Olive Drab Phosphate Coating: Practical, Proven Guidance

Summary for olive drab phosphate coating Discussion

olive drab phosphate or chromate conversion coating is discussed as a finish choice for steel parts that need a very dark olive drab green appearance. In the question, Jeff Kubosh asks for the materials and process to phosphate coat or chromate conversion coat steel parts. The answer explains that steel cannot be chromated directly; chromate conversion coating is applied to zinc-plated parts, not bare steel. For steel, phosphating is the more promising and economical route. The reply also notes that phosphate finishes need to be kept oiled for corrosion resistance, and points to the possibility of an olive drab post-dip on the phosphate, as discussed in another thread, or using colored oils, which another thread says are available. The overall guidance is that a phosphate finish plus oil may be the practical way to approach the desired dark olive drab look on steel.