piece of material vs piece of cloth

piece of material and piece of cloth both are nouns.

Word	Noun	Adjective	Verb	Adverb
piece of material	Yes	No	No	No
piece of cloth	Yes	No	No	No

As nouns, piece of material and piece of cloth are synonyms defined as:

piece of material and piece of cloth: a separate part consisting of fabric

piece of material (noun)	piece of cloth (noun)
a separate part consisting of fabric	a separate part consisting of fabric