Generally refers to chromed chrome plating, chrome, there are two, one is decorative chromium, one is hard chrome. Hard chrome plating is a better method of increasing a surface-hardness, but many of its advantages and disadvantages, so under no circumstances use a lot.
advantage:
First, the surface finish.
Second, it will not rust, will not be a little rust.
Third, the plating process Zhongyuan part distortion.
Fourth, if the size of the metal parts are not in place, you can add Jisi chromium to size (which is an advantage, but also a disadvantage, so chrome-plated parts should be put up margin).
Fifth, the surface is beautiful.