“Composite Materials” is one of the core modules for the third year students at Queen Mary Engineering School, NPU. Started from the development history of the composites, this module covers all aspects of knowledge in composite materials, ranging from design, manufacturing, to performance and applications, providing a comprehensive training to students. The students will develop a good understanding of the role of composites in modern engineering during this module.
Due to the unprecedented pandemic of COVID-19 this year, the leading module organiser Dr. Han Zhang at QMUL can only deliver this module remotely via the online teaching platform this semester, facing many new challenges in teaching this core module with many theoretical and practical components. To ensure a good engagement level from the students during the live streaming sessions, Han utilises many vivid examples from daily life to facilitate the understanding of various concepts. For instance, although it was not possible to show the real components like carbon fibre reinforced composite at home during the lockdown in London, Han took a banana (skin) to explain the concept of anisotropic performance in composites as well as the hierarchical reinforcement in natural composites. All these examples and concepts were very well received by students.
Clearly, the remote teaching mode has greatly affected the practical experimental sessions, especially considering the students have not been able to return to campus, with no access to professional equipment and raw materials at home. To overcome this challenge, Dr. Han Zhang has designed an innovative teaching plan, allowing students to perform experiments at home without needing any professional equipment while practice and demonstrate the knowledge in composites from design, preparation, testing, to data analysis and interpretation.
To complete this specifically designed home based experiment – "Ice-Composites", the only required “equipment” is a fridge which is accessible at everyone's home. The real challenge, also the focus of learning in this practical, is the understanding of composites and the capability to design, select appropriate materials, predict and measure the properties, and utilizing learnt knowledge to analyse the obtained results from homemade ice-composites. Ice-based composite materials have demonstrated excellent performance with many applications during the World War II. The Royal Navy successfully developed lignocellulose-reinforced ice-based composite materials to produce bulletproof materials that can replace concrete and steel plates to protect ships and personnel. The design of the aircraft carrier was also proposed based on ice-composites(Project Habakkuk). In this home based experiment, Han askes students to fully demonstrate their understanding and creative thinking of composite materials by designing and performing their ice composites practice at home, together with data collection and analysis based on learnt knowledge in this module.
Although it seems a rather simple task to add something in the water and freeze it to test, this practical provides students the opportunity to design their own composites, select appropriate reinforcement in various forms and shapes, and conduct sample preparation and testing at home. Great potential and flexibility are provided for students to play with their ice-composites, demonstrating their understanding and creativity in composite materials. This practical has not only realized the possibility of home experiments for students, overcoming the issues of lack of access to professional materials and equipment, but also allowed students to better understand the theoretical knowledge from this module and obtain the practical hands on experience with fun.
Before performing the experiment, the students conducted group discussion and proposed various design schemes, followed by materials screening and selection locally to tailor the design parameters such as the type of reinforcement, fibre/particulate contents, length and orientation of the fibre/tape, as well as different fibre surface treatments. After the brainstorming sessions, the team members designed a variety of experimental schemes and material parameters, with many creative and fancy designs developed. For instance, adding synthetic fibers of textiles or creating hybrid composite materials, adding food like noodles as reinforcing fibers, or even adding cellulose from toilet paper, newspapers, etc. Since the toilet tissues were once in great shortage in the UK during current pandemic, Dr. Han Zhang who is still in London was commenting that students are really showing off the fantastic supply chain in China.
After the experimental plan was designed, the students actively participated and engaged in conducting the experiments. Mechanical testing like three point bending and impact resistance measurements were performed by using simple household items such as weighing scales, ropes, buckets, hammers, etc. For the technical problems students have encountered during the process, Han answered specific questions from each group individually during the online sessions, and summarised many common problems for the complete cohort to ensure a smooth running of their home experiments and their learning process in composites.
After the online session to address encountered questions, the students were more devoted and enthusiastic in conducting the experiment. From the design schematics to summarised comparison table based on the obtained results, all of these aspects are the evidence of a joint effort from everyone in the group. "A Song of Ice and Fire" has been conducted by the students, with the freezing Ice-Composites combined with their passion and enthusiasm.
This “Ice-Composites” home experiment fully utilises the available resources and items that students can access at home, with the online video conferences to overcome the obstacles like the team members cannot meet in person. A combination of rigorous knowledge learning and practical exercise at home has been successfully achieved based on this home lab activity, with many creative materials design and innovative testing methods developed by students. This innovative “Ice-Composites” home lab activity provides a platform for students to fully explore their great independent thinking and develop their problem solving capabilities, providing a brand new route for online experimental activities under current pandemic without compromising any learning objectives.
Written by/Yan Fei，Qi Yue
Picture credits/Yan Fei，Students
Audit/Kong Jie
