Like a bug that crashes into and sticks on your windshield, particles of metal stick to surfaces on aircraft engine components when propelled at speeds of 500 to 1,500 meters per second. Re-searchers at Sandia National Labs are studying what happens when metals, alloys, and ceramic blends measuring 10 to 15 microns smack into engine components in a process called cold spray. Unlike thermal sprays that re-quire preheating the particles into a semi-molten state, the new cold spray process works at room temperature. Cold-sprayed materials typically re-main at room temperature until slamming into a substrate, which the researchers believe helps the metal particles form tight bonds. The disadvantage with semi-molten materials is that when they cool, they create residual stresses that cause defects later. The researchers think the cool process is better because the high-velocity impacts disrupt the metal oxide films on the particles and substrate surfaces, pressing their atomic structures into one another. "Cold-sprayed coatings have a higher density and smoother finishes than traditional thermally sprayed coating's," says Sandia researcher Mark Smith. "The electric properties tend to be better too." Smith notes that the Sandia team is still characterizing the coatings other properties. Sandia is currently working with a consortium of eight U.S. companies in an effort to improve the technique. Additional applications for the process include depositing coatings and conductive metals onto automotive components, building components layer by layer, and joining chemically dissimilar materials together as an alternative to welding. For more information, go to www.sandia.gov.
What makes this movie stand out from the typical high school sports story is that the teenagers are undocumented immigrants, and the big game is a NASA-sponsored marine robotics competition. Like many other Hollywood movies, however, Spare Parts only tells part of the story. What the film shows -- and doesn’t show -- raises important issues affecting STEM education in the US.
Instead of sifting through huge amounts of technical data looking for answers to assembly problems, engineers can now benefit from 3M's new initiative -- 3M Assembly Solutions. The company has organized its wealth of adhesive and tape solutions into six typical application areas, making it easier to find the best products to solve their real-world assembly and bonding problems.
Load dump occurs when a discharged battery is disconnected while the alternator is generating current and other loads remain on the alternator circuit. If left alone, the electrical spikes and transients will be transmitted along the power line, leading to malfunctions in individual electronics/sensors or permanent damage to the vehicle’s electronic system. Bottom line: An uncontrolled load dump threatens the overall safety and reliability of the vehicle.
Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.