Force Characterization of Different Metal Thicknesses Using Laser Folding

Researcher(s)

  • Joshua Hyman, Electrical Engineering, University of Delaware

Faculty Mentor(s)

  • Nathan Lazarus, Electrical and Computer Engineering, University of Delaware

Abstract

Machinery deployment in difficult environments needs improvement. Latches, and motors are susceptible to failures, which may not be easily corrected in space. Expensive crafts such as telescopes and satellites, can become useless if one of these mechanisms fail. A process known as laser forming may solve this problem. Laser forming involves folding and bending workpieces with a passing laser. Traditional forming methods such as rollers and press brakes use cold metal, which causes the workpiece to return slightly to its original shape.  Laser forming prevents this because the metal is denatured and keeps its new shape when cooled. When folded, workpieces can generate force on other surfaces. In the experiment performed, a .004 inch strip of 316 stainless steel was folded against a load cell which changes voltage when forces act upon it. By measuring the voltage after different amounts of passes with the laser, the forces produced by the 0.004 inch thick were characterized. There was a linear relationship between voltage and the passes. The load cell read 0.217mV at zero passes and after 55 passes it read 0.044mV, which translates to approximately 0.052 newtons of force. Consistent test strips were also developed for different thicknesses while avoiding warping and oxidation. It was found that setting the laser to 30 watts and 852mm/s gave the best results. The next step in this research is to fully characterize the forces for each thickness. Using these results, another experiment to identify how much mass each thickness can support while folding can help apply laser folding in a deployment process, which would be helpful for complex parts and situations mentioned before such as space travel. In environments where expensive equipment can be lost due to the smallest of failures, new methods to reliably deploy machinery are indispensable.