STEEL STRUCTURE FOR HYDROGEN WHICH EXHIBITS EXCELLENT HYDROGEN EMBRITTLEMENT RESISTANCE PROPERTIES IN HIGH PRESSURE HYDROGEN GAS AND METHOD FOR PRODUCING SAME

摘要

ABSTRACT STEEL STRUCTURE FOR HYDROGEN GAS WITH EXCELLENT HYDROGEN EMBRITTLEMENT RESISTANCE IN HIGH PRESSURE HYDROGEN GAS AND METHOD OF PRODUCING THE SAME By having a steel composition containing, by mass%, C: 0.02 % to 0.50%, Si: 0.05 % to 0.50 %: Mn: 0.5 % to 2.0 %, P: 0.05 % or less, S: 0.01 % or less, Al: 0.01 % to 0.10 %, N: 0.0005 % to 0.008 %, O: 0.01 % or less, and V: 0.05 % to 0.30 % and Mo: 0.05 % to 1.13 % where a ratio of number of V atoms to number of Mo atoms is in a range of 0.6 to 2.0, the balance being Fe and inevitable impurities, and controlling the average particle size of fine complex carbides of V and Mo in a range of 1 nm to 20 nm, a steel structure for hydrogen gas such as a hydrogen storage vessel or a hydrogen line pipe that has excellent hydrogen embrittlement resistance in high pressure hydrogen environment can be obtained.