Material criticality definition diagnostic and two proposed concepts
Résumé
The term “critical raw materials” or “criticality” just separated recently from other similar notions for instance “strategic”, “shortage”, or “important”. Even though this is a novel research area, it drew a lot of attention, especially to the governmental institutes. Among the existing reports of critical materials, none of them showed an in-depth analysis of how to define the critical materials or the criticality. The most well-known version of critical materials explanation is to face high supply or environmental risk and to be of high economic importance[1]. However, an official definition or the deduction of current explanations is lacking. Due to the lack of diagnostic of criticality impact factors before definition, the current methodologies are either too subjective, or not comprehensive enough. Furthermore, there is no methodology for a specific industrial sector. With those issues in mind, the purposes of this study are to do a comprehensive and in-depth diagnostic for the definition of criticality or critical materials; to provide a more robust quantitative criticality assessment methodology; and to zoom in at one specific industrial sector level. For the diagnostic of criticality, the economic, technological, social, political, geographical and environmental aspects will be considered. The different parameters and sub-parameters under each aspect will be indicated while several parameters or sub-parameters are related to more than one aspect. Another part of the diagnostic is about variables like when, who, where, dynamic changes etc. i.e. different subjects in different places during different times make different results of critical materials under different situations. To sum up, only with the consideration of every aspect and variable, a comprehensive definition can be proposed which can lead to a robust methodology able to determine critical materials. In terms of methodology, the current methodologies are almost based on the same basic concept developed by the National Research Centre[2]. Some studies[3][4] added another axis. The first concept proposed by this study is based on a three-dimension but with an extension of time which allows the integration of dynamic aspects. The scale will be continuous so that the results are more precise. The criticality is determined by the distance between the position of one materials and the origin and by the angle between the point and the critical line. This concept allows a visualisation of critical relationship between two materials and a quantification of criticality order. The second proposed concept here can be figurative to a balance. The criticality is based on the imbalance between the demand and supply. The demand and supply’s weights are both influenced by the aforementioned aspects. These weighting relations will be quantified by indicators of corresponding parameters. The way the “balance” behave is influenced by the variables defined in the definition diagnostic part. The tilt degree toward the demand side represents the criticality. The first proposed concept is suitable for determining the criticality order of a list of materials while the second concept is more suitable for determining whether a material is or will become critical or not.