The 3D printing market is expected to quadruple over the next decade to $12 billion, moving from its main use today of creating prototypes to the most complex of production parts, according to Lux Research. 3D printing, which has been around for 30 years, has mainly been used to create product prototypes. That's because product designs are easily manipulated in computer-aided design (CAD) software before being sent off to a printer.