Even though the U.S. economy is the largest in the world by GDP, it was a crisis in the manufacturing sector that prompted the government to act to save the industrial sector over the last decade. On the face of it, the U.S. manufacturing sector accounts for 11.6 percent of GDP, employs over 12 million people and makes up two-thirds of all exports. Look below the surface, however, and the economy hasn't always been as healthy.

Plastic injection molding, metal casting and metal stamping are age-old processes that form the backbone of manufacturing. Traditionally, there's no better way to mass-produce plastic or metal parts. However, additive manufacturing, which enables engineers to consolidate parts and produce components in complex shapes, is quickly becoming an alternative. The technology is evolving from the world of low-volume prototypes to high-volume production-ready parts.