TY - GEN
T1 - Effect of precipitation on cryogenic toughness in N-containing austenitic stainless steels
AU - Saucedo-Muñoz, M. L.
AU - Hashida, T.
AU - Watanabe, Y.
AU - Shoji, T.
AU - Lopez-Hirata, V. M.
PY - 2007
Y1 - 2007
N2 - Three types of austenitic stainless steels JK2, JJ1 and JN1 were isothermally aged at temperatures from 600 to 900°C for 10 to 1000 minutes in order to study the microstructural evolution and its effect on the fracture toughness at cryogenic temperatures. The Charpy V-Notch fracture energy at 77 K showed a significant decrease with aging time in JJ1 and JN1 steels because of their higher contents of C and N. In contrast, the fracture energy corresponding to the aged JK2 steel decreased gradually with aging time. The abundant intergranular precipitation of carbides and nitrides seems to be the responsible for the fracture toughness deterioration in the aged JJ1 and JN1 steels. On the other hand, the intergranular precipitation of carbides was less abundant in the aged JK2 steel. The scanning electron microscope fractographs of the CVN test specimens corresponding to the aged JJ1 and JN1 steels showed mainly an intergranular brittle fracture and its fraction increased with aging time and temperature. In general, the presence of a more abundant intergranular precipitation resulted in a more rapid decrease in toughness with aging time.
AB - Three types of austenitic stainless steels JK2, JJ1 and JN1 were isothermally aged at temperatures from 600 to 900°C for 10 to 1000 minutes in order to study the microstructural evolution and its effect on the fracture toughness at cryogenic temperatures. The Charpy V-Notch fracture energy at 77 K showed a significant decrease with aging time in JJ1 and JN1 steels because of their higher contents of C and N. In contrast, the fracture energy corresponding to the aged JK2 steel decreased gradually with aging time. The abundant intergranular precipitation of carbides and nitrides seems to be the responsible for the fracture toughness deterioration in the aged JJ1 and JN1 steels. On the other hand, the intergranular precipitation of carbides was less abundant in the aged JK2 steel. The scanning electron microscope fractographs of the CVN test specimens corresponding to the aged JJ1 and JN1 steels showed mainly an intergranular brittle fracture and its fraction increased with aging time and temperature. In general, the presence of a more abundant intergranular precipitation resulted in a more rapid decrease in toughness with aging time.
KW - Austenitic stainless steels
KW - Cryogenic toughness
KW - Precipitation
UR - http://www.scopus.com/inward/record.url?scp=38349002821&partnerID=8YFLogxK
U2 - 10.4028/0-87849-428-6.4914
DO - 10.4028/0-87849-428-6.4914
M3 - Contribución a la conferencia
SN - 0878494286
SN - 9780878494286
T3 - Materials Science Forum
SP - 4914
EP - 4919
BT - Supplement to THERMEC 2006, 5th International Conference on Processing and Manufacturing of Advanced Materials, THERMEC 2006
PB - Trans Tech Publications Ltd
T2 - 5th International Conference on Processing and Manufacturing of Advanced Materials - THERMEC'2006
Y2 - 4 July 2006 through 8 July 2006
ER -