After 30-plus years of photopolymers being the most-used material in AM, polyamide (nylon) has finally caught up, Wohlers noted. Photopolymers, he said, have been used primarily for models and prototype parts. But with powder-bed fusion gaining traction as an AM process, companies increasingly are 3D printing commercial parts, and for those applications durable, well-understood nylon is often a material of choice.
When it comes to 3D printed metals, titanium has traditionally been the most-used material, but in the past year it was surpassed by aluminum as the most popular. Until just a few years ago, it was difficult to find a high-quality aluminum for additive manufacturing, Wohlers said, but now many aluminum alloys have been developed, and they are less expensive than many metal alternatives.
Wohlers Associates asked companies how much 3D printing use had grown within their company for production applications. They received data from hundreds of companies, which reported that, on average, their use for production grew by 23.9 percent in 2020 vs. the prior year.
There could be many reasons for this, Wohlers noted, including increased confidence in the process, the availability of more standards, and the growing recognition of the need to design for additive manufacturing (DfAM). “If you simply design as you always have for conventional manufacturing, whether it’s molding, casting, or machining, it almost always works against additive manufacturing,” he said. “It just doesn’t add up.”
By employing DfAM, one can often realize part consolidation and topology optimization, leading to lower weight and a reduced use of material. Being able to reduce the use of often-expensive support material, especially with metals, is also a key AM benefit, saving on material and labor costs, as well as time.
“You can design in ways to reduce the support material to a minimum, and turn it into permanent features,” Wohlers said. “It can be a showstopper if you don’t consider methods of DfAM.”