VCFERROUS HT Hot Blackening Chemical - Hot blackening, also known as hot black oxide coating, is a chemical conversion process that imparts a durable black finish to ferrous metals like steel and iron. This method enhances corrosion resistance, reduces light reflection, and improves the aesthetic appeal of metal components.​ * What Is VCFERROUS HT & How It Works - VCFERROUS HT is a hot blackening chemical used to apply a black oxide coating to ferrous metals (mainly mild steel, carbon steel, and some low-alloy steels). This is part of the hot blackening (hot oxide) process, which creates a durable, corrosion-resistant black finish without significantly changing the dimensions of the metal part. #VCFERROUS HT Hot Blackening Chemical Manufacturer.