1 25Pro, a mid-sized production AM machine that is large enough for most metal parts manufactured today; and the X1 160Pro, the company’s largest metal AM machine, slated for delivery later this year.