6/14/17: Prof. Lee gives a talk at SEM meeting

Society for Experimental Mechanics  2017 Annual Conference in Indianapolis

Microscopic Ballistic Measurement of High-rate Dynamic Behavior of Materials

Jae-Hwang Lee1*, Wanting Xie1,2
1Department of Mechanical and Industrial Engineering, University of Massachusetts, Amherst, Massachusetts 01002, USA.
2Department of Physics, University of Massachusetts, Amherst, Massachusetts 01002, USA.
*E-mail: leejh@umass.edu

Extreme materials science related to ballistic impacts is crucial for certain industrial applications, as well as defense applications. Due to the experimental difficulties in performing supersonic ballistic experiments at the micro-scale, numerical simulations have primarily been used to study extreme materials science at the micro-scale. However, due to insufficient information of materials’ characteristics at high-rates (HR), accurate experimental results, which can be directly compared to numerical simulations, are desired.

My group has developed a microscopic ballistic technique called advanced laser induced projectile impact test (α-LIPIT) to provide the HR ballistic characteristics of various materials ranging from conventional materials to novel nanomaterials. In this talk, I will introduce our recent progress on the HR study using α-LIPIT with several materials including aluminum particles, Kevlar fibers, and graphene-polymer composites. Highly-controlled single micro-sphere impact experiments are carried out and the ultrafast optical microscopy, which utilizes femtosecond laser pulses, enables precise quantification of the micro-sphere’s motion during the supersonic collision events. Based on the tracking of the projectile motion, the real-time force applied by the projectile is also explicitly defined.