| US 7,338,718 B2 | ||
| Zinc hot dip galvanized steel plate excellent in press formability and method for production thereof | ||
| Shoichiro Taira, Tokyo (Japan); Masaki Tada, Tokyo (Japan); Yoshiharu Sugimoto, Tokyo (Japan); Masayasu Nagoshi, Tokyo (Japan); Takashi Kawano, Tokyo (Japan); Etsuo Hamada, Tokyo (Japan); Satoru Ando, Tokyo (Japan); Shinji Ootsuka, Tokyo (Japan); and Masaaki Yamashita, Tokyo (Japan) | ||
| Assigned to JFE Steel Corporation, Tokyo (Japan) | ||
| Appl. No. 10/521,474 PCT Filed Oct. 17, 2003, PCT No. PCT/JP03/13281 § 371(c)(1), (2), (4) Date Feb. 09, 2005, PCT Pub. No. WO2004/094683, PCT Pub. Date Nov. 04, 2004. |
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| Claims priority of application No. 2003-113938 (JP), filed on Apr. 18, 2003. | ||
| Prior Publication US 2005/0139291 A1, Jun. 30, 2005 | ||
| Int. Cl. B32B 15/04 (2006.01); C23C 2/06 (2006.01); C23C 2/26 (2006.01) | ||
| U.S. Cl. 428—633 [428/632; 428/659; 428/687] | 18 Claims |
| 1. A hot-dip galvanized steel sheet comprising:
a plating layer consisting essentially of a η phase; and
an oxide layer disposed on a surface of the plating layer, said oxide layer having an average thickness of 10 nm or more;
and
the oxide layer comprising a Zn-based oxide layer and an Al-based oxide layer, the Zn-based oxide layer having a Zn/Al atomic
concentration ratio of more than 1 and the Al-based oxide layer having a Zn/Al atomic concentration ratio of less than 1,
wherein the Zn-based oxide layer has microirregularities; and
the microirregularities have a mean spacing (S) determined based on a roughness curve of 1,000 nm or less and an average roughness
(Ra) of 100 nm or less.
|