Novel Approaches on Interface Strengthening between Metal Surface and Polymeric Material

Collaborative Research Program 2023-2025

One of the effective approaches in reducing emission from transportation industry is improving fuel efficiency by reducing their weight. Fibre metal laminates (FMLs) are structural materials which are distinguished by high stiffness-to-weight and strength-to-weight ratios. They possess outstanding fatigue resistance, excellent impact strength, high fracture toughness, and remarkable corrosion and moisture resistances. In addition, FMLs are inexpensive and well-established in manufacturing with low maintenance costs. They are hybrid composite materials comprising thin metal sheets and layers of fibre-reinforced polymers. Their properties and failure characteristics can be tailored according to the type of metal, fibre and polymer, the volume fraction of fibre, and their stacking order and direction. This explains the high demand of FMLs in advanced industries such as aerospace and automotive industry. Owing to their outstanding mechanical strength and lightweight advantages, FMLs offer not only significant reduction in fuel consumption and thus gas emissions, but also long service life for key components in the corresponding structure. Besides in fighting aircrafts, it promotes their manoeuvring capability and flight time.

OBJECTIVE 1. Understand mechanism of chemical bonding at polymer-metal interface. Dissimilar materials are less likely to form chemical bonds. Surface of each material, however, can be modified to contain bonding sites that enable chemical bonding at the interface. Metals have low ionization energy; meaning that they have high tendency to be oxidized. In principle, if a non-metal surface is modified to have oxidizing groups, it is expected to chemically bond with the metal surface through oxidation. This study will investigate the effects of surface chemistry on bonding of dissimilar materials while providing new knowledge and understanding of chemical bonding at polymer-metal interface.
OBJECTIVE 2. Understand mechanism of mechanical bonding at polymer-metal interface. Mechanical adhesion is caused by interlocking of the two materials at the interface. In a soft-hard material system (e.g. polymer-metal), the filling of the soft material in cavities and pores of the hard material is important. Therefore, the presence of nano/micro-features on the surface has paramount impact on the strength of such mechanical bonds. Effect of controlled surface textures on the metallic surface on forming mechanical bonds with the polymer layer will be studied.
OBJECTIVE 3. Investigate effects of interfacial bonding on macroscale mechanical properties. This study will evaluate the mechanical and chemical means of controlling the interface and understanding their effectiveness in manipulating mechanical properties of fibre metal laminates (FMLs).

Kazakhstan is a country that owns long experience in aerospace industry; the proposed project will result in developing a new generation of fibre metal laminates with engineered and tailored mechanical performance. It will bring research opportunities to undergraduate and postgraduate students from both Kazakh and international backgrounds. The proposed project will disseminate new knowledge, demonstrate new technology, and entice the next generation of engineers and scientists at the Kazakh community. Thereby, they would be inspired and equipped with knowledge for start-up manufacturing plants to develop polymer-metal composites for automobile and aerospace industry.