Patented method improves powder-metal coatings
Engineers at Kemp Development Corp., Houston, TX, are developing a technique that may improve plasma spraying, composite manufacture, and powder metallurgy operations. Applications include thermal treatment, diffusion hardening, and the creation of spherical ceramics. Kemp recently patented the method, which eliminates inadequate mixing and thermal gradient problems by mechanically fluidizing metal powder in a sealed system under precise temperature and pressure conditions. Kemp engineers say the system combines the atmosphere control of a vacuum furnace with the heating speed and uniformity of a fluidized bed. The U.S. Department of Energy and Los Alamos National Lab recently awarded Kemp $122,000 in grants to pursue development. For details, FAX Kemp at (713) 482-7026.
Helium cools this portable system
A new cooling system designed by engineers from Lawrence Livermore National Laboratory promises to cut costs, preserve the environment and open up a new field of portable cooling systems. Small amounts of helium act as a coolant, rather than the CFCs used in most refrigeration systems. The compact system uses low power and exhibits very low vibration, say engineers. To reduce vibration produced by the motorized compressor, the system uses microprocessors to measure vibration and produce a counterforce that cancels most of the movement. The method makes the compressor motor more efficient and extends its working life, claim engineers. They are filing a patent application, and the Laboratory is seeking to license the design to industrial partners. The design may find application in food refrigeration and scientific instrumentation. "I see this system as setting the standard for the future," says Ken Neufeld, the cooling system's principal designer. For details, FAX Gordon Yano at (510) 424-2780.
High-speed pulse welding eliminates distortion
A high-speed welding technique developed for bonding powder metal components achieves a diffusion bond without distorting or discoloring the components. So claim engineers at Process Equipment Co., Tipp City, OH. Engineers at PEC's Joining Technology Group use a very high current pulse at low voltage and very short exposure to bond ferrous, nonferrous, high-carbon, or dissimilar materials. The technique is useful for creating bonds near sensitive gear profiles and for welding heavy races or hubs to lighter complex stampings without changing the stamping shape, say engineers. The welds are repeatable and meet close tolerances, and can take as few as ten milliseconds. The technique offers low operating costs, requires little energy, and needs no cover gas or flux, say engineers. For more information, FAX (513) 667-9322.
Bomb detector concept yields a portable 'sniffer'
Bomb detection is one way to thwart terrorists. At Los Alamos National Laboratory, engineers have devised a new method for detecting explosives that sweeps up trace, microscopic particles of an explosive and uses a photomultiplier tube to register the mini-flare created when the particles burn in a heated chamber. The method, for which the Laboratory has filed a patent application, could be easily incorporated into portable devices to screen luggage, vehicles, or people for explosives residue, say engineers. Los Alamos physicists Herb Funsten and Dave McComas recognized that because the chemical structure of explosives allows them to burn rapidly, light flashes from tiny, burning specks of explosives should produce a unique optical signature. "This method could provide a simple solution to a complex problem that has been scrutinized for more than 30 years with limited success," says Funsten. For more information, FAX Dave McComas at (505) 665-7395.
Carbon films give tools diamond-like hardness
Diamond-like carbon films under development at VTT Technical Research Centre of Finland give machine parts made of conventional materials a hard, thin coating. The films, which are only a few atoms thick, reduce friction of parts in extreme applications, where lubricants may not be practical. To deposit the films, VTT engineers use vacuum arc discharge and pure carbon plasmas that they say deliver properties similar to those of natural diamond. One of the most important features of the technique is its low deposition temperature of less than 100C. This permits deposition on polymer parts, say engineers. They claim that the films significantly improve the performance of cutting tools for wood and non-ferrous metals as well as metal-forming and plastic molds. For details, FAX the Manufacturing Technology group at +358 0 456 7011.
Medical instrument may ease artery surgery
A tiny medical device under development at Sherine Med AG, Uettligen, Switzerland, may allow doctors to clean clogged arteries and veins with reduced risk of damage caused by plaque clots. The "Redha-Cut" atherectomy device uses two cutting blades to remove plaque from the walls of arteries and veins, then captures the plaque to prevent it from being swept away by the blood. Using a wire to guide the device, doctors would remotely open its blades to a desired diameter, collect the cut plaque, then close the blades like an umbrella and withdraw the tool. The procedure can be repeated several times, with the device being rotated 60 to 90 degrees along its longitudinal axis each time. The device measures 2.65 mm in diameter when closed and 4.9 mm when open. It shows potential to greatly reduce operating time and costs, say Sherine engineers. For more information, call +41 31 829 19 17.
Will 'robo-ants' of the future act as a bomb squad?
An "ant colony" of tiny robots may someday perform tasks too difficult or dangerous for humans, such as inspect nuclear power plants, carry surveillance cameras into small spaces, or seek and remove unexploded bombs. Eight such robots developed by an engineering student at the Massachusetts Institute of Technology, Cambridge, MA, are already capable of searching for small targets and communicating simple information among themselves. The robots, which measure about 1.5 inches, use treads powered by beeper motors to move and have infrared transmitters and receivers to communicate. Their tiny "mandibles" can pick up small objects. The work comes from MIT's Artificial Intelligence Laboratory and was funded by the Advanced Research Projects Agency. For details, look at WWW site http:www.ai.mit.edu/projects/microrobotics/microrobots.
A non-invasive way to detect current or potential heart defects
A computerized system that uses magnetic resonance imaging to measure cardiac motion is giving researchers a non-invasive way to detect current or potential heart defects. Unlike previous efforts, the three-dimensional "movies" of the heart being developed at Johns Hopkins University, Baltimore, MD, require only a 30-second or one-minute scan. "Early scans took 20 minutes, and the image processing was difficult," explains Dr. Jerry Prince, an electrical and computer engineering professor and project leader. The new technique will allow doctors to watch a beating heart as it moves through a complete cycle and identify damaged areas long before they can be diagnosed by other techniques, says Prince. He is also pursuing applications in brain mapping, nondestructive evaluation of materials, synthetic aperture radar, and geophysical imaging. For more information, FAX Prince at (410) 516-5566.
New method whips up the lightest solids on earth
Aerogels, which can be as much as 99.9% air, are a far better insulator than fiberglass and can support more than a thousand times their own weight. But until recently, production required hazardous solvents and high temperatures and pressures. Now, engineers at Sandia National Laboratories, Albuquerque, NM, have found a less-costly way to produce aerogels at room temperature and pressure. Their technique chemically modifies the interior surfaces of the molecular mesh of the gels, allowing them to collapse during the evaporation phase at room temperature, then spring back. The technique works for both bulk and thin-film processing, say engineers. The aerogels' final composition is as much as 98.5% air. Aerogels may find use as lightweight components in spacecraft, in sensors to detect chemical warfare agents, or as super-insulation for appliances and between window panes. For details, FAX Julie Clausen at (505) 844-6367.
Optical processor targets tanks-and now, tumors
A technology applied to detecting camouflaged tanks and faults in the welds of Titan missiles has found a new application: early detection of breast cancer. Engineers at Lockheed Martin Astronautics (LMA), Denver, and Rose Health Care, Denver, are applying high-speed processing of medical images to early detection. Breast cancer is the leading cause of death among women 35-54. The design team used an optical processor to pack key circuits into a more dense arrangement than possible on an electronic processor. Since photons are fast and less prone to heating up than electrons, optical processors operate at much higher speeds-and more efficiently. Though still in the early stages of design, engineers hope that photon-based computing will support the complex calculations needed to detect cancerous lesions from acquired imagery. The two companies will apply the optical processor technology to automated medical image analysis. For details, FAX Mike Henry at LMA, (303) 971-1627, or Kenneth Weil at Rose, (303) 333-7511.
Ultra-sensitive detector will target IC contaminants
As integrated circuits move to the next level of miniaturization, metallic contaminants are expected to become a serious problem. Even widely spaced atoms of certain metals lying on the wafer's surface can gather to form defects. To measure such extremely low levels of metallic impurities on the surfaces of silicon wavers, engineers at Stanford University's Linear Accelerator Center and Hewlett-Packard Co., Palo Alto, CA, have teamed to create an X-ray detection system. The proposed detector would use high-power synchrotron X-ray sources to allow an immediate ten-fold improvement in detection sensitivity, say engineers. The group will devote one year and $150,000 to develop parameters for such a device. FAX (415) 926-4999.