the metal strip or anything for that matter that goes at the bottom of doorways is called a threshold.
Doorway thresholds can be built from materials such as wood, stone and metal. You can get more information about doorway thresholds at the Wikipedia website.
That can be the carpet edging strip, the fastening strip, carpet plating strip for a few names.
The simple term for it is Schleutter strip. There are several variations, but genericaly that is what its called.
This is called Triboelectricity (tribo means friction).
the metal ring that covers the holes is called the 'Throat'
Ropes & Stanchions
There are metal covers for cell phones, patios, and carports. A metal cover for a cell phone can be purchased from eBay or a cell phone retailer. There are patio stores that offer metal cover awnings and there are even metal covers available for use as carports or recreational vehicle covers.
Stanchions
Metal can conduct heat away from your body (hands) faster than carpet.
This is called J Trim and you can purchase this from most building supply stores.
do covers of heavy metal songs
steel