Development and application on non-quenched and tempered steel for high strength fasteners
WANG Li-jun1,2,RUAN Shi-peng1,2,WANG Ning-tao1,2,ZHAI Jin-po1,2, ZHANG Su-ping1,2,WANG Jing1,2
(1. Technology Center, Xingtai Iron and Steel Co., Ltd., Xingtai 054027, Hebei, China 2. Hebei Engineering Research Center for Wire Rod, Xingtai 054027, Hebei, China)
Abstract:In order to develop energy-saving non quenched and tempered cold heading steel with high strength,high toughness and good processability,non-quenched and tempered steel for high strength fasteners was produced by “BOF-LF-CC-controlling rolling and cooling” process. The microstructure and properties,drawing process,aging process of test steel were studied. The results showed that the steel was fine ferrite and pearlite,the tensile strength and elongation ratio of the steel were respectively 739 MPa and 22.2%. The tensile strength could meet the demand of 9.8 and 10.9 stage bolt when drawing reductions respectively at the range of 15%-25% and 30%-40%. As the aging temperature increased, the tensile strength and hardness initially increased and then decreased after 150-450 ℃ aging. The tensile strength and hardness reaches a maximum value. The tensile strength and hardness increased with aging time increased after 0-2 h at 250 ℃. When the drawing reduction is 40%,the steel can bear the compression of 24.6% height ratio of front and back without cracking.
王利军,阮士朋,王宁涛,翟进坡,张素萍,王 晶,. 高强度螺栓用非调质钢的研制与应用[J]. , 2018, 53(11): 102-106.
WANG Li-jun,,RUAN Shi-peng,,WANG Ning-tao,,ZHAI Jin-po,, ZHANG Su-ping,,WANG Jing,. Development and application on non-quenched and tempered steel for high strength fasteners. Iron and Steel, 2018, 53(11): 102-106.