April 15, 2025
Jin Yang, an assistant professor in the Department of Aerospace Engineering and Engineering Mechanics at The University of Texas at Austin, was selected to receive a National Science Foundation (NSF) Faculty Early Career Development Program (CAREER) award for 2025.
Yang was awarded for his proposal, “Understanding Fracture Propagation in Soft Viscoelastic Materials from Slow to Ultra-high Strain Rates and at Different Temperatures.”
He will use the award over the next five years to investigate fracture propagation – the formation of cracks or fractures – in soft viscoelastic materials, such as polymers, hydrogels and biological tissues. These materials are used in a wide variety of engineering and biomedical applications including laser eye surgery, breaking up kidney stones, drug delivery and traumatic brain injury prevention.
However, the fracture behavior of these materials is still not fully understood, particularly under extreme loading rates and temperatures, and current fracture models fail to address the complexity of 3D fractures in the materials.
Yang and his research group aim to bridge these gaps by developing integrated experimental and computational methods to provide a comprehensive, quantitative understanding of dynamic fracture behavior in soft, rate- and temperature-sensitive materials. Researchers on the team will tackle these problems by introducing state-of-the-art 2D and 3D full-field deformation (the distortion of a material under strain or stress) measurement techniques to quantitatively analyze fracture propagation of soft materials at different strain rates and temperatures.
Innovative experimental approaches of testing viscoelastic materials will include:
1) A variety of fracture testing methods in a nearly static, or quasistatic loading speed;
2) Needle-induced cavitation, which involves generating localized bubbles in soft materials by injecting gas or liquid;
3) Laser-induced inertial cavitation, where focused high-intensity laser pulses induce inertial cavitation within soft materials and trigger dynamic fracture at ballistic loading rates;
4) 2D Digital Image Correlation (DIC) and 3D Digital Volume Correlation (DVC) full-field deformation measurement techniques to measure the material’s displacement and strain fields (the motion and distortion of a material under strain or stress) by using imaging tracking algorithms to compare its undeformed and deformed states.
The research will also investigate the role of temperature and quantify how rate and thermal effects can be unified to describe fracture in soft materials. These experimental datasets will help Yang and his team to develop a comprehensive theoretical and computational framework that integrates low-rate and high-rate fracture phenomena.
The results of this research will support the development of more accurate models to predict the failure of soft materials, allowing for the advancement of critical applications in manufacturing, biomedical device design, structural materials for extreme environments and more.
“Understanding fracture mechanics in soft materials will inform the design of soft robotics and health devices to prevent fracture damage,” Yang said. “This knowledge is also critical for developing new aerospace materials that exhibit softening behavior at elevated temperatures. Moreover, being able to predict soft material failure under extremely high loading rates is also essential for improving the precision and safety of laser- and ultrasound-based medical procedures, such as laser lithotripsy for kidney stone removal and corrective laser eye surgeries.”
Besides its scientific objectives, this project will also provide a wide range of educational and outreach activities. These include undergraduate and graduate research opportunities, curriculum development, a student symposium, K-12 outreach and industrial and medical collaborations.
The NSF CAREER award is among the most prestigious offered to junior faculty, providing up to five years of funding to those who exemplify the role of teacher-scholars through outstanding research, excellent education and the integration of education and research within the context of their organizations' missions.
Learn more about Yang’s research.
