Researcher(s)
- Jeremiah Glavin, Mechanical Engineering, University of Delaware
- Anna Freund, Mechanical Engineering, University of Delaware
Faculty Mentor(s)
- Chelsea Davis, Mechanical Engineering, University of Delaware
Abstract
Characterization of materials is essential for determining whether a material is suitable for a specific application. Mechanical characterization is often combined with imaging techniques such as microscopy. However, conventional testing frames typically use a single actuator, which can cause the region of interest to drift outside the microscope’s field of view during testing. To address this limitation, the PIM Lab developed the Stress Testing Rig with Dual Actuation for IN-Situ Imaging (STRAINI). This uses two piezoelectric motors to provide nanometer-scale positioning while the test sample undergoes deformation. To optimize the system, I performed a cost-benefit analysis of different motor options. The motors are the focal point of this build which allow for dual actuation and therefore require a more extensive look into, step size, resolution, software and hardware integration, as well as life span and affordability.Our research team has no affiliation with the motor manufacturers; therefore, the motors are identified anonymously in this comparison. Motor Type A (MT-A), which is currently used in STRAINI, is the more expensive option but provides the highest resolution at 6 nm. Motor Type B (MT-B), produced by another manufacturer, is more affordable and provides a resolution of 25 nm. Although MT-B was sufficiently precise for our testing requirements, we experienced difficulties with its reliability and with controlling its displacement rate. These limitations ultimately became the deciding factors in our evaluation. Although multiple motor options may be appropriate for similar systems, our results indicate that MT-A is better suited for STRAINI because of its repeatability, resolution, and control. These piezoelectric linear stages will continue to support micro-mechanical testing in combination with advanced microscopy, enabling more accurate in-situ characterization of materials.