A team of researchers from the Graduate School of Organic Materials Science at Yamagata University, led by Professor Tetsuo Takayama, Quan Jiang, and Professor Akihiro Nishioka, has developed an advanced model for evaluating the impact energy dissipation in short fiber-reinforced thermoplastics. This work, published in Polymers, highlights how such materials, especially when used in transportation sectors like automotive and aerospace, play a significant role in reducing greenhouse gas emissions by replacing heavier metallic components.
The study emphasizes the importance of short fiber-reinforced thermoplastics in reducing carbon dioxide emissions, particularly in household vehicles and aircraft, where weight reduction is key. The researchers explain that while carbon fiber-reinforced plastics have been used in high-end automobiles and aircraft, their high cost limits widespread adoption. In contrast, short fiber-reinforced thermoplastics offers a more cost-effective alternative, making it an attractive material for practical applications such as car body components.
Professor Takayama, Quan Jiang, and Professor Akihiro Nishioka focused on the impact resistance of these materials, a critical property for ensuring safety in transportation. “In our study, we aimed to model and predict the notched impact strength of short fiber-reinforced thermoplastics products, which is crucial for understanding how these materials behave under stress,” said Professor Takayama. Using a combination of experimental and theoretical approaches, they were able to create a quantitative model that closely matches real-world results, providing a reliable method for predicting the mechanical performance of short fiber-reinforced thermoplastics materials.
The results of their study show that the orientation of the glass fibers within the thermoplastic matrix plays a vital role in determining the impact strength. Shorter fiber lengths, which occur due to the injection molding process, tend to reduce the overall strength of the material. The researchers found that optimizing fiber orientation and length distribution could significantly enhance the impact resistance, making short fiber-reinforced thermoplastics more durable in high-stress environments like vehicle collisions.
The Professor Takayama ‘s research also uncovered that fiber-matrix interfacial shear strength is a critical factor governing the mechanical performance of these materials. “Our model revealed a strong correlation between fiber-matrix interfacial shear strength and impact strength, which could be applied to a wide range of fiber orientations and lengths,” explained Professor Takayama. The team’s findings have important implications for the future design of lightweight, high-performance materials in the transportation sector.
In conclusion, the study provides an in-depth understanding of the mechanical properties of short fiber-reinforced thermoplastics and offers a reliable model for predicting their impact strength. As global efforts to reduce carbon emissions intensify, materials like short fiber-reinforced thermoplastics could play an increasingly important role in achieving sustainability goals by reducing the weight and improving the safety of vehicles.
Journal Reference
Jiang, Q., Takayama, T., & Nishioka, A. (2023). “Impact Energy Dissipation and Quantitative Models of Injection Molded Short Fiber-Reinforced Thermoplastics.” Polymers. DOI: https://doi.org/10.3390/polym15214297
About the Author
Quan JIANG is a PhD candidate from Department of Organic Materials Science Yamagata University. He obtained a Bachelor of Engineering degree in 2018 (from Heilongjiang Institute of Technology, major in Mechanical Design, Manufacturing and Automation). He has been a structural design engineer of composite drive shaft at China Taian Composite Materials Facilities Co., Ltd., from 2017 until 2019. During this period, he developed a strong interest in composite materials, particularly in the interface that determines the design of composite structures. Since October 2020, filled with curiosity about the study of interface strength in composite materials, he began pursuing his master’s and doctoral degrees at Yamagata University. During his degree studies, he proposed an interfacial shear strength (IFSS) evaluation method based on short beam shear tests. This method directly measures the IFSS of fiber-reinforced thermoplastic (FRTP) injection-molded product s by inducing high shear stress through the shortening of the distance between the support points in a three-point bending test. Based on the high-precision IFSS measured by this method, he further proposed a quantitative model for FRTP notched Charpy impact strength. He has authored and co-authored six publications that have been published in international peer-reviewed journals. His fields of interests include: interfacial shear strength, fiber-reinforced thermoplastic, notched Charpy impact strength, solidification temperature and injection molding. His research vision is to contribute to the development of environmentally friendly and tough composite materials.
