Boron Nitride Nanotube Reinforced Metal Matrix Composites

Boron Nitride Nanotube (BNNT) displays remarkable mechanical properties (elastic modulus and tensile strength exceeding 1 TPa and 60 GPa, respectively) and brilliant thermal endurance (capable of withstanding temperatures as high as 700-900°C without degrading or oxidizing). This makes BNNT an ideal reinforcement candidate for developing strong and lightweight nanocomposites. This research seeks to integrate BNNT in Aluminum, Magnesium and Titanium matrices to enhance their mechanical properties. Spark plasma sintering and solidification processes (casting, ultrasonic cavitation and plasma spray) are being adopted. In-situ mechanical techniques are being employed for real-time examination of strengthening mechanisms in these nanocomposites.

Directionally Aligned Nanotubes Acting as Crack Bridges in Al-BNNT Composite

Wetting and Filling of Nanotubes by Molten Aluminum during Equilibrium Solidification

Splat Sliding in Cold Sprayed Metallic Coatings

Cold sprayed coatings are composed of splats as their building blocks. Relative sliding between the splats can lead to deterioration of mechanical properties. This project seeks to examine the splat sliding behavior by in-situ mechanical investigations under a scanning electron microscope for real time visualization of deformation behavior. The splat sliding behavior is dependent on splat geometry, porosity, oxide content and inter-splat bonding. This project aims to establish correlation between processing conditions, coating microstructure and mechanical properties, and to understand the role of post-processing heat-treatment on arresting the splat sliding. In-situ techniques such as flexural tests, nanoindentation and nanoscratch in conjunction with Digital Image Correlation (DIC) analysis approach are adopted for visualizing the deformation mechanisms in cold sprayed microstructure.

Microstructural strains determined by in-situ testing inside electron microscope

In-situ testing of cold sprayed metallic coating inside SEM chamber

Graphene Foam

Researchers at the Plasma Forming Laboratory are focusing on the development and characterization of the next generation high-performance Graphene foam (GrF) based composites. The three-dimensional cellular structure in GrF conserves most of graphene’s remarkable properties while offering seamless pathways for mechanical, electrical and thermal transport. Our lab is interested in exploring the multifunctionality that the hierarchical structure of GrF provides to develop lightweight composites with enhanced strength, impact resistance, and sensing capabilities. Research efforts at the PFL include probing the performance of GrF based composites in areas of energy, mechanics, deicing, electromagnetic shielding and health. Studies include the nanoengineering of GrF –polymer interfacial surfaces, and the understanding of fundamental deformation features proving enhanced thermal, electrical and superior load-bearing abilities.

Scanning Electron Micrograph of free-standing three-dimensional Graphene Foam

3D Graphene Foam hollow branch with open cell structure

Ultra High Temperature Ceramics

Ultra High Temperature Ceramics have been of great interest in the aerospace and aeronautic industry due to the high melting point, and due to their potential application as a protection material for the stagnation areas of leading edges in supersonic vehicles. At the Plasma Forming Lab, researchers are working on the development of the next generation of UHTC’s. Space exploration will have to be reusable, that is one of the main goals on the development of new UHTC’s: durability. With new UHTC’s that will be able to stand multiple reentries from orbital speeds to our atmosphere, man will be able to accelerate space exploration due to the reduction in resources needed to keep exploring. 

Scanning Electron Micrograph of UHTC

Ultra High Temperature Ceramics: one of the key components of space exploration

2D Materials

Two-dimensional (2D) materials are challenging the world of material science since the discovery of graphene. 2D materials exhibit interesting properties which arises from their unique bonding nature, resulting in potential multifarious applications such as electronic devices (sensors, field effect transistors), optoelectronic devices (photodetectors, light emitting diodes), solid lubricants and functional composites. Despite their varying applications, fundamental understanding of 2D materials in the bulk form still remains elusive with respect to their bonding directions, which would expand their emerging applications. In PFL, we delve into the bulk multiscale mechanical and tribological properties of sintered bulk 2D materials along the different bonding directions. Further, we understand the fundamental deformation mechanism of bulk 2D materials in real-time by in-situ techniques. 

Scanning Electron Micrograph of MXene

BNNS – Boron Nitride Nano Sheets