Selective laser sintering

Selective laser sintering (SLS) emerged from Carl Deckard's undergraduate imagination at the University of Texas at Austin, where he conceived the idea of using a laser to fuse powdered material layer by layer into solid three-dimensional objects. Working with professor Joe Beaman, Deckard filed a patent application in October 1986 and built the first SLS machine—nicknamed 'Betsy'—by 1987. The technology became one of the foundational pillars of additive manufacturing.

Deckard came from a family of PhD holders, born during the Space Race in 1961. He visited the Henry Ford Museum around age eight and decided to become an inventor. When choosing a college major, he selected mechanical engineering because it was 'the closest thing to majoring in inventing.' His undergraduate insight—that a directed energy beam could selectively sinter powdered material—would create an industry.

The adjacent possible for SLS had opened through laser technology and computer-aided design. Carbon dioxide lasers provided the directed energy source. CAD systems could generate the cross-sectional slices needed to build objects layer by layer. Powder metallurgy offered understanding of how particles could be fused. What was missing was the integration: using a laser to trace patterns in powder beds, building objects from the bottom up.

Betsy, the first prototype (1984-1986), proved the concept's viability. A cube—the first product with recognizable complex 3D shape—was shown to the patent committee to demonstrate SLS's potential. Deckard, along with Paul McClure and entrepreneur Harold Blair, founded Nova Automation in 1986 to commercialize the technology. Nova became DTM in 1989—the first student/faculty-owned business spun out from UT Austin.

The cascade from SLS helped create the additive manufacturing industry. SLS proved particularly valuable for producing functional prototypes and end-use parts in engineering plastics and metals. Unlike stereolithography (which required liquid resins), SLS could work with a wide range of powdered materials. The technology found applications in aerospace, automotive, medical devices, and consumer products.

3D Systems acquired DTM for $45 million in 2001, integrating SLS into its portfolio of additive manufacturing technologies. Carl Deckard died on December 23, 2019 at age 58, remembered as 'a creative genius with so much more to contribute.' The undergraduate idea he conceived in Austin had grown into a manufacturing revolution, with SLS machines producing functional parts across industries worldwide.