Claims can be written in metal materials or rubber materials.

Your range is big enough. Elastic materials can include elastic materials such as rubber, and metals generally cannot be called elastic materials. If you use such a wide range of materials, I don't think materials should be the focus of protection, and the people behind them can't simply drill holes to get authorization. In short, when writing, try to write the known schemes (unless you want to keep them confidential as technical secrets) into the specification, and the patent claims will try to summarize the same characteristics of these schemes abstractly, and attach some progressive rights to the abstract claims.