Time to Update RP Materials?

Your mantra: “Faster time to market. Faster time to market.” Here are some materials that could change your chant to “Build better parts. Out the door today.”

Staying competitive can be tricky in this global marketplace. There are many companies trying to woo your business. Perhaps using a new or different rapid prototyping material can help you generate higher quality products, exceed your customers’ expectations, and grow your business.

duct-connect-tri-channel
This material has a low smoke density and toxicity, and emits no corrosive gases.

For instance, 3D Systems launched its DuraForm FR 100 material to meet the flame retardancy necessary for many potential aerospace applications. It has been formulated to reduce production of smoke and related toxic byproducts of combustion and achieve UL94 V-0 rating to meet the needs of today’s human environmental safety for many other consumer applications.

The product is well suited for injection molded plastics. You can build prototypes that withstand functional testing. You can also produce durable end-use parts without tooling, create accurate and repeatable custom parts, and possibly increase your market opportunities through plane retardancy.

The material is flame retardant and halogen and antimony free. It is FAR 25.853 non-drip and UL94 V-0 compliant, and has low smoke density and toxicity. According to 3S Systems, the product is easy to process, emits no corrosive gases, and meets aerospace smoke density and toxicity requirements.


DuraForm FR 100 is flame retardant and is ideal for generating prototype parts for testing such as these computer mouse components.

Some DuraForm Fr 100 applications include rapid manufacturing, aerospace and aircraft cabins, computers and business equipment, complex thin-walled ductwork, housings and enclosures, automotive components, and consumer goods and sporting equipment.

3D Systems
www.3dsystems.com



RP Materials

Resins
Epoxies Etc. announced its 70-2170 urethane casting resin as a liquid, low viscosity material for casting dimensionally stable parts. Parts made with the material have an acrylonitrile butadiene styrene (ABS) feel and appearance. The product is mercury free and does not contain TDI or 4,4-methylenebis (2-chloroaniline) (MbOCA). According to the company, the material’s low shrinkage and low viscosity facilitates the production of precision parts.

Part-made-with-70-2170-resin
Part made with 70-2170 being removed from a metal mold.

The prototyping material offers the following properties:

• High impact resistance
• Dimensional stablility
• Fast room temperature cure
• High durometer
• Convenient mix ration
• Good machinability

The resin has a tensile strength of 7,200 psi, a hardness rate of 70 Shore D, an Izod impact strength of 1.57-ft/lb/in., and a glass transition temperature of 78°C.

Another resin material that may suit your needs is the Spectar copolyester sheet product. It comes in sheet sizes of 3/8-in. and ½-in. thicknesses for use in the medical device market. The product is available in 4-ft X 8-ft sizes off the floor; 8-in. X 10-in. hand samples are also available. Material manufacturer Spartech says the product is highly chemical resistant and non-corrosive making it a good choice for thermoforming orthopedic casts, chest protectors, neck braces, and nursery isolettes. The product is recyclable. Overages and trim can be reground and reprocessed into other non-medical products.

Specter copolyester is a thermoplastic sheet used in engineering applications and can produce complex shapes, precise details, deep draws, and compound curves without worrying about durability. It is easily formed, die-cut, and punched. The product passed ISO 10993 biocompatibility testing.

Also fairly new to the market is a resin from Ticona called Fortron 6162A7. It’s a mineral/glass-filled polyphenylene sulfide (PPS) with good flow properties for appliance, industrial, and electrical/electronic applications that require high-temperature resistant, thin-wall components.

The material is flame resistant without additives and is recognized by Underwriters Laboratories to be UL 94 V-0 for wall thicknesses down to 0.8 mm. Other features include the following:
• It has a 40% improved flow versus Fortran 6165A6.
• The Comparative Tracking Index (CTI) is greater than or equal to 175 volts.
• It rates 0 UL hot wire ignition (HWI) at 3.0 mm thickness.

The material manufacturer developed the new product in direct response to a consumer appliance maker that needed a higher-flow material to mold larger diameter parts in a multi-cavity tool. The molding conditions required an enhanced Fortron PPS grade with improved flow that could maintain the same shrinkage properties and has all the properties of the original product.

Gulfstream-G650-rudder
Ticona developed Fortron 6162A7 for an appliance customer that needed a higher-flow material to mold larger diameter parts in a multi-cavity tool.

The material is well suited for industrial and appliance applications such as induction heating coil plates for food warmers and electric ranges, and laboratory “cool touch” heating apparatus. The company says the product is for use in electric switches, relays, potentiometers, and other circuit carrying components.

Epoxies Etc.
www.epoxies.com

Spartech
www.spartech.com

Ticona
www.ticona.com


Elastomers
New medical elastomers for tubing perform like PVC and can provide better gamma stability. Teknor Apex announced a series of advanced medical-grade elastomers as an alternative to PVC for many tubing applications. The New Medalist MD-500 Series compounds exhibit crystal clarity and mechanical properties comparable to those of PVC. The company claims the materials provide similar clamp resilience and resistance to kinking and necking.

The products undergo minimal color shift upon heat aging after exposure to gamma irradiation, the most severe type of sterilization. A typical compound in the series Medalist MD-575 exhibits 70% less heat-aged color shift than a gamma-stabilized PVC compound of comparable hardness.

Medalist MD-500 Series elastomers have been tested for compliance with ISO 10993-5 cytotoxicity standards and are free of animal-derived materials, phthalates, latex, silicones, and additives not directly required for medical applications. Standard formulations include five grades, with Shore A hardness (15 sec.) ranging from 53 to 86.

Medalist-MD-500-series-elastomers

The Medalist program for medical manufacturers includes 30 standard high-purity elastomer compounds with a test data and resources for designers and processors. Compounds are available with Shore A hardness from 5 to 87 and include clear, translucent, and opaque formulations.

Teknor Apex
www.teknorapex.com

 


Materials for fused deposition modeling (FDM)
In this issue and subsequent DMR supplements, we will provide information about materials suitable for various rapid prototyping processes. The first is acrylonitrile butadiene styrene (ABS) which is a strong, durable production-grade thermoplastic that is used in many industries. It is often used for conceptual prototyping through design verification through direct digital manufacturing. The marriage of ABS with FDM technology gives you the ability to create parts from digital files in a variety of standard and custom colors.

This material is suited for the rapid prototype production, tooling, and tool-less manufacture of production parts. It is also used in applications where impact-resistance and structural strength are necessary. It is accurate, durable, and robust enough for field testing or demonstration units. Because of its dimensional stability, it is suited for pre-production rapid prototypes that can accurately predict performance of injection molded parts.

Applications that can benefit from the use of ABS include:

• Concept modeling
• Form, fit, function
• Design verification
• Master for RTV molding and vacuum forming
• Jigs and fixtures
• Marketing tools
• Thermoforming

Parts generated using ABS are produced within an accuracy of +/- 0.005-in. or +/- 0.0015-in./in. whichever is greater (+/- 0.127 mm or +/- 0.00015 mm/mm whichever is greater. Maximum build dimensions are 23.6 X 19.7 X 23.6-in. and 600 X 500 X 600-mm.

 


Polyphenylsulfone (PPSF)
PPSF is suited for aerospace, automotive, and medical applications. FDM systems manufacture parts using this material expect mechanically superior parts and dimensionally accurate specifications. You can also sterilize PPFS parts using a steam autoclave, EtO sterilization, plasma sterilization, chemical sterilization, and radiation.

The material is said to be a high performance, heat and chemical resistant product. It uses a break-away support structure. These supports have to be manually removed. Because of this requirement, some geometries and features will have support structures that are difficult to remove.

Parts are produced within an accuracy of +/- 0.005/in. or +/- 0.0015-in./in. whichever is greater (+/- 0.127-mm or +/- 0.0015-mm/mm whichever is greater). Maximum build dimensions are 16 X 14 X 16-in. and 406 X 355 X 406-mm.

MPF