October 2007

CPS Offers AlSiC Metal Matrix Composite Base Plates for High Power, High Reliability
IGBT Modules

CPS Corp. offers AlSiC (Aluminum Silicon Carbide), a metal matrix composite well suited for base plates material for insulated gate bipolar transistor (IGBT) used in high-power traction, power control, hybrid electric vehicle power systems and fly-by-wire applications.  AlSiC has been tested and meets the requirements of the Restriction of Hazardous Substances Directive (RoHS compliant) of the European Parliament.

The low isotropic coefficient of thermal expansion (CTE) value of AlSiC-9 (8 ppm/°C: 30 to 100°C) is compatible with the thermal expansion value of the die or substrate used in I GBT applications.  The AlSiC CTE match reduces the mechanical stresses on IGBT die and substrates that are induced by thermal power cycling, which improved reliability of substrate attachment and reduces die cracking failures.  

The device compatible AlSiC CTE eliminates the need for stress compensation material layers that are required in Cu (CTE = 17ppm/°C) baseplate assemblies.  Elimination of stress compensation materials simplifies assembly and reduces the thermal resistance for AlSiC systems so that AlSiC systems have equal or improved thermal dissipation over Cu baseplate assemblies. 

In high power applications (> 1,200 V/ 400 A) I GBT modules assembled with AlSiC baseplates are found to have a service reliability of many 10s of thousands of thermal power cycles over Cu equivalent systems.

AlSiC is a lightweight material (1/3 that of Cu), which makes it a suitable cooler material for the weight-sensitive I GBT applications.  AlSiC also has higher strength and stiffness than Cu, which combined with its lightweight nature, makes AlSiC assemblies more tolerant shock and vibration.

The CPS AlSiC near net-shape fabrication process both produces the composite material and fabricates the product geometry, allowing for the design of I GBT base plates with a dome profile. This geometry improves thermal interface contact with cold plates and coolers, adding to AlSiC’s advanced thermal management qualities.  CPS fabricates standard of 190 mm by 140 mm, 140 mm by 130 mm and 140 mm by 70-mm base plate formats (shown) as well as custom formats.

ADMET Releases Low-Force, High-Speed eXpert 5607 Universal Testing Machine for
Dynamic Testing

ADMET Inc., a provider of integrated materials testing systems, has introduced a low-force, high-speed tabletop universal testing machine. Called the eXpert 5607, the tabletop machine performs compression, tensile and cyclic testing up to 1,000 grams maximum force. It features crosshead speeds of up to 350 inches per minute and is well suited for testing biomedical materials, plastics, textiles, etc.

Coupled with ADMET’s eP-DS (dynamic servo controller), the eXpert 5607 offers precise measurement of extremely low-force tests plus cyclic testing to 15 Hz. Users can program ramp, square and triangular waveforms. They can also adjust control gains and end point values on the fly or activate amplitude control so that the eP-DS automatically adjusts the end point values to ensure that the desired targets are met.

“The ADMET eXpert 5607 continues to deliver on our commitment to provide testing equipment that is optimized for emerging biomedical and plastics applications,” said Richard Gedney, ADMET founder and president. “Our easy-to-use yet flexible (in the good sense) and inexpensive compression, tensile and cyclic testing equipment gives researchers and manufacturers an efficient way to certify that their products meet customer requirements and industry standards.”

The eXpert 5607 is available immediately directly from ADMET and through ADMET representatives. Pricing for the eXpert 5607 with the eP-DS Digital Controller starts at $5,900.

Masterbatch Technology Utilized in New Long Fiber Compounds from RTP Company

RTP Company’s has extended its offering to include engineered long fiber thermoplastic (LFT) compounds with the introduction of long cut additives.  The long-cut masterbatches are available as cube blends with RTP Company’s line of LFT products.  Separation during handling is minimized because of similar pellet geometry allowing customers to receive superior,
economic LFTs.

“We are in a unique supply situation because of our ability to formulate and produce long-cut color and additive packages for our LFT business,” said Eric Lee, business manager of Structural Materials at RTP Company. “By applying our compounding competencies to long-cut additives for LFTs, we are able to create robust LFT solutions and minimize lead times for our customers.” 

Traditional LFT suppliers are restricted in how they deliver LFT products containing additives. With RTP Company’s masterbatch technology, customers are offered more choices; additives in long-cut masterbatch pellets for dry blending or additives in pre-compounded LFT pellets. As a privately owned firm, RTP Company has access to a wider breadth of additive technologies and can customize packages to meet specific end use requirements.

“Combining other technologies like custom colors, UV stabilization, wear resistance, or static dissipation with long fiber compounds is an underutilized advantage in the industry today,” said Karl Hoppe, RTP Company's lead development engineer for Long Fiber Compounds. “With our long-cut additives, customers can now incorporate these technologies at a lower cost compared to traditional LFT compounds.”

Metal replacement is the most common use for LFTs because of their excellent mechanical properties and high strength-to-weight ratios.  Other opportunities for innovative LFT applications continue to emerge, as RTP Company’s complimentary compounding technologies are cross-engineered into LFTs.  In addition to the new masterbatch LFT compounds, RTP Company has developed LFTs to compliment its thermoplastic elastomers (TPEs). The LFTs provide an improved bonding substrate for overmolding various TPE compounds in consumer good applications such as power tools and sporting goods.

Unifin Offers Cardinal Valves for Demanding Transformer Oil Applications

Unifin, a supplier of cooling equipment and transformer oil pumps and valves to the power generation and power transformer industries, offers its line of heavy-duty transformer oil valves, manufactured under the company’s Cardinal brand. Cardinal valves are the industry’s only valves that are specifically designed to meet the demanding requirements of transformer oil applications.

To perform reliably under extreme operating conditions, Cardinal valves are rated for temperatures ranging from –40ºC (–40ºF) to 100ºC (212ºF).  All parts are made from non-corrosive or a suitably protected material to withstand outdoor exposure on external surfaces and hot transformer oil on internal surfaces.

Cardinal valves are robust in design, so that over-tightening or minor abuse encountered in handling or during factory/field installation will not result in valve malfunction.  The fasteners are designed to prevent loosening under normal operating conditions.

The operating handle displays the valve’s open and shut position and can be manually locked in either position. 

Cardinal valves are designed for use on new transformers or as replacements on existing electrical transformers.  Cardinal valves are available in sizes ranging from 2 inches to 8 inches including ANSI standard and OEM-specific flange configurations.

Fabrico Launches New Web Site

Fabrico, a provider of design and manufacturing services for flexible materials, has launched a new web site at www.fabrico.com. The new web site highlights the company’s broad applications knowledge and details the materials and equipment available to its customers.

Applications include bonding/fastening, EMI/RFI shielding, surface protection, insulation, thermal management, masking and vibration damping. These may be found in such markets as medical device, alternative energy, electrical, electronics and automotive.

Materials pages reveal the broad base of materials and vendors employed by Fabrico. Material categories include papers and films, foams, laminates, tapes, liners, coated fabrics and adhesives. With alliances developed over many years, Fabrico’s list of vendors is a veritable “who’s who” for flexible materials, featuring world-class suppliers such as 3M, Dupont, Permacel, Saint-Gobain and Sabic (formerly GE plastics).

Fabrico’s manufacturing capabilities include high-speed punch presses, state-of-the-art wide-web laminator, delta servo-driven rotary press, water jet cutter, aquaflex flexographic press, and slitting machines. With computer-controlled complex processes, such as in-line lamination and die cutting, Fabrico can assist OEMs with full manufacturing solutions.

“As one of the leaders in providing design and manufacturing services for flexible materials, Fabrico has built a strong foundation of knowledge,” said to Bob Thomas, president and chief executive officer of EIS, parent company of Fabrico. “The new web site will educate visitors on flexible materials and Fabrico’s capabilities.”

Norplex-Micarta’s New NP613 Provides Structural Support, Electrical Insulation in
Power Transformers

Norplex-Micarta has released NP613, a high performance thermoset composite material for superior structural strength and electrical insulation in transformer applications. NP613 is also oil-resistant and maintains its mechanical strength when used in oil-filled transformer equipment for high voltage applications.

NP613 is used to separate and isolate electrical contacts. This provides electrical insulation and protection against arcing caused by the input voltage or changes in voltage, and thus, prevents transformer failure. NP613 also provides the necessary structural support when the contacts need to be engaged. The high mechanical strength of NP613 is critical in this process, as extreme force is exerted on the separators with each gear shift. Additionally, NP613 maintains dimensional stability at elevated operating temperatures, guaranteeing that the contacts will be precisely separated and engaged as needed. 

NP613 is constructed from an electrical grade of Kraft paper and specially modified resin. NP613 typically has a flexural strength in the range of 27,000 psi and a compressive strength in the range of 40,000 psi. Its maximum operating temperature is 140°C.

BASF has developed a new engineering plastic that markedly reduces the risk that electronic components will malfunction due to contact with moisture or oil. The electrical conductive paths of these components can easily be overmolded with the plastic to form a tight seal. This new material is a transparent, non-reinforced copolyamide (PA) that goes by the name Ultramid Seal-Fit. It stands out for its good adhesion to metals on the one hand and to plastics, such as Ultramid (PA) and Ultradur (PBT) on the other hand. This product has been specially developed for the tight overmolding of metal inserts, thus accounting for an optimal bond in the component. Many approval samples have already been successfully tried out and the first serial applications are in the planning stage. The material is now already available in commercial quantities.

Injection molding instead of gluing or pre-coating
Until now, the limited adhesion of the housing plastic to the metal as well as the differing thermal expansion of these two materials have made it difficult to attain a really tight covering of metal inserts. Complicated sealing methods involving silicone adhesives, hot melts, impregnation or pre-coating of the metal were necessary. Ultramid Seal-Fit is a tailor-made technical solution now on hand that can be completely implemented via injection-molding technology.

Tight overmolding: sealing by means of injection molding in two steps
In the first step, the material insert is partially premolded with a precise fit and subsequently, in the second step, conventionally overmolded with a classic housing plastic such as Ultramid A3EG6 or Ultradur B4300 G6. Wherever metal inserts are premolded, the first process step offers an additional benefit, with Ultramid Seal-Fit the electrical conductive paths are not only affixed in place but also tightly sealed at the same time.

Metal parts thus overmolded are sufficiently sealed against water, oil and gas, as the experts of the Plastics Institute in Lüdenscheid, Germany have demonstrated in comprehensive temperature-shock tests on special test components. Among all of the other materials tested, this new BASF plastic is suitable for the requirements of the automotive industry. Application areas are sophisticated mechatronic components such as transmission and brake controls, sensors and plug-in connectors, especially in automotive construction.

Robots with Roid Rage?

North Carolina State University scientists have devised new materials that aim to put some serious muscle behind robots or biomedical devices.

The artificial muscle materials are activated by an external electrical field and then change dimensions in specific directions. Besides a pumped-up robot or smart prosthetics, other uses for these materials could be small vehicles that fly or slither into a cave, responsive textiles, steerable catheters, microfluidic or haptic devices such as continuous-action micropumps and refreshable Braille pads and other biomedical applications.

In a paper published in the most recent edition of Advanced Materials, the NC State researchers, Dr. Richard Spontak, professor of chemical and biomolecular engineering and materials science and engineering, Dr. Tushar Ghosh, professor of textile and apparel technology and management, and Ravi Shankar, a doctoral student in fiber and polymer science and materials science and engineering, show that their materials produce a great deal of stretch - or actuation strain - with a greatly reduced electrical field.

"That's important," said Spontak, "because a reduced electric field and high field-induced displacement constitute the holy grail for electrically responsive organic materials targeted for advanced engineering and biomedical applications.

"Our material is a type of electroactive polymer called a dielectric elastomer. There are many different dielectric elastomers currently available, but ours is a blend of a molecularly self-organized polymer - called a block copolymer - and a block-selective oligomer such as mineral oil," said Spontak. "It is attractive because of its low cost, light weight, robust mechanical properties and potential to emulate biological muscle." 

"The NC State material also shows a higher electromechanical coupling efficiency - the ability to turn electrical energy into mechanical work - and significantly fewer property changes due to either actuation or mechanical cycling than other tested materials," said Ghosh.

"When an external electric field is applied across the material from compliant electrodes on opposing sides of a film," Ghosh explained, "the active region of the elastomer squeezes together while enlarging laterally. The compression is due to the development of a 'Maxwell stress,' and is the underlying principle by which dielectric elastomers function."

In the paper, results demonstrate that the NC State materials attain actuation strains of about 250 percent on an area basis, and coupling efficiencies greater than 90 percent, which are the highest reported to date in this growing field of smart materials.

"The scientific literature is filled with numerous candidate materials tested for efficacy as artificial muscles. But since the NC State materials are a carefully chosen mixture of different components with specific functions, they can be physically tailored to achieve broadly different performance, giving them remarkable versatility that other, more conventional, electroresponsive materials are not able to match," Spontak adds.

And when the first robotic arm pins a human arm in an arm-wrestling match - it hasn't happened yet, but to some engineers it's akin to computer scientists developing a machine able to defeat a human in chess - the Spontak-Ghosh team wouldn't be surprised if their nanostructured dielectric elastomers provide the muscle behind the victory.

Global Powder Metallurgy Market Set to Reach Almost $30 billion by 2012

The worldwide market for powder metallurgy (PM) components is expected to approach $30 billion by 2012, growing from $23 billion in 2007 at an average annual growth rate (AAGR) near 5 percent. Over the period, the traditional PM markets of North America and Europe will lose market share to China, India and other expanding Asian countries.

Specifically, the North American PM parts business, which was worth about $5 billion in 2007, will grow to $5.5 billion in 2012. The current $9.5 billion European PM market is expected to reach $11.6 billion in 2012. In contrast, the Asian market for PM components is estimated at $7.62 billion in 2007 and is expected to increase to $12.6 billion in 2012.

This is according to a new market study entitled “The Powder Metallurgy Industry Worldwide 2007-2012” released by Materials Technology Publications. Featuring more than 450 pages and over 100 tables of statistical data, this third edition of the report also examines the raw materials (metal powders) supply sector in detail. The high quality of today's metal powders makes possible a wide range of new PM materials for specialized demands such as bearings, bushings, gears and pistons for industries ranging from automotive and aerospace to medical and electronics. The technology offers significantly improved performance and greater design flexibility compared with traditional metalworking techniques such as casting, extrusion or forging.

In most industrial countries, 70 to 85 percent of finished PM components are for the automotive industry. The North American PM industry continues to suffer because the US automotive industry has been losing market share to Japanese companies, who tend to use less PM parts per vehicle. In addition, other Asian automobile makers, particularly those in China and India, are set to be major competitive forces within the next five years. As the major powder metallurgy markets in North America, Western Europe and Japan are relatively mature; the established PM industry in these areas is looking to expand into other geographic regions, especially China, India and Eastern Europe.

Information concerning the activities of hundreds of companies (including financial results and market position) is also provided in the report, as are the R&D activities of research centers and other organizations worldwide.

“The Powder Metallurgy Industry Worldwide 2007-2012” is available as a printed paper version or as an electronic version on CD. The price of the report is $2,600.

Zero Downtime 2007
November 6 - 7, 2007
Scottsdale, Ariz.

Zero Downtime 2007, Nov. 6-7 in Scottsdale, Ariz., is a two-day conference focused on the latest advancements in protecting electronic equipment for data centers, communication and control networks, 24X7 industrial and facility systems, infrastructure and emergency service operations and other mission-critical electronic systems.
Topics discussed will include new developments in power protection and reliability including UPS, surge and circuit protection; thermal protection including controls, sensors, heating, cooling and environmental mitigation; condition monitoring and control including predictive and reliability capabilities, preventative maintenance; EMI shielding; and electronics packaging solutions such as enclosures shelters, cabinets and cases.
This November event will be organized to provide numerous opportunities for networking, discussion sessions, daily luncheons, a cocktail reception, and a large, co-located exhibit (co-located with Remote Monitoring and Networking 2007 and Onsite Power 2007) with dedicated hours and exhibit only passes for industry attendees.
Register today at www.EquipmentProtectionMagazine.com/zero07_reg.htm or call 800-803-9488.