Chicago -Whether you design in plastic, metal, ceramics or all three, the National Design Engineering Show (NDES) had a material for you.
BF Goodrich Performance Materials promoted the latest products from its Specialty Plastics business. The company's newly expanded molding portfolio now addresses an even wider performance reach. Estane thermoplastic urethanes, for example, range from 70 A to 80 D shore hardness. And Estaloc RETP grades span from 50,000 to over 1 million psi. According to senior marketing manager Elliot Pritikin, these materials "provide design freedom and process versatility for overmolding as they are inherently compatible."
E-A-R Specialty Composites showed new VersaDamp damping and isolation materials. Formulations for these thermoplastic elastomers can be adjusted with respect to the desired damping properties or durometer. VersaDamp materials feature a durometer range from 35 Shore A to 75 Shore A. Their energy-absorption capabilities also span a wide range with peak loss factors from 0.75 to 0.15. Applications for these injection-moldable materials include anti-shock and anti-vibration mounts for compact devices with limited isolator sway space.
Rogers Corp. High Performance Elastomers, Poron Materials Unit exhibited two product lines at the show: BISCO cellular silicone foams and PORON cellular urethane foams. Available in rolls, these materials address a variety of gasketing, cushioning, and sealing problems. Test-rated materials are available for use in specific types of equipment, including electronic and electrical household appliances, office machines, and automotive equipment.
DSM Engineering Plastic Products showcased its full range of engineering-plastic stock shapes, including new high-performance ones made from Torlon PAI. The stock shapes come in two grades: Torlon 5030 is a glass-fiber-reinforced grade, and Torlon 7130 is reinforced with graphite fibers. Both materials "bridge the gap" between short-fiber-reinforced plastics and more costly continuous-fiber-reinforced plastics, particularly at elevated temperatures, reports Product Engineer Edward Alvarez.
Phillips Plastics Corporation showed its broad plastic and metal injection molding capabilities. In plastics, the company is focusing on soft-touch and other multi-shot applications that span a variety of materials as well as functional and aesthetic requirements.
NuSil Technology featured B-Stage, a silicone elastomer laminating adhesive available in sheet form for use in RFI/GFI gasketing, thermal and electrical interfacing, and solar cell bonding. It's available in optically clear, transparent, and thermally- and electrically-conductive sheets-all of which can be cured at room temperature or with heat. B-Stage materials can withstand thermal cycles from 115 to 260C.
Saint-Gobain Performance Plastics, formerly known as Norton Performance Plastics, showed a new solid acrylic tape to replace mechanical fasteners. Called Norcryl, it comes in clear and translucent configurations, making for neater application at exposed seams.
Carpenter Technology demonstrated its capabilities in engineered materials and in producing complex parts, and showed specialty products: ferrous-based alloys, titanium-tungsten-carbide ceramics, and injection molded parts.
Apple Rubber Products kicked off its new interactive, online design guide, which can be found on the web at www. applerubber.com. Its 14 sections guide engineers to sealing solutions with information on o-ring sizing, environmental considerations, material choice, troubleshooting, and more.
Solvay Polymers Inc. featured a high-density-polyethylene intended specifically for telecommunications conduit. Called Fortiflex HDPE TC46-25, it has a density of 0.946, a 0.25 melt index, and an ESCR greater than 2,000.
Ceramics can surprise
Chicago -Plenty of engineers know that ceramic components can
resist wear, corrosion, and thermal extremes. And their beneficial
electrical properties are no secret either. Indeed, for many applications,
ceramics have come to be the material of last resort once metals or
plastics have been found deficient.
So what's left to know? A lot, according to Frank Gorman, general
manager of advanced ceramics for AstroMet at the National Design
Engineering Show (NDES).
For one thing, ceramics still suffer from a shattering image problem:
"Knock a teacup off your desk and it shatters," Gorman says. "That's the
image many engineers have of ceramics."
But what he calls the "teacup syndrome" just doesn't jibe with the true
capabilities of these materials today. "We have ceramics nearly as tough
and ductile as metal," continues Gorman, a mechanical engineer with 27
years ceramics experience.
Some zirconia-based ceramics, for example, go up to eight on the
fracture toughness scale. In fact, AstroMet demonstrated a ceramic-headed,
steel-driving sledgehammer at the show. After three years of use, there's
nary a scratch on it, Gorman reports.
Another important thing to recognize is that ceramic offers rather
flexible tolerancing capabilities-and some limitations too. "One thing
that surprises engineers is that ceramic components can be made to
exceedingly tight tolerances-everything from fifty millionths of an inch
to relaxed tolerances of fifteen thousandths," Gorman says.
Of course, once you get below 0.005 inch typically there's a need for
finish grinding, which adds value of tight tolerances costs that typically
exceed those for metal grinding. Yet for those who truly need hardy parts,
Gorman points out the bright side of grinding. "Yeah, it costs us more to
grind, but that tells you how hard and wear resistant the material
One last thing to understand about ceramics is its diversity. Gorman
points out that advanced ceramic components represent just a small
fraction of a varied group that includes coatings, insulating materials,