It was like two-three years ago where I found out that the black box is actually orange. I think they have their own reason to paint the box orange. Imagine an airplane crash occur. It lands onto a house where it kinda explodes. Having the box in orange makes the thing easier to spot when all the metals at the place are pitch black!
Some information on black box, it records data on cockpit conversation and the settings for the plane such as speed, altitude. So, when a crash occur, people can investigate using the information that has been taped in that black box. It rarely damaged. I wonder what kind of metal it is made of.