Now the two most commonly used stainless steel 304,316 (or corresponding to the German / European standard 1.4308,1.4408), 316 and 304 in the chemical composition of the most important distinction is the 316 with Mo, and generally accepted, the corrosion resistance of 316 betterthan 304, more resistant to corrosion in high temperature environments. Therefore, under high temperature environment, the engineer will generally choose to 316 parts of the material. But things are no absolutes, concentrated sulfuric acid environment, no matter how high the temperature also do not use 316! Otherwise, this may make a big. Who studied mechanical engineering and learned thread, remember that in order to prevent thread killed in a high-temperature case, the need to smear a dark solid lubricants: molybdenum disulfide (MoS2), derived from it 2:00 the conclusion is not: [1] Moisturizer is indeed a high temperature material (know the gold what crucible melting? molybdenum crucible!). [2]: molybdenum easily and High sulfur ion reaction to generate the sulfide. So there is no any kind of stainless steel is invincible super corrosion resistance. After all, stainless steel is an impurity (although these impurities than steel is more resistant to corrosion ^ ^) more steel, steel and other substances reaction.