Explanation

It is generally specified that the yield strength of insulation at 600 ° C for a certain period of time (1-3h) is greater than 2/3 of the room temperature yield strength. It is used for engineering structural steel of steel structure buildings or high-rise large buildings with fire and collapse resistance under certain conditions. Adding appropriate alloy elements such as niobium, molybdenum, etc. and adopting controlled rolling process, precipitation strengthening of carbonitride and solution strengthening of alloy elements can significantly improve the high-temperature yield strength of steel product and thus obtain fire-resistant steel.

Classification