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The Fleck Materials Seminar, held in conjunction with FCC '99, was held on the afternoon of September 30 with the following speakers participating:

1999 FMS Speakers

This year’s distinguished group of industry executives was composed of the following speakers, listed in order of presentation:

Copper-based Alloys Examined

Fleck Research opened the seminar with a report on copper-based alloys for contacts, noting that nearly 400 billion contacts were produced within U.S. non-captive factories in North America last year. Of these, almost 170 billion were utilized in printed circuit connectors, while another 124 million went to automotive connectors.

Electronic connectors made up the bulk of copper-based alloy use during 1998 with 220 million pounds, Fleck reported, while the industry in general used 316 million pounds from non-captive manufacturers. Captive manufacturers contributed another 103 million pounds of copper-based alloys.

Polymer resins for insulators accounted for 10 billion insulators in North America last year, with non-captive manufacturers accounting for nearly eight billion of these. Fleck reported that North America utilized 175.7 million pounds of polymer in 1998.

Worldwide, the connector industry utilized 412.5 million pounds of polymer, with PBT accounting for nearly half of the total at 193.6 million pounds and nylon 66 taking 26.3% with 108.3 million pounds.

Thin Gold Technology for Electronics

Apex’s I-Yuan Wei, recently retired from AMP after 17 years as director of contact materials, has contributed significantly to thin gold technology, palladium and palladium alloy plating, non-corrosive coating, hydrogen embrittlement, pulse plating alternative to tin-lead, graphite composite coating and high-temperature coating.

Speaking on thin gold technology for electronic contact applications, Wei noted that this contact interface is fundamental to connectors. Separable interfaces involve geometry, normal force and finish/morphology, while permanent interfaces are concerned with mechanical (crimp, press in, insulation displacement) and metallurgical (soldering and welding).

Reasons for using gold contacts, he explained, include metal-to-metal contact, which offers corrosion protection, free oxide film and no fretting. Electrical and thermal properties also are factors.

Thin gold technology possesses cost vs. performance advantages of porosity, wearability and thermal stability, Wei pointed out. “There is,” he added, “no good replacement for gold.” Potential contact finishes include composite gold, composition modulated alloy, laser-enhanced plating, solder jet deposition, vacuum deposition, pyrolysis, inlay and conductive polymer.

Copper Alloys in Electronics and Automotive Markets

Abid Khan has spent the past quarter-century at Olin Brass, starting as a research engineer before switching to technical marketing. As director of market development, he is responsible for the company’s high-performance alloy business worldwide, focusing primarily on the electronic and automotive end-use markets.

“The name of the game in the electronic connector market is smaller, faster, cheaper and reliable,” Khan stated. “The challenge for the designers is how to continue to miniaturize, maintain a rugged construction using less material, maintain signal integrity at ever-increasing speeds and accommodate automated assembly.”

As the density increases, he noted, the designers are going from conventional pin and socket design to area array interconnects—similar to what is used in semiconductor packaging—or blade and beam-type contacts. Khan pointed out that the global workhorse in the electronic connector segment are the phosphor bronze alloys. Brass is used where it provides acceptable performance and beryllium copper is used only if one needs the unique properties it offers because of the significant cost penalty, he added.

“More recently, our customers have demanded a cost-effective alternative to phosphor bronzes,” Khan said. “Olin successfully introduced C663 as a phosphor bronze replacement alloy in 1997. It offers higher conductivity, similar strength/bend and stress relaxation performance.”

Khan noted that his company is a major supplier to the U.S. automotive market, which includes Japanese transplants. Olin’s position as a major supplier in the automotive segment is leveraged by choice of alloys, tin coatings and service capability, he said.

Concluding, Khan stated that in both the electronic and automotive connector segments, material suppliers will continue to be challenged by miniaturization, speed and power requirements, reliability and, in automotive applications, the environment. In addition, global availability issues and cost pressures will continue unabated.

Current & Future Polymer Trends

Ajit Munshi, a senior consultant with Apex with 30 years of experience in plastics and rubber in electronic connector manufacturing, has provided technical and consulting support in plastic materials selection, failure analysis and fabrication techniques resulting in significant cost savings for manufacturing of plastic housings.

He identified the high-performance polymer of the future as “syndiotactic styrene polymer,” produced by Dow Questra-Crystaline Polymers. This product supports high-temperature connector applications and high performance resin for electrical engineering products.

Among the competitive advantages of the Questra series are high heat resistance, simple processing and lower comparative cost, Munshi noted. He also cited stability, low dielectric constant, high insulation resistance and good tracking resistance.

Typical applications for this product, he reported, are telecommunication connectors, automotive “under the hood” electrical connectors, PCB connectors, I/O connectors and integrated circuit connectors.

“The industry is demanding higher performance with lower cost,” Munshi stated. “Polymer suppliers are developing new materials, and designers must understand performance requirements for optimum cost/performance.”

Polyphenylene Sulfide Alloys for Connector Designs

Spencer Siegel of Phillips Chemical, who has marketed high-temperature materials for the connector/socket market for the past 10 years, was instrumental in obtaining material specification for Ryton PPS in Slot 1, Seagate’s 2mm bottom entry connector, various high speed and high density connectors and sockets. He introduced a new line of polyphenylene sulfide alloys under the trade name Xtel.

Trends in the connector industry, Siegel noted, are toward surface mount technology, miniaturization and higher pin densities. Plastic material, he said, results in improved electrical, mechanical and thermal performance, as well as improved mold-filling capability and flash resistance, along with cost reduction.

“Utilization of Ryton,” he stressed, “results in thermal and dimensional stability, mechanical integrity and improved electrical performance. Xtel PPS alloys expand the capabilities of PPS to meet the demands of the connector/socket marketplace.”

Siegel pointed out the advantages of Xtel alloys, which included SMT compatibility, flash-free parts, high weldline strength, low mold temperatures and fact cycle times.

Future Trends for Metals in Connectors

Robert Michelson, a 33-year veteran of the plating and metals field, spent 24 years at AMP in the technology division, where he worked on metallizing plastic films and the problems associated with gold reduction. He was credited with company savings of over $30 million a year for his gold reduction efforts.

Regarding metal selection in the connector industry, Michelson noted that “I expect change to be very slow and gradual.” He predicted that the backbone of the metals business will remain phosphor bronze, brass and a little beryllium copper.

“Costs of metals were driven down in the 1990s, but product performance remained up,” he declared. “In the 2000s, cost will be driven way down, but there will be relaxed performance.”

Historically, he noted, products in the telecommunications and mainframe computer industry sustained a 40-year life. At present, with constant technological advances, there is a 40-month life—if that long—for desktop computers, cellular phones and consumer electronics.

Choosing the proper metal involves a consideration of the total connector system, Michelson said, adding that “Properly designed plastic parts can help avoid overstressing the metal and plating can stiffen the spring characteristics.” He noted that RS-232 connectors now are using brass where phosphor bronze was the alloy of choice.

Michelson reported that Alloy 7025 has eroded the high-end beryllium copper market with its properties close to that metal, but at a much lower cost. Alloy 171 is a beryllium copper alloy being developed to counteract that trend, and it reportedly will be available at a lower cost than historical BeCu alloys.

He cited Alloy 688 as an attempt to come up with a new alloy with superior physical properties. “However, the tradeoff syndrome hit. The alloy has poorer stress relaxation properties, higher than normal die wear and the aluminum and cobalt oxides make plating more difficult.”

One way around the problem, Michelson said, is the use of mixed metals, allowing greater versatility. What is required is a material without magnetic properties.

“We will see attempts to dethrone brass and phosphor bronze allows, but for many applications they are still the best,” he declared. “Why go to a single source for an exotic alloy at a premium price if it really doesn’t buy you much?”

Trends in Contact Lubricants

The final speaker was Bipin Doshi, who in his 30 years of industrial experience has developed lubricant formulations for automotive, metal working, aerospace and marine guidance systems. During his 20 years with AMP, he resolved corporate challenges of electrical contact and stamping lubrication, surface treatment, sealant and corrosion inhibiting coatings.

Doshi pointed out the reasons for applying a lubricant to electrical contacts—reduction of mating forces, enhancement of plating durability and corrosion protection, improving crimping and assembly tool life and solderability shelf life. The same factors, basically apply to the lubrication of contact materials.

“Value added” contact lubricants were recommended for the automotive, telecom, computer, consumer products, outdoor products, consumer electronics and power utilities industries. Doshi’s checklist for contact lubricant selection included connector materials, electrical loading, mechanical stress and operating environment.

Contact lubricants, he concluded, should offer good lubrication, low volatility, good corrosion protection, oxidative stability and compatibility with housing materials.