Invention Grant
- Patent Title: High-strength cold-rolled steel sheet excellent in bending workability
- Patent Title (中): 弯曲加工性优异的高强度冷轧钢板
-
Application No.: US12708109Application Date: 2010-02-18
-
Publication No.: US08460800B2Publication Date: 2013-06-11
- Inventor: Tetsuji Hoshika , Sae Mizuta , Yuichi Futamura , Masaaki Miura , Yukihiro Utsumi , Hiroaki Matsumoto , Hiroki Ohta
- Applicant: Tetsuji Hoshika , Sae Mizuta , Yuichi Futamura , Masaaki Miura , Yukihiro Utsumi , Hiroaki Matsumoto , Hiroki Ohta
- Applicant Address: JP Kobe-shi
- Assignee: Kobe Steel, Ltd.
- Current Assignee: Kobe Steel, Ltd.
- Current Assignee Address: JP Kobe-shi
- Agency: Oblon, Spivak, McClelland, Maier & Neustadt, L.L.P.
- Priority: JP2009-087407 20090331; JP2009-087408 20090331
- Main IPC: B32B15/01
- IPC: B32B15/01 ; B32B15/04 ; B32B15/18

Abstract:
Disclosed is a cold-rolled steel sheet having a specific steel composition and having a composite steel structure including a ferrite structure and a martensite-containing second phase. In a surface region of the steel sheet from the surface to a depth one-tenth the gage, the number density of n-ary groups of inclusions determined by specific n-th determinations is 120 or less per 100 cm2 of a rolling plane, in which the distance in steel sheet rolling direction between outermost surfaces of two outermost particles of the group of inclusions is 80 μm or more. Also disclosed is a cold-rolled steel sheet having a specific steel composition and having a steel structure of a martensite single-phase structure. In the surface region, the number density of groups of inclusions, in which the distance between the outermost surfaces is 100 μm or more, is 120 or less per 100 cm2 of a rolling plane.
Public/Granted literature
- US20100247957A1 HIGH-STRENGTH COLD-ROLLED STEEL SHEET EXCELLENT IN BENDING WORKABILITY Public/Granted day:2010-09-30
Information query