3D laser printing has entered the mainstream with everyone from students, to artists, to small businesses jumping on the 3D laser printing bandwagon. Though for many of us the technology is relatively new, 3D laser printing or "additive manufacturing", as it is also known, began in the 70s and 80s, with the efforts of scientists and grad students to find a way to more efficiently and economically manufacture goods on a small scale.
The core manufacturing processes - casting/molding, forming, joining and machining - have not been replaced by 3D printing, as one might speculate, but have simply been scaled down through the adaption of new techniques in manufacturing. New techniques for solid modeling have allowed researchers to translate 3-D geometries into mathematical terms, which in turn enabled them to become the instructions for equipment control systems.
As additive manufacturing has evolved, taking on new processes and advances in solid manufacturing, the technology has expanded to supporting rapid fabrication from digital models or templates and a range of geometries that surpasses the capabilities of other methods.
The lion's share of the additive manufacturing techniques that make up the foundations of the technology were invented and patented in the 80s. To better understand 3D laser printing today, let's review some of the components that led to creating it. To begin with, "additive manufacturing", simply put, is a process of making something three dimensional by literally layering materials upon each other following a digital design or template. What follows is a brief overview of some of the original 3D printing or additive manufacturing techniques and processes:
Stereolithography, sometimes called vat photopolymerization, is an additive manufacturing process that uses resins and lasers to build 3D objects. Selective laser sintering (SLS), also known as powder bed fusion, uses a computer-controlled laser (e.g., a sealed off CO2 laser) to selectively "sinter," or fuse, cross-sections of powder into a solid. Sheet lamination, also known as laminated object manufacturing, is the process of cutting a thin sheet of paper, plastic or metal into a desired shape with a laser, repeating this and bonding each layer upon the previous one. Material extrusion works by pushing liquid plastic or metal out through a nozzle, following a path on a digital map. 3-D printing, also known as binder jetting, involves repeatedly laying down layers of powder and then squirting liquid binder on the areas to be solidified to construct 3-D objects.
There a number of companies providing SLM technology, such as Coherent, because of SLM's ability to enable highly accurate, smooth, and consistent components with a wide range of materials., which has led to their utilization by a variety of industries, such as, automotive design, heavy equipment, aerospace, defense, medical, electronics and consumer products and government research.
In a recent article of Phys.org, Steve McKnight, director of the NSF Division of Civil, Mechanical, and Manufacturing Innovation, was quoted as saying, "To realize the full promise of additive manufacturing, researchers will need to discover new ways to increase speed, lower costs, improve consistency and develop and qualify novel materials for all kinds of applications. It will take the ingenuity of engineers, students and makers."
For more information on SLS technology and products, visit: http://www.coherent.com/applications/index.cfm?fuseaction=Forms.page&PageID=314.
Mark Williams is the author of this article about laser sintering and the science behind 3D printing. He has gathered from a variety of sources including Coherent laser manufacturer to write this article.