Both 316 stainless steel and 316L stainless steel have good heat resistance, especially the heat resistance in oxidizing environments. This is mainly due to the chromium element in them, which can form a stable oxide film at high temperatures to protect the metal surface from high-temperature oxidation. Therefore, 316 stainless steel and 316L stainless steel are suitable for use under high temperature conditions, such as furnaces, heat exchangers, steam turbines, etc.
However, 316L stainless steel has better heat resistance, especially the heat resistance to carbide precipitation. This is because the low carbon content of 316L stainless steel makes it difficult to form carbides at high temperatures and precipitate at the grain boundaries, thereby avoiding the occurrence of carbide precipitation. Carbide precipitation is an important factor affecting the heat resistance of austenitic stainless steel, which can lead to embrittlement and strength reduction of metal materials. Therefore, under high temperature conditions, it is best not to use 316 stainless steel continuously, but to choose 316L stainless steel.
According to the international standard ISO 15156-3:2015 "Oil and natural gas industry - Resistance of materials to environmental cracking - Part 3: Crack-sensitive nickel alloys and other special materials", 316 stainless steel is suitable for intermittent use below 1600°C and It has good oxidation resistance in continuous use below 1700℃, while 316L stainless steel has better carbide precipitation resistance than 316 stainless steel and can be used continuously in the range of 800-1575℃.
