TY - GEN
T1 - Improvement in punching properties of high tensile strength steel sheet by heat-treatments for reduction of center segregation
AU - Sakumoto, Kota
AU - Yamazaki, Kazuhiko
AU - Kobayashi, Takashi
AU - Suzuki, Shinsuke
N1 - Publisher Copyright:
© (2014) Trans Tech Publications, Switzerland.
PY - 2014
Y1 - 2014
N2 - We investigated punching properties (crack in punched surface and hole expansion ratio) of high tensile strength steel sheets with and without center segregation. High strength steel sheets were heat-treated to reduce center segregation. Tensile strength, shear surface ratio, depth of rollover and burr height were measured on heat-treated steel sheets to confirm the effect of heat-treatment on strength. The EPMA analysis showed that the center segregation of Mn was reduced by the diffusion during heat-treatment. Crack-formation frequency and hole expansion ratio were also measured. As a result, the center segregation of Mn in high tensile strength steel sheets decreased by the heat-treatment (600 deg;C for 100 h) with maintaining the tensile strength, the depth of rollover and the burr height. The crack-formation frequency of the steel sheets decreased through heat-treatments.
AB - We investigated punching properties (crack in punched surface and hole expansion ratio) of high tensile strength steel sheets with and without center segregation. High strength steel sheets were heat-treated to reduce center segregation. Tensile strength, shear surface ratio, depth of rollover and burr height were measured on heat-treated steel sheets to confirm the effect of heat-treatment on strength. The EPMA analysis showed that the center segregation of Mn was reduced by the diffusion during heat-treatment. Crack-formation frequency and hole expansion ratio were also measured. As a result, the center segregation of Mn in high tensile strength steel sheets decreased by the heat-treatment (600 deg;C for 100 h) with maintaining the tensile strength, the depth of rollover and the burr height. The crack-formation frequency of the steel sheets decreased through heat-treatments.
KW - Center segregation
KW - High tensile steel sheet
KW - Hole expansion ratio
KW - Punching
UR - http://www.scopus.com/inward/record.url?scp=84923084177&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84923084177&partnerID=8YFLogxK
U2 - 10.4028/www.scientific.net/KEM.622-623.1075
DO - 10.4028/www.scientific.net/KEM.622-623.1075
M3 - Conference contribution
AN - SCOPUS:84923084177
T3 - Key Engineering Materials
SP - 1075
EP - 1080
BT - Metal Forming 2014
A2 - Micari, Fabrizio
A2 - Fratini, Livan
PB - Trans Tech Publications Ltd
T2 - 15th International Conference on Metal Forming 2014
Y2 - 21 September 2014 through 24 September 2014
ER -