For the main body part, we decided to use the material like the one on spiderman, with net bump on it.
Final render for the main body. We took several photos (upper one),as reference, i collected many iron texrures for it then edit them in photoshop.
For the helmet part, i used overall bump map and standard one to make it looks like more layers and also more damaged.
The chest part is the most chanllenged part.Our original idea is:to make an organic heart for the character and also have a close up shot for the heart which we gave up finally.For a visual effect short movie, it's very necessaey to make all of the part as realistic as possible, but to be honest, we couldnt acheive the real heart result perfectly and we dont have any animators in our team, so I created a crack on his glass chest to make it more detailed and let the audience not focus on the heart inside,but leave the heart's red there to rich the colours.
The back part, also used two types of bump map.
Our lucky number on the leg,cracks on the armour are all made in photoshop