|Among a number of new methods for creating prototypes quickly is the Zcast process, which involves printing a mold on a 3-D printer and pouring metal directly into the mold, producing parts like the manifold above.|
Rapid prototyping continues to be a growth industry. Terry Wohlers of Wohlers Assoc. Inc. reported at the Rapid Prototyping & Mfg. 2002 conference and trade show in April that 2001 saw more systems installed, more material consumed, and more applications for the technology uncovered. Yet, in spite of this activity, revenues for 2001 showed different numbers.
"An almost unbelievable number of new technologies, materials, and enhancements are under development in corporate, university, and government laboratories around the world," Wohlers says. However, he adds, "Revenues from products and services were down significantly and machine unit sales were flat."
Wohlers believes that the contrast of growth in part production to the stagnation of system sales is in part due to equipment and material enhancements. "These improvements offer higher throughput from the same number of systems," he says. "Other factors include improved capacity utilization and the growth in the concept modeling segment of the industry."
Although RP and RT technologies would seem to be a natural niche for mold shops and molding companies to adopt to expand capabilities, it hasn't caught on substantially in this group. "Moldmakers tend to be slow to adopt new technologies," Wohlers says.
For example, Wohlers pointed to spiral conformal cooling in molds to improve cycles by more than 30 to 40 percent, which can be achieved using a new method from Solidica. (See "Prototyping Makes Noise With Ultrasonic Fusion Process," June 2002 IMM, p. 52 for a full report.) Other new technologies include ProMetal's new R2-64 that operates like an inkjet printer to lay down material with a 40 percent bronze infiltrant; DMD 5000 from POM, which offers the ability to build large parts; RSP Tooling's Rapid Solidification Process; and EOS's Direct Metal laser sintering process, which builds complex geometries in 20-Âµm layers.
"Some molds come right out of the machine ready to mold parts if you need a matte finish," says Wohlers of the EOS process. "The hybrid approach means it may make sense to produce the cavity side of the mold using conventional CNC machining technology and the core side using an unconventional approach such as laser sintering. The core side is often the most difficult and time consuming of the two, so the benefits can be realized by building both sides in parallel."
Two new casting methods are being developed as well. Z Corp. is offering the Zcast process for making investment casting shells of a plastic/ceramic composite using MIT's 3DP technology. The other method, for creating aluminum castings, is also in development by a number of companies, and can produce a casting in one to two days.
Wohlers says that 166 new patents were filed in 2001 for RP/RT processes, and some 75 to 100 universities are doing work in RP. "RP has gone from dramatic change to incremental change, but I think we're seeing only the tip of the iceberg. It's my belief that RP and RT will grow exponentially. There are many exciting developments ahead."
Wohlers' Rapid Prototyping Report 2002 is available for purchase. For more information, see www.wohlersassociates.com.
Solidica Inc., Ann Arbor, MI
ProMetal Div., Extrude Hone Corp.
The POM Group Inc.,
Auburn Hills, MI
RSP Tooling LLC, Solon, OH
EOS GmbH, Munich, Germany
Z Corp., Burlington, MA