National Ignition Facility

Scientists at the National Ignition Facility, part of the Lawrence Livermore National Laboratory, recently set a record by combining 192 synchronized lasers into a single UV laser beam with 1.875 million joules of energy. The laser burst lasted 21 billionths of a second and generated 411 trillion W of peak power, 1,000 times the amount being used in the entire U.‹S. at a given instant. This means the NIF laser contains 100 times more energy than any other laser. Researchers hope the laser will eventually be able to start a fusion reaction, which could lead to an entirely new type of power generation

Self-adaptive water jets cut almost anything

University of Nottingham

Researchers at the University of Nottingham are developing “self-learning” controlled-depth, water-jet-milling that works on multigradient surfaces with high levels of accuracy and without human intervention. Project leader and professor of manufacturing engineering Dragos Axinte says, “The accuracy of the ConforM2-Jet self-learning control is due to mathematical models we use for materialremoval and process-monitoring techniques that make corrections as milling happens. The machine can also mill complex shapes out of difficult-to-cut materials.”

Water-jet machining is a promising method for shaping difficult-to-cut materials such as advanced aerospace components, orthopedic implants, ultraprecise lenses, composites, and superabrasives including diamonds. It uses a jet of water as small as 1 mm or less in diameter that is released under pressure at speeds as much as three times the speed of sound. With the addition of abrasive particles, the high-velocity jet cuts even the hardest material into the most-complex shapes. Or it can use low-pressure jets to polish optical molds and lenses.

Based on the key elements of milling, the technology uses specially developed CAM algorithms to generate the jet plume’s theoretical path. The self-adaptive module also receives real-time sensor information indicating the status of the jet footprint that creates the free-form surface. Based on this information, the module adjusts the water jet. The machine uses information generated while milling to refine and update the process for future tasks.

© 2012 Penton Media, Inc.