Dr. Vi Kie Soo

Research Fellow

Australian National University

Vi Kie Soo graduated with honours in bachelor of engineering with major in Electronic and Communication Systems from the Australian National University in 2012. In 2013 she commenced her Ph.D. study at the Australian National University, funded by AutoCRC research program, on Life Cycle Impact of Different Joining Decisions on Vehicle Recycling, and has submitted her Ph.D. thesis in September 2017. Her PhD was awarded in Jun 2018 and she is currently a Research Fellow funded by the ARC Training Centre in Lightweight Automotive Structures (ATLAS) at the Australian National University. She has published 13 research papers to date wherein she is the first author for 10 of them. Her research interests include Life Cycle Assessment, System Dynamics, Eco-design, Life Cycle Engineering, lightweight materials, advanced joining techniques, end-of-life vehicles and e-waste. She has engaged in a number of field studies in collaboration with industry and other universities. Researching on issues pertaining to the manufacturing and recycling sectors through industry engagement has always been her passion and she is keen to continue research in areas relevant to sustainable manufacturing.

Life Cycle Impact of Different Joining Decisions on Vehicle Recycling

Stricter vehicle emission legislation has driven the significant reduction of carbon dioxide emissions during the vehicle use phase. This is achieved through the increasing use of lightweight materials and multi-material concepts to reduce the vehicle mass. To account for the complexity of multi-material vehicle designs, the choice of joining techniques used is becoming more diverse. Moreover, the different material combinations, and their respective joining methods play an important role in determining the potential of full material recycling in a closed-loop system.

This thesis evaluates the types of joining technologies used in the automotive industry and identifies those that hinder end-of-life vehicle (ELV) recycling based on industrial trials carried out in Australia and Europe. Through the case studies, observations on the characteristics of joints that lead to impurities and valuable material losses for different recycling processes are examined. Life cycle analysis is performed highlighting the presence of impurities during ELV recycling phase that is not well captured in current studies. The System Dynamics approach is then used to illustrate the gap between the changing vehicle designs and the long-term effects on material recycling from the life cycle perspective. Based on the observations from case studies, the dynamic behaviour of the vehicle recycling systems can be described using two widely known system archetypes: “Fixes that Fail” and “Shifting the Burden”.