Burnishing leaves compressive stress in the surface of a metal part, explained Terry Jacobs, the new company's engineering vice president. In this state of perpetual compression, the surface can better withstand the alternating tensile and compressive stresses of a typical fatigue cycle.

Low-plasticity burnishing treats just the surface in need, right on the CNC machine.

One way of enhancing a surface, shot peening, blasts tiny pellets at an area to be worked. Another method, called laser shock peening, improves on the shot treatment by extending the depth to which compressive stresses penetrate, Jacobs said. In that process, a laser heats the taped or painted surface of the part. The shock wave that results as the covering expands deforms the surface, compressing it.

An advantage of both the laser method and the new low-plasticity burnishing is less cold working of the material. In the hot combustion chamber of an aircraft turbine, the beneficial compression from cold working quickly relaxes.

According to Jacobs, low-plasticity burnishing reaches to a depth four times that of conventional shot peening. It reduces cold working to a degree at least equal to that of laser shock peening. It matches the effectiveness of laser shock peening for about one-tenth the cost, he said. It adapts easily to manufacturing.

The new process supports a ball in a fluid bearing. Held in the chuck of a multi-axis CNC machine, the burnishing ball rolls over areas of the part needing treatment. The ball exerts just enough pressure on the surface to compress it while cold working it only mildly, Jacobs said.

Embed plates consist of steel studded with long rivets. When concrete is poured over the plates, the rivets extend into the concrete pad, anchoring it in place. Holes can then be drilled into the concrete to bolt vessels, equipment, and structures into place.

PT&P bend tested the rivets in its embed plates prior to shipping them to Peru, where they were used to stabilize gold mining equipment.

The company was approached by Bechtel, headquartered in Boulder, Colo., in December to provide 150 embed plates, each measuring 93 x 27 x 1 inch, to serve four gold mine tunnels operated by Minera Yanacocha, a division of Newmont Mining, operating in Cajamarca, a province in northwestern Peru. The embed plates would be used to anchor various ore feeders and other large-scale mining equipment at the mouths of the four tunnels.

According to David Baker, a chemical engineer and lead engineer for insulated support at PT&P, the Peruvian project was two-thirds larger than any previous embed plate job undertaken by the manufacturer. "We used AutoCAD to calculate how much material we would need to build on that scale, and used 40 tons of carbon steel to build the embed plates in sections," said Baker. PT&P subjected the rivets to test bending before shipping them to Peru along with drawings of their assembly.

Bechtel personnel assembled the plates into quarters in Lima, before trucking them to the mines, 4,700 meters in altitude, for final assembly at the mine site. PT&P beat its forecast of completion in March. The embed plates were delivered and installed in February.

Dimensional accuracy of the components is critical, given the expensive payload of up to $6 million. The system consists of a cassette, which holds 25 wafers, inside an enclosure that protects it from the external environment.

During integrated circuit fabrication, a robotic arm extends into the FOUP to lift out each of the wafers for processing. The wafers lie in the cassette separated by 10 mm. The process allows for a maximum tolerance of 0.5 mm. Depending on the processing, the wafers can be hot when they are returned to the FOUP after processing, but the container must hold its shape.

Front opening unified pod, manufactured by Entegris, transports silicon wafers through various processing steps to produce integrated circuits.

Entegris specified polyetherether-ketone polymer, supplied by Victrex USA Inc. of Greenville, S.C., for the cassette, as well as for areas of the FOUP housing that must interface with different types of equipment during fabrication.

"Grooves on the bottom of the FOUP are made with PEEK polymer," said Wayne Olson, technical director of wafer handing systems for Entegris. "During processing, the FOUP must sit on top of a process tool load port, and the grooves are used to accurately position it on top of the half-inch-diameter pins sticking up from the load port."

PEEK was chosen for the spot where the FOUP sits on the pins—a point of friction that could result in the release of particles that might corrupt the process.

Another interface point where PEEK was specified for its dimensional stability is a rectangular appendage that sits on top of the FOUP—a sort of square handle that is attached to the housing. "When the robot's finger-like grippers pick up the FOUP to move it to another location, the spatial location of the top handle must be in the same place each time with respect to the FOUP housing," he said.

The company will launch an Accord sedan in Europe in 2003 with its own two-liter diesel engine and, in the meantime, will offer a diesel version of its Civic compact in Europe in November using 1.7-liter engines from GM affiliate Isuzu Motors Ltd.

Diesel engines, with their greater fuel efficiency and lower greenhouse gas emissions, have grown increasingly popular among cost- and environment-conscious drivers in Europe, a region that has long been Honda's Achilles' heel.

A decision on where to make the engines is expected by the end of next year.

Most engineering plastics are polymer blends. Such blended technologies are already in wide use for large parts such as car bumpers, but new applications are emerging for parts similar in size to the dispersed polymer droplets.

Using visualization technology to study the polymer blending process, scientists at the National Institute for Standards and Technology in Gaithersburg, Md., have discovered the formation of novel polymer structures that can occur in microscale applications. NIST measurements show that, when two incompatible polymer liquids are mechanically blended together, one may deform into very long strings that are extremely stable. This transformation occurs under special conditions—when the size of a typical polymer droplet is comparable to the size of a part being made, as in ultrathin films.

When the processing meets these conditions, the droplets reorganize on their own into what scientists call superstrings.

Potential microscale applications of superstring components could include conductive plastic wires, ultrathin composite materials, and tissue engineering, according to NIST scientists.

"In congested areas, more than 50 percent of the cost of repairing a bridge goes to traffic control," Harik explained. On highly salted roads, reinforcement rods that last 30 to 40 years instead of the usual 10 to 20 help to justify the greater initial expense of advanced materials, he said. For a bridge deck whose steel reinforcement costs $5,000, the same material in carbon fiber runs between $20,000 and $50,000, depending on design and the variety of carbon fiber that makes up the rod.

Corrosion of the reinforcing rods is particularly bad in areas of extensive salting. Concrete absorbs the salty runoff. Eventually, the steel rusts and its bond with the concrete weakens. Then, the concrete cracks and crumbles.

The pour of the Two Mile Creek bridge deck on Kentucky Route 5210: Darker elements resting on green "chairs" are carbon-fiber rods.

The Two Mile Creek bridge used 3/8-inch-diameter rod instead of the 1/2-, 5/8-, or 3/4-inch diameters common for steel reinforcing because that's what was available, Harik said. The design actually used more carbon-fiber rods than it would have steel rods because codes demand a minimum amount of reinforcement.

Another application for carbon-fiber reinforced concrete is in structures that need to be completely free of magnetic interference, Harik said. The magnetic resonance imaging room of a hospital is one good example, he said.

Among the major elements of the $227 million port project is the construction of a 1,150-foot-long by 90-foot-wide semi-floating quay wall that will reclaim about 86,000 square feet of land for Monaco, where acreage is at a premium.

The quay wall will be equipped with a lighthouse, will incorporate rail and road links, and will contain a 400-space parking lot. The wall will move slightly on three degrees of freedom on a caisson. Connecting the quay wall to the caisson is the gigantic ball-and-socket joint, cast by NFM Technologies at its Creusot-Loire factories. The 600-metric-ton joint consists of a support plate, flange, mating flange, and an inner ring.

The dry dock in Algeciras, Spain, is the only one in the Mediterranean big enough to handle construction of the quay for La Condamine.

Engineers will connect the joint to the wall by means of a socket held by 60 prestressed bars fitted into a metal structure that is built into the caisson. Along with a ballasting/deballasting system and mooring chains, the joint will enable the quay wall to withstand the onslaught of ferocious "hundred year waves." The design allows a wave to displace the quay wall's ends by 43 feet, according to hydrodynamic simulation and modeling.

The quay wall is being constructed in the Spanish port of Algeciras, virtually the only Mediterranean dry dock capable of accommodating the colossal sections of steel and concrete. The wall, joint, and other major components will be assembled on site at La Condamine. The new port is expected to become operational sometime next year.

Sheldahl Inc. of Northfield, Minn., a producer of substrates, printed circuitry, and flexible laminates for the automotive, electronics, and data communications markets, is planning to sell a portion of its technical materials business.

A supplier of monitoring and protection systems to utilities, Schweitzer Engineering Laboratories of Pullman, Wash., has formed a unit called SEL Industrial Solutions Group, which is adapting the company's products and services for industrial customers. The company's various products are intended to monitor power systems and control them to avoid damage to equipment and plant processes.

Dresser Rand, based in Painted Post, N.Y., will supply separable compression systems for the Gujarat State Energy Co.'s gas booster application in the Hazira gas fields near Surat, India. The two systems use 5D VIP4 fuel gas booster compressors to serve gas turbine generator sets driven by Waukesha gas engines, and are scheduled to begin operating in the early fall.

The European subsidiary of Montgomery Watson Inc., a Pasadena, Calif., engineering firm, will supervise construction of a sewage treatment plant and 300 additional kilometers of sewer pipelines on the Indian Ocean island nation of Mauritius. When the three-year project is completed, sewer service will be available to about 320,000 inhabitants, more than triple the current number, and produce a treated effluent that will be used for agricultural irrigation.

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