06/04/2021
By Sokny Long

The Francis College of Engineering, Department of Plastics Engineering, invites you to attend a doctoral dissertation defense by Fabian Ullrich on “New Ceramic-Based Layered Composites for Transparent Armor.”

Ph.D. Candidate: Fabian Ullrich
Defense Date: Thursday, June 17, 2021
Time: 3 to 5 p.m. EST
Location: This will be a virtual defense via Zoom. Those interested in attending should contact Fabian_Ullrich@student.uml.edu and committee advisor, davide_masato@uml.edu, at least 24 hours prior to the defense to request access to the meeting.

Committee Chair (Advisor): Davide Masato, Ph.D., Assistant Professor, Plastics Engineering, UMass Lowell

Committee Members:

  • David Kazmer, P.E., Ph.D., Professor, Plastics Engineering, UMass Lowell
  • Jay Park, Ph.D., Assistant Professor, Plastics Engineering, UMass Lowell
  • Alireza V. Amirkhizi, Ph.D., Associate Professor, Mechanical Engineering, UMass Lowell

Brief Abstract:

Current transparent materials for lightweight and high impact resistance are only able to withstand a moderate number of threats. This work focuses on sapphire-based layered composites to increase the level of protection for such applications. The dynamic behavior of sapphire and constitutive properties of polycarbonate, the materials involved in the composite layers, are characterized under relevant conditions. Then, manufacturing and lamination of flat sapphire/polycarbonate samples is studied, and a protocol is developed to evaluate transparency and impact properties. A numerical model is developed and calibrated based on experimental results, allowing evaluation of potential designs not considered in the experimental work. The research work focuses on the manufacturing process of polycarbonate, the approach and testing of sapphire/polycarbonate lamination, and the ballistic modeling. The research work is divided into three main work packages. First, the influence of different manufacturing methods is studied to optimized polycarbonate dynamic mechanical properties. Second, the effect of layer thickness and lamination of sapphire/polycarbonate composite is tested for ballistic performance. Third, a computational model is applied to study the interaction between the layers, complex geometries, and optimization.

The proposed research produces significant advancements in the field of transparent composite manufacturing. The design, manufacturing, and lamination, of composite materials with high-impact properties has the potential to advance light weighting for several applications. The study of the effect of manufacturing process on polycarbonate dynamical resistance, allows understanding of processing effects on molecular orientation and thermal history. The development of a lamination procedure will establish the methods to guarantee composite integrity, transparency, and functionality. The approach used for the modeling of the ballistic impact expands the knowledge in the field of impact resistance criteria, and composite modeling. The approach to modeling impact resistance of curved composites will open up new opportunities for new geometrical design. Overall, the results of this research have direct impact in the development of face shielding for military and civil applications. The possibility of having light weighting eye wear protection that guarantee high-impact resistance and transparency, will improve market accessibility and safety for users.

All interested students and faculty members are invited to attend the online defense via remote access.