A newly developed snow vehicle (SM100S) for Antarctica III. Low temperature toughness of the welded joints of the structural steel

Abstract

For the purpose of developing a new snow vehicle car (common use at temperature about -50℃) for the deep ice coring project at Dome Fuji, East Antarctica, the low temperature toughness of the welded joints of structural steel was investigated. It is empirically well known that in case of vehicles employed in a cold air temperature of about -50℃, the low temperature brittle fracture of the structural members does not take place, if one uses the semi-killed or the killed steel, for which 50% FATT'S (fracture appearance transition temperature) of the Charpy impact test is about -50℃ and Charpy impact values at -50℃ are 20–29J/(cm)^2. In the present paper, the Charpy impact test has been performed for both single pass SMAW and (CO)_2 arc welded joints of JIS steels of SS400,SL2N255,STPL380,and STPL450. The test results show that the JIS steels of SL2N255 and STPL450 can be used for the new vehicle, considering their toughness.