Does the fact that is black mean there won’t be any splashback? I.e. does it totally absorb IR?
If so does it get hot?
Is there a risk the blackness will get engraved off?
Normally crumb trays are made from aluminium that reflects IR and is thermally conductive. I assumed this was to make it immune to being struck by the beam but it does reflect IR giving splash back. Steel is quite a poor conductor of heat so could get hot locally.