In reply to Albachoss:
In most crampon useage you end up touching rock a bit, and you need the crampon points to stay reasonably sharp. If the material isn't hard enough to scratch the rocks, then presumably the rocks are going to be scratching them. Which would lead to very quick bluntening to the point that they wouldn't work well at all in hard neve or ice.
I don't know much about materials science though - maybe it's possible to have something that will keep its edge when contacting rock but won't scratch the rocks?