发明申请
- 专利标题: STEEL MATERIAL FOR AUTOMOBILE CHASSIS PARTS SUPERIOR IN FATIGUE CHARACTERISTICS AND METHOD OF PRODUCTION OF AUTOMOBILE CHASSIS PARTS USING THE SAME
- 专利标题(中): 用于汽车零部件的钢材料疲劳特性及其生产汽车零部件的方法
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申请号: US12310033申请日: 2007-08-08
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公开(公告)号: US20090277542A1公开(公告)日: 2009-11-12
- 发明人: Hideyuki Nakamura , Isao Anai , Yasushi Yamamoto , Takaaki Fukushi , Izuru Yamamoto , Masaaki Kondo , Satoru Shimazu
- 申请人: Hideyuki Nakamura , Isao Anai , Yasushi Yamamoto , Takaaki Fukushi , Izuru Yamamoto , Masaaki Kondo , Satoru Shimazu
- 优先权: JP2006-219737 20060811; JP2007-197348 20070730
- 国际申请: PCT/JP2007/065893 WO 20070808
- 主分类号: C21D6/00
- IPC分类号: C21D6/00 ; C22C38/12 ; C22C38/00 ; C22C38/04 ; C22C38/08 ; C22C38/16 ; C22C38/22 ; C22C38/26
摘要:
The present invention provides a steel material for automobile chassis parts which has high fatigue characteristics, does not require much cost for heat treatment, and further is superior in shapeability and a method of production of automobile chassis parts using this steel material, that is, one being a steel material to which Nb and Mo have been compositely added and having a difference 50 to 150 points between a Vicker's hardness of the center of plate thickness and a maximum value of Vicker's hardness within 0.5 mm from the surface after bending by a bending R of the plate outer surface of 2 to 5 times the plate thickness. The surface is high in hardness and the center part is low in hardness, so the fatigue characteristics and shapeability are superior. Note that if annealing under conditions giving a tempering parameter λ defined by λ=T(20+log(t)) of 14000 to 19000 (where T is the absolute temperature, t is the time (h), and the temperature rise is 660° C.), it is possible to relieve the internal stress and further improve the fatigue characteristics.