EUROPEAN CONGRESS AND EXHIBITION ON ADVANCED MATERIALS AND PROCESSES - EUROMAT 2021

Since the beginning of systematic materials science, researchers have been aiming to combine high strength with ductility, maximizing the overall mechanical performance and damage tolerance of a material. The well-known strength-ductility paradigm makes it impossible to achieve these properties in a homogeneous material. However, heterogeneous materials, such as nanocomposites, are a promising approach to this problem, as they can combine properties of their constituent elements and offer a vast amount of interfaces for modification in between. This can lead to unique material property combinations. In this work, W-Cu nanocomposites, merging the high strength from the nanostructured W phase with the enhanced ductility through the softer Cu phase, were fabricated using high-pressure torsion. Additionally, the interfaces were modified via doping with specific impurity elements, found by density functional theory to raise interface cohesion, with the goal to improve fracture toughness and damage tolerance of the composites. Material batches with varying W and Cu fractions and additional ab-initio informed doping with interstitial and substitutional interface-strengthening elements are mechanically characterized utilizing various in-situ small-scale testing techniques, exploring the limits we can push such nanocomposite materials in an effort to overcome the strength-ductility paradigm.