If Iron-man sacrifice in Avenger

1.Spider man.              As Iron-man’s adopted son,he is the most likely to successor Iron-man.In Avengers 3:infinity war,his strength increased very fast.After so many punches from Thanos,he actually can stand up and fight!Have to say,his resistance is really strong.

If Iron-man sacrifice in Avengers 4,who will replace him?

2.War machine            He’s one of Iron-man’s best friend,He also has a armour like iron man. Remember in America 3,when he falls out of the sky,Iron-man is the one who rushes the first to save him,although he breaks his leg.

If Iron-man sacrifice in Avengers 4,who will replace him?

But either way, it's all up to the director to decide, and these are guesses.

If Iron-man sacrifice in Avengers 4,who will replace him?