I understand that steel is not a good material for antenna wire, but let's consider that I'm using the wire for purely structural support, or I am cladding it with copper to address the RF conductivity issues.
Then, which material is more suited to being strung between two supports? It seems to me there is a balance between at least two main concerns:
- the wire should be strong, so it doesn't break
- the wire should be light, so it has to support less of its own weight
To a lesser extent, cost may be a factor, although both steel and aluminum are affordable enough that it may not be an issue.
What material properties are relevant to this application? (Remember: purely structural concerns, not electrical.) Can we put some numbers and proper engineering to it?