Why Materials Theory?

Abstract

© L p i Materials science is an interdisciplinary field with the broad objectives of understanding the structure and properties of materials and the discovery of new materials. In his historical account of this field titled The Coming of Materials Science (Cahn et al. 2003), R. W. Cahn referred to the middle of the past century as the time materials science was born out of metallurgy. Materials science has expanded since then to cover the science of ceramics, polymers, semiconductors, and numerous functional materials. Since the inception of materials science, experiment has been a central theme underlying investigation of the structure and properties of materials while modelling was aimed initially at the interpretation of experimental results. However, with the need to understand increasingly complex materials structures and the connection of materials structure with materials behaviour, advanced theoretical concepts from the fields of physics, chemistry, mechanics, applied mathematics, and statistics were introduced. Thus, the development of rigorous models for materials structure, materials defects, microstructure evolution, and the behaviour of materials became a second thrust of materials science. Over the past three decades, the theory of materials has worked hand in hand with experiments to interpret results and to explore materials behaviour under conditions that at present cannot be probed directly by experiments. Concurrently, materials research began to exploit the rapidly increasing power of computers to solve theoretical models and to generate structural and property related data through simulations. This in turn enabled materials discovery for applications, including batteries (Liu et al. 2015) and structural materials (Schmitz et al. 2011). The availability of advanced simulation tools capable of predicting the structure and behaviour of materials over varying length and time scales and the possibility of integrating such tools into materials design marked the coming of integrated computational materials engineering (ICME) (Integrated Computational Materials Engineering: A Transformational Discipline for Improved Competitiveness and National Security et al. 2008), an approach integrating simulation tools at all relevant scales for the concurrent design of materials, processes, and products. Furthermore, the quest for accelerated materials discovery has ushered in the era of the materials genome (MG), where experiments, computational tools, and big data (Materials Genome Initiative Strategic et al. 2014) are combined to accelerate materials discovery. Advances in computing, data acquisition, and the discovery and design of materials have also led to the application of the principles of informatics to materials (Rajan 2005), whereby information based on the structure and property of materials and their connections are surveyed to enable MGand ICME-type efforts. At this point in time, it is fair to state that materials research is driven by materials discovery and engineering. In this regard, understanding the structure of materials and