Method and system for designing a material

A method of designing a material by optimising values for a plurality of design variables, the method including the steps of:

• (i) providing one or more property models, the ith property model (where i is an integer from 1 to nprop, the number of property models) producing a prediction Pi for a value of a respective property of the material as a function of the design variables, and further producing a value for the uncertainty σi in the prediction Pi,
• (ii) for each property, setting a specification target T0,i for a desired value of the property and a probability pi for that specification target T0,i to be met or exceeded,
• (iii) for each property, determining a probabilistic target Ti for a value of the property, the probabilistic target Ti being based on the specification target T0,i and the probability pi, and further defining a merit index factor Gi based on the degree to which a given prediction Pi satisfies the probabilistic target Ti,
• (iv) constructing an overall merit factor G from the individual merit index factors Gi of the properties, and
• (v) determining a set of optimal design variables that optimise the overall merit factor G.