Does the temperature affect the quality of the steel plate

(1) When the temperature rises, the general tendency of the strength and elastic modulus of the steel plate is to decrease, but it does not change much when the temperature is below 150℃. When the temperature is 250℃, the tensile strength of the steel plate is greatly improved, but the plasticity and toughness become worse. At this time, the failure is brittle failure, called "blue brittleness". When the temperature exceeds 300℃, its strength and elastic modulus begin to decrease significantly, while plasticity begins to increase significantly, and the steel plate creeps. When it reaches 600℃, the strength of the steel plate is almost zero.

(2) When the temperature drops to negative temperature, although the strength of the steel plate increases, the plasticity and toughness decrease, the brittleness increases, and the brittle transition temperature appears. Taking the toughness index as an example, the steel plate temperature corresponding to the reversal point is the brittle transition temperature. When selecting steel plates, the ambient temperature of the structure should be higher than the lower limit of the brittle transition temperature, and the impact toughness should be sufficient at the ambient temperature.