Elizabeth, no you can't. "Deadbeat“ refers to someone who does not pay his debt. Examples 1) He is a deadbeat debtor who does not pay his credit card bills. 2) He is a deadbeat dad (referring to a divorced dad who does not pay child support 不付 赡养费）

Yeah I am actually wondering that if it's a rarely used term. It's grammatically good, dead is an adverb means completely and beat here as an adjective means tired but I'm not sure if it's a fixed phrase.

yes you can, but it's informal language dead beat means exhausted or tired out

usually, you would say either "I'm dead tired..." or "I'm beat..." "Dead" and "Beat" are really two separate colloquialisms for tired or exhausted. You would have to say it with a long pause between the words or it would be mistaken for "deadbeat". Brandon is right- "Deadbeat" is slang for lazy, Synonyms are "bum" "slacker", and to some extent "hippie".

it is also a new phases for me !dead beat ! i am dead beat when guiding you to visit the city all day !