Steels react differently to chrome-plating, depending on their carbon content. Low carbon 'mild' steels chrome nicely with little drama, but high carbon content steels such as are used in springs, anti-sway bars and grade 5 or grade 8 bolts soak up hydrogen gas during the chroming process. The hydrogen penetrated the steel grain boundaries & makes the steel brittle & fracture-prone These types of steel are nearly always used under heavy loads. The whole process is called "hydrogen embrittlement" and has been known to chrome plates since WW2. The only work-around is to bake the plated parts for a couple of hours at high temperature to drive the hydrogen bubbles out of the parts. Of course, baking at TOO high a temperature causes the chrome to yellow or turn tan.....Most platers will bake the parts out, if you ask, for an additional fee. This is usually not something you can do in Mom's oven with any degree of control, and as mentioned before, the parts involved are often highly stressed. So if they let go at speed, you'll likely have far more excitement in your life than is really desirable. Cadmium plating also causes this problem, but to a lesser degree.
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