Toward Tough Glasses with Controlled Nanoscale Heterogeneities

ended

Specialty glass manufacturing is annually a €30 billion industry worldwide and transparent oxide glasses are one of the most important engineering and functional material families owing to their unique features, such as tailorable physical properties. However, at the same time, intrinsic brittleness continues to be their main drawback, which severely restricts many applications. In the proposed project, we will explore the possibility to improve the fracture toughness and damage resistance of oxide glasses through controlled nanoscale phase separation, as the presence of inclusions can lead to crack deflection or trapping. The size of these heterogeneities needs to be small enough (<50-100 nm) to maintain transparency. To this end, we will tune the composition of calcium aluminosilicate glasses to enable controlled phase separation with respect to the size and composition of the nano-domains (Work Package 1). Then selected mechanical properties (stiffness, hardness, fracture toughness, and crack resistance) of these new glasses will be explored (Work Package 2). These experiments will be guided by a combination of atomic scale (molecular dynamics) and microstructural scale (peridynamics) simulations (Work Package 3). The project will provide the scientific breakthrough for elucidating the toughening mechanism induced by phase separation and its impact on macroscopic crack propagation. The complementary expertise of the applicant and supervisor and the research and training environment provided by the host organization (Aalborg University, Denmark) will ensure the achievement of this timely and innovative project as well as the dissemination and exploitation of the expected results. These research outputs will accelerate the design of new fracture-resistant glasses, which can be used in various fields. The applicant will emerge from the project with new skills, and the capability to launch her own research group.