Ice cream. Molecules for medicine. Even human skin. The list of what materials are used in 3D printing grows longer—and much more interesting—by the day. And expanding it is a multibillion-dollar material arms race right now.

A recently released 3D-printing market study found that the worldwide market for 3D-printing products was valued at $12.6 billion in 2020 and was expected to grow to $37.2 billion by 2036. That means a huge increase in the materials those machines use.

Plastic still reigns supreme in the 3D printing. According to a Grand View Research report, the market size for 3D printing plastics globally was valued at $638.7 million in 2020 and was expected to grow to $2.83 billion by 2027.

This material isn’t just your “everyday” plastic. Two types of plastic are most commonly used in 3D printing:

But it doesn’t stop there in the 3D-printing materials world.

Used for: Ready-to-install parts, finished products, prototypes

If there is a runner-up to plastic, it would be metal. Direct metal laser sintering (DMLS) is the technique and, unlike printing plastics, it can be used to make either a finished industrial product or a prototype. The aviation industry is already an early proponent and consumer of DMLS printing to streamline operations and manufacture ready-to-install parts. There are even already mass-market DMLS printers for creating 3D-printed jewelry.

The growth and popularity of 3D printing metals holds the potential to manufacture and create more effective machine parts that currently cannot be mass-produced onsite. This could lead to better conductors, tensile strength, and other attributes of laboratory metals than “mined-and-refined” metals such as steel and copper.

In the aerospace industry, the materials question is largely answered, and creating volume of parts is the Holy Grail. GE Aviation began printing fuel nozzles for its LEAP jet engine in 2016, ramping up to 30,000 parts in less than three years and printing its 100,000th nozzle in 2021. The LEAP’s successor, the RISE, will also incorporate 3D-printed parts.

Used for: Electronics, lighting

Australian-listed graphite and nickel miner Kibaran Resources has partnered with 3D-printing company 3D Group to share development costs on a research-and-development venture called 3D Graphtech Industries.

The partnership is pursuing patents to investigate 3D printing graphite and graphene, a pure form of carbon first created in a laboratory in 2004. Graphene conducts electricity better and is stronger, easier to insulate, and lighter than other conductors on the market today. It outperforms even the best conductors several times over. Because it must be created in a lab, it is a good case study for just what kind of mass production of metals additive manufacturing can accomplish.

Materials for research and development are sourced from Kibaran’s Tanzanian mines, where graphite with high crystallinity and a purity of 99.9% carbon has been found. This is incredibly well-suited to the production of graphene.

The semiconductor industry is interested in producing large quantities of graphene, as well. For example, IBM found a way to use it for LED lighting in 2014. The ability to 3D print sheets of material for use in LEDs could seriously cut lighting production costs.

Used for: Bearings, parts, electrical cable installation

Related to graphite, carbon fiber (which undergoes an oxidation process that stretches the polymer) can be added to the more traditional plastic to create a composite that can be as strong as steel but less intensive to use than aluminum, says Markforged. The company’s large-format 3D printers are designed to print stronger parts more quickly and at significantly lower costs.

Meanwhile, startup Impossible Objects has also been exploring carbon fiber, as well as glass, Kevlar, and fiberglass. The company’s printer can also work with PEEK (polyether ether ketone) thermoplastic polymers, which are typically used for bearings, piston parts, and electrical cable installation.

The 3D-printing industry is experimenting with a wide variety of innovative, novel approaches such a bio-based resins made from corn and soybean oil, powders, nitinol, and even paper.

As the list of materials grows, what does this mean for the actual hardware? Right now, on the consumer level, plastic is about as good as it gets. For example, the $1,399 Dremel 3D40 Flex is limited to PLA.

Today, several printers are focused entirely on DMLS, including the 3DSystems DMP Flex 350 and several models from Stratasys, but these currently cost upward of $100,000 each because DMLS printers burn much hotter than their plastic counterparts, as the powders and metals they create have higher melting points. Stronger housings and more powerful industrial smelting tools increase their costs significantly.

Although many 3D-printer manufacturers are offering metal 3D-printing services, it will be some time before the economies of scale that helped bring down the cost of plastic 3D printing affect the DMLS market. And 3D-printing systems with graphite/carbon fiber are just now starting to gain traction in the marketplace.

The diversity of applications that industries are exploring for 3D printing makes for an exciting but tumultuous time. From jet parts to lighting to rapid prototyping, the new (and “old”) 3D printing materials will deliver even more opportunities for how and what industries print.

This article has been updated. It was originally published in November 2014.