yes it's allowed provided that it will fit through the x-ray. i would just package it well and put it in a bin during the x-ray to keep the luggage pile up at the end from crushing it.

we had some glass panels cut for nightstand table tops and carried them on. they were packaged well in cardboard and taped shut. no issues with TSA.

on board, i think we asked the FA to put in a coat storage so it wouldn't be crushed in the overhead.