Kim, Myung-Yeon Chu, Dong-Ju Lee, Young-Su Jung, Woo-Sang Lee, Joonho Lee, Young-Kook Shim, Jae-Hyeok 2024-01-19T17:03:33Z 2024-01-19T17:03:33Z 2021-09-05 2020-07-03 0921-5093 https://pubs.kist.re.kr/handle/201004/118403 The effect of long-term aging at 550 degrees C on the hardness variation and precipitation evolution of a 1.25Cr-0.5Mo steel with ferrite/pearlite structure was investigated. Also, creep-rupture test of the steel was conducted at 550 degrees C. The hardness value generally decreased with increasing aging time due to the spheroidization of cementite (M3C). Interestingly, the hardness value was almost maintained at the aging time ranging from 1,000 to 5,000 h most likely due to the formation of fine needle-like M2C precipitates in ferrite regions. After 5,000 h of aging, the hardness value again decreased with the decrease in the amount of M3C. X-ray diffraction and transmission electron microscopy indicate that the amounts of M2C and M7C3 increases instead of M3C and some of M7C3 precipitates nucleated at M3C particles, growing at the expense of M 3 C around ferrite/pearlite interfaces. On the whole, the simulated precipitation kinetics of the steel using the MatCalc software well described the precipitation sequence. The creep-rupture strength of the steel drastically decreased especially after 1,600 h of rupture time, although it generally decreased with increasing rupture time. The accelerated dissolution of M3C under creep stress/strain was responsible for the drastic decrease in creep-rupture strength. English ELSEVIER SCIENCE SA SUPERIMPOSED CREEP STRESS FIRED POWER-PLANT M2C CARBIDES BEHAVIOR MICROSTRUCTURE RESISTANCE STRENGTH KINETICS Mechanical property change and precipitate evolution during long-term aging of 1.25Cr-0.5Mo steel Article 10.1016/j.msea.2020.139663 1 MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING, v.789 MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING 789 scie scopus 000543423100020 2-s2.0-85086500908 Nanoscience & Nanotechnology Materials Science, Multidisciplinary Metallurgy & Metallurgical Engineering Science & Technology - Other Topics Materials Science Metallurgy & Metallurgical Engineering Article SUPERIMPOSED CREEP STRESS FIRED POWER-PLANT M2C CARBIDES BEHAVIOR MICROSTRUCTURE RESISTANCE STRENGTH KINETICS Cr-Mo steel Aging Creep Precipitate evolution Kinetic simulation