what version/service pack are you using?
i just checked 2013 sp2.0 and it isn't available for parametric optimization (parameter study in 2012 and below) but it is available for parameter sweep studies. so you could do what you are describing pretty quickly in 2013.
if not, your best bet is to setup your problem, clone the project, change the materials and use batch run to run them over the weekend and review the results. with parameter sweep (what if studies in 2013), the benefit is that it would create those configs for you and output the basics in a table at the end.