Continuous bending under tension (CBT) is a sheet metal forming process during which a material is repeatedly passed through a series of rollers. CBT has been observed to significantly increase a material's elongation to failure (ETF), meaning the material will stretch further before breaking. This process ultimately improves the formability of sheet metal at room temperature, making metals stronger and lighter without the need for more expensive heating processes. Digital image correlation (DIC) is a non-contact optical method used to measure the deformation of a material subjected to a load. This research aims to determine if DIC can be used to measure through-thickness strain in CBT specimens at the microscale. Micro-DIC was used to measure strain in titanium samples. To do this, a DIC pattern was applied to the edge of each sample using a microstamp. Pictures were taken of the stamped region throughout the CBT process using a variety of imaging methods, including cameras and optical microscopes. The strain in the sample was then calculated by tracking the displacement of the pattern across images. From initial testing, we can conclude that microstamping for through-thickness DIC can be used to successfully measure the strain of CBT specimens at the microscale. This new methodology can be used in a wide variety of applications. In CBT experiments, micro-DIC allows us to study local deformation, which is critical in determining how CBT increases a material's ETF. More generally, micro-DIC is a relatively accessible method that can obtain extremely detailed strain data.
University / Institution: Brigham Young University
Format: In Person
SESSION D (3:30-5:00PM)
Area of Research: Engineering
Faculty Mentor: David Fullwood
Location: Alumni House, SORENSON ROOM (3:50pm)