Technology Bulletin

Capacitive touchscreen touted as world's largest

MicroTouch Systems, Inc., Methuen, MA, claims it has built the world's largest capacitive touchscreen, a 29-inch diagonal touch sensor designed for navigation radar systems. The sensor, developed for use as the primary interface to an advanced rasterscan collision avoidance radar (RASCAR®) by Sperry Marine, Inc., Charlottesville, VA, will enable radar operators to touch and interact directly with images on the screen, while controlling the system's operation through the use of on-screen soft-keys. "The scaling up of our analog capacitive touch technology for monitors represents a unique technical achievement that no other touch technology can easily accomplish," boasts Steve Kreindler, MicroTouch product manager. FAX: Annette Burak at (508) 659-9100.

Stainless steels set new standards for machinability

"The most significant improvement in the machinability of stainless steel in the last 30 years." So proclaims a statement from Carpenter Technology Corp., Reading, PA, about its new Project 7000™ stainless steels series. The steels can be machined at speeds up to 50% faster than possible with the company's own line of Project 70™stainless steels. The new steels should enable many metalworkers "to increase productivity dramatically, reduce labor and part costs, shrink cycle time, expand production capability with existing equipment, and more easily machine difficult parts," observes Carpenter. The greatest benefit is seen for those metalworking operations that use large volumes of small-diameter bar stock on long production runs. FAX: (610) 208-2858.

'World's highest power superconducting motor' demonstrated

Scientists and engineers at the Naval Research Laboratory (NRL) and the Naval Surface Warfare Center, along with industrial partners American Superconductor Corp. (ASC) and Intermagnetics General Corp. (IGC), have set what they claim to be a new world record in superconducting motor performance using high-temperature (Tc) superconductors. The field magnet for the motor consisted of two sets of high Tc superconducting coils made from bismuth strontium calcium copper oxide. One set was made by ASC, the other by IGC. Both sets were installed in the motor to achieve the high power level. Donald Gubser and Louis Toth, of NRL's Materials Science and Technology Div., say the motor demonstration may have direct impact on ongoing Navy programs in minesweeping, electric drive, and superconductive magnet energy storage. They also cite other potential applications, including: transportation, electric power transmission and distribution, and magnetic resonance imaging. FAX: (202) 767-6991.

Nanoparticles add strength to ceramics

During the late 1980s, Japanese scientists discovered that the mechanical properties of ceramics could be improved by adding ultrafine (100-200 nm) silicon carbide (SiC) particles. Subsequent work at Lehigh University, sponsored by EPRI and the U.S. Office of Naval Research, has confirmed this discovery--and shed new light on the probable mechanism involved. In general, ceramics tend to be brittle: when bent, they break easily, without deformation, along surface defects. Lehigh researchers have found that the presence of SiC nanoparticles apparently facilitates crack healing in the ceramic surface during annealing, thus making the surface stronger. In contrast, annealing a single-phase ceramic material actually makes surface cracks grow. According to the latest results, ceramic-SiCnanocomposites show a significant increase in high-temperature rupture strength, compared with single-phase ceramics. In addition, the creep rate of the nanocomposites is more than a hundredfold lower. The results also show large increases in abrasion resistance. FAX: EPRI's Wate Bakker at (415) 855-2287.

'Smart material' helps fight noise with noise

New "smart materials" that can change shape in response to an electric charge are making it possible to fight noise with noise. So says Kevin Craig, who directs the Rensselaer Polytechnic Institute's program in the mechanics and control of active materials and smart structures. He and his students use piezoelectric materials to create tiny speakers that can react to an annoying noise by creating an equal but opposite sound wave. For instance, Craig describes a piece of office equipment that creates an irritating hum. A microscope and sensor are installed to pick up and measure the sound. To cancel such noise, Craig has built compact speakers by bonding a piezoelectric ceramic to metal plates. As controlled amounts of voltage are applied, the ceramic changes shape, causing the metal to vibrate and create noise. A computer controller triggers the plate to set off a sound wave the exact opposite of that formed by the equipment, and the two waves cancel each other out. FAX: (518) 276-2623.

Absorber rod technology targets spent-fuel storage

Advanced Refractory Technologies (ART), Buffalo, NY, has joined with B&W Fuel Co., Lynchburg, VA, to develop a cost-effective absorber rod (AR) for criticality control in Pressurized Water Reactor (PWR) spent-fuel assemblies. The rod, inserted into the guide tubes of spent-fuel assemblies, reduces reactivity. By using the ARs, ART reports that some utilities can increase the capacity of their spent-fuel storage racks, or eliminate the need for re-racking spent fuel. Other utilities, says ART, can increase the lifespan of deteriorating spent-fuel racks, or use the rods to help control criticality in dry storage applications. The rods consist of alumina-boron carbide pellets enclosed in stainless steel cladding to ensure long-term stability in the spent-fuel pool environment. FAX: David Matthew at (716) 875-0106.

Ceramic filter technology breathes life into turbines

Just as people need air to breathe, high-temperature gas turbines need clean fuel to burn to prevent damage to sensitive internal parts. The most effective style of filter for this purpose, called a candle filter, resembles a 5-foot-high, 2 ½-inch-diameter laboratory test tube. The gas is forced through the porous material, leaving impurities clustered as a filter "cake" on the outside of the filter. Conventional candle filters consist of silicon carbide grains held together by a clay or glassy binder, which is comparatively heavy and brittle. Gas being filtered is at a very high temperature, and the blasts of air used to blow the filter clean are usually at room temperature. Because of the extreme temperature and pressure changes, such filters tend to weaken and break, sending a stream of impurities into the turbine. To solve this problem, the Oak Ridge National Laboratory and the 3M Co. have developed the 3M Ceramic Composite Filter. It consists of a combination of continuous and chopped ceramic fibers reinforced with a silicon carbide matrix. The continuous fibers strengthen the filter and remain intact if the filter breaks. Also, the filter's thin wall makes it less susceptible to breakage from extreme changes in temperature and pressure. Other uses include: filters for waste incinerators, metal smelters, and advanced diesel engines. FAX: (615) 574-0595.

Model determines iron and zinc in galvanneal coatings

The American Iron and Steel Institute has announced that an online tool is now available to help determine the iron and zinc phases present in galvanneal coatings. A joint research effort of Data Measurement Corp. (DMC), Jet Propulsion Laboratory, 15 North American steelmakers, and the DOE, results of the two-year project should enable galvanneal producers to more accurately measure zinc-iron coatings. This, in turn, can help them optimize critical product properties demanded by automakers, the principal users of galvanneal. "We believe this technology will also aid in the basic understanding of the galvanneal process, and the relationship of phases to such properties as appearance and powdering," states Dominique Gignoux, president of DMC. FAX: Joseph Vehec at (412) 566-2330.

Reinforcing rod solves steel rebar corrosion problems

Marshall Industries, Lima, OH, has found a solution to common corrosion problems in steel reinforcing bars or rebars. Used to reinforce concrete in infrastructure, construction, and coastal applications, steel rebar corrosion can lead to cracking of the concrete, ultimately weakening the structure. Marshall's answer: the fiber-reinforced-plastic (FRP) C-BAR™. Made with Owens-Corning Advantex™ composite reinforcements, the C-BAR reinforcing rod is a hybrid of Type 30 glass and continuous rovings. It will not corrode in alkali or winter salt conditions, is lightweight and non-conductive. Owens-Corning also points out that the material can economically compete against corrosion-protected steel, such as epoxy-coated steel and galvanized rebars. FAX: Salem Faza at (904) 992-9371.

System measures smooth or rough skin without contact

A non-contact, laser-based system allows "even the smallest change in skin characteristics to be objectively measured and verified," according to UBM Corp., Roselle, NJ, its developer. The Dermaprofile system consists of the non-contact laser sensor, movable stages (x, y), and a computer-based controller that includes operating software. The Windows-based software contains a Macro program that automatically repeats any measuring process with a single keystroke. Results can be stored in the computer for further evaluation, or a hard copy with color graphics can be printed of the findings. The system lets users measure aging effects, progress of plastic surgery, wrinkle depth treatment, callous formation, and infectious skin diseases. FAX (908) 241-7288.

Integration of vehicle structure research underway

A.O. Smith Corp., Milwaukee, will undertake a project aimed at integrating research in steel and aluminum vehicle structures. Other participants in the joint study, funded in part by the Department of Commerce, include Caterpillar Inc., Lincoln Electric, and U.S. Steel. "This project will concentrate on developments in steel and aluminum rolling, cutting, forming, welding, and process simulation," says Sam Licavoli, president of A.O. Smith Automotive Products Co. "Our goal is to achieve significant improvements in fatigue life and allowable fatigue stress for steel and aluminum fabricated structures used in heavy equipment and surface transportation." During the first year of the study, A.O. Smith will focus on alloy evaluations, cutting process development, high-volume hole making.