Actuators fabricated of silicon and titanium-nickel thin film deliver large force and stroke compared to other means. These devices are electrically powered at transistor-transistor level voltages. Rapid cycling is possible because of the large surface area to volume ratio, and actuators have been cycled tens of millions of times without fatigue failure. Surface finish of sputtered film is superior to bulk material, and biocompatibility is high. Thin film TiNi is a challenging new material for MEMS.

The shape-memory phenomenon is described and a brief history of applications is presented. SMA thin film fabrication, function, and final application in valves, relays, optical switches, and medical intra-vascular stents and filters are described. Advantages and characteristics of shape-memory actuators, and limitations and problems of fabrication of shape-memory alloy thin film, are discussed.

About the Speaker: Dr. Johnson received a BS degree from the South Dakota School of Mines and Technology in 1953, and a Ph.D. from the University of Hawaii in 1972 in physics. He is founder, director, and president of TiNi Alloy Company where he manages a research team engaged in development of products using shape-memory alloys. Over the past ten years he has worked on the development of miniature circuit breakers and relays, tactile feedback devices for computer interfaces, non-explosive separation devices for space applications, and microvalves using thin films of TiNi shape-memory alloy.

Time:

6:00 - 7:00 p.m. "No-host" cocktails

7:00 - 8:00 p.m. Dinner

8:00 - 9:00 p.m. Presentation

Cost:

$20.00 Members

$25.00 Non-Members

$10.00 Students

Entrees:

Fresh seasoned red snapper in garlic mushroom sauce or

Broiled marinated chicken kabob.

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