Carbon is an austenite stabilizer. Our Carbon steel pipe fitting Manufacturer are high performance, high strength pipe fittings that are made up of a combination of iron and carbon. There are also a number of other elements that are present in our carbon steel pipe fittings such as manganese, silicon & copper. The maximum percentage of these elements that are allowed is very low. Manganese is allowed a 1.65% maximum, while copper and silicon are allowed a 0.60% maximum. The Carbon present in our carbon steel pipe fittings considerably enhance the strength of the fittings (especially, in martensitic stainless steels), but as a result is may also have an adverse effect on corrosion resistance as it is likely for chromium carbides to form. Read more about Carbon Steel Pipe Fittings: http://instinox.com/pipe-fittings/carbon-steel-pipe-fittings/