Green Technology Forum

Leading suppliers of materials for rapid prototyping and rapid manufacturing are finding that nanoparticles can dramatically alter the properties of finished components. Paul Stevens looks at what is available on the market and how another nanotechnology-based process is enhancing the properties of parts built from standard materials.

Nanotechnology is now finding applications in numerous consumer products, ranging from sunscreen and cosmetics to sporting goods and guitar strings. In the field of rapid prototyping and rapid manufacturing, nanotechnology is also now offering advantages to new product development teams.

In this article we will look at materials for tooling and model building, as well as an innovative technology that improves the performance of standard materials used for rapid prototyping and rapid manufacturing.

Heavily filled with non-crystalline nanoparticles, Nanotool resin is one of the Protocomposite materials available from DSM Somos. When cured, it is a ceramic-like material with a flexural modulus of 10,500 MPa, a heat deflection temperature of 260˚C (at 0.46 MPa after thermal post-cure), a Shore D hardness of 94 and very low linear shrinkage.

DSM Somos says the resin also offers excellent side wall quality, which reduces the amount of finishing time required and makes it attractive for applications that requiring highly finished parts. As well as being suitable for rapid tooling used in injection moulding applications, Nanotool is also suitable for the production of high-quality models for wind tunnel testing and parts that can be metal-plated as prototypes for cast metal components.

Nanotool can be used with the stereolithography process to create tooling inserts capable of moulding hundreds or, in some cases, thousands of parts from thermoplastics such as polyethylene, polypropylene, thermoplastic elastomers, high-impact polystyrene, ABS, polycarbonate and glass-filled nylon. These moulded parts would typically be used for performance testing or marketing studies, though the quality and structural integrity of the parts mean that they can also be suitable as production parts for short-run applications, provided the relatively long moulding cycle time of 60–120 s is acceptable. For tooling that would traditionally require extensive electro-discharge machining, the rapid tooling process is likely to be more cost-effective than machined metal tooling. In addition, turnaround times can be very short, with moulded parts available in as little as three to five days.

As a guideline, DSM Somos suggests that Nanotool should be used for components up to approximately 100 mm in size with ribs no less than 1.6 mm thick due to the relatively brittle nature of the material. A minimum draft angle of 2 degrees is recommended and, although sharp corners can be produced, the company cautions that this can reduce the life of the tool. For complex components, hand loaded cores can be used, and metal inserts remain an option for tall or thin-walled features that would be difficult to tool in Nanotool.

source: engineerlive.com

This entry was posted on Thursday, March 6th, 2008 at 7:20 am and is filed under Design, Materials, Nanotechnology, News, Products. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.