US4383006A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hot-dip galvanized steel sheet with zero-spangle having excellent age-flaking resistance, and hot-dip galvanizing process and composition of molten zinc bath therefor
Assignee: Nippon Steel Corp
•
Filing: 1981-07-08
•
Granted: 1983-05-10
•
Expires: 2001-07-08
Abstract
Abstract Hot-dip galvanized steel sheet, wherein said coating layer is characterized by being highly resistant to flaking either in a high-temperature humid atmosphere or in long-term indoor aging. The coating comprises 0.1 to less than 0.2 wt % Al, 0.1-0.5 wt % Sb, the remainder being Zn and unavoidable impurities, the total of the unavoidable impurities other than Fe, namely Pb, Cd and Sn being less than 0.02 wt %, the ratio of Sb/Pb being 10-250, and the Al present in the coating layer being in the form of an Al-Sb eutectic.
Inventors
- 👤 Yoshio Shindo
- 👤 Teppei Tamura
- 👤 Motoo Kabeya
- 👤 Mitsumasa Nagahisa
- 👤 Hidejirou Asano
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 22:55
CPC Classifications
C; C23; C23C; C23C2/00; C23C2/04; C23C2/06; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12493; Y10T428/12771; Y10T428/12785; Y10T428/12792; Y10T428/12799
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
96 words
An improved zero-spangle galvanized steel sheet having excellent resistance to age-flaking of its galvanized coating comprising a steel sheet provided at least on one side thereof with a hot-dip galvanized coating of a novel composition consisting of 0.1 to less than 0.2 weight % Al, 0.1-0.5 weight % Sb, unavoidable impurities including Pb, Cd and Sn but not including Fe in a total amount of less than 0.02 weight % and the remainder Zn, the ratio of Sb/Pb in said coating being 10-250, and the Al existing in said coating being present as an Al-Sb eutectic.
Claim 2
Dependent Claim
96 words
An improved zero-spangle galvanized steel sheet having excellent resistance to age-flaking of its galvanized coating comprising a steel sheet provided at least on one side thereof with a hot-dip galvanized coating of a novel composition consisting of 0.1 to less than 0.2 weight % Al, 0.1-0.5 weight % Sb, unavoidable impurities including Pb, Cd and Sn but not including Fe in a total amount of less than 0.02 weight % and the remainder Zn, the ratio of Sb/Pb in said coating being 10-250, and the Al existing in said coating being present as an Al-Sb eutectic.
Claim 3
Dependent Claim
52 words
An improved hot-dip galvanizing bath comprising 0.1 to less than 0.2 weight % Al, 0.1-0.5 weight % Sb, unavoidable impurities including Pb, Cd and Sn but not including Fe in a total amount of less than 0.2 weight % and the remainder Zn, the ratio of Sb/Pb in said bath being 10-250.
Claim 4
Dependent Claim
52 words
An improved hot-dip galvanizing bath comprising 0.1 to less than 0.2 weight % Al, 0.1-0.5 weight % Sb, unavoidable impurities including Pb, Cd and Sn but not including Fe in a total amount of less than 0.2 weight % and the remainder Zn, the ratio of Sb/Pb in said bath being 10-250.
Claim 5
Dependent Claim
16 words
An improved hot-dip galvanizing bath as claimed in claim 2 which contains 0.1-0.15 weight % Al.
Claim 6
Dependent Claim
16 words
An improved hot-dip galvanizing bath as claimed in claim 2 which contains 0.15-0.3 weight % Sb.
Claim 7
Dependent Claim
33 words
An improved hot-dip galvanizing bath as claimed in claim 2 in which the total amount of unavoidable impurities including Pb, Cd and Sn but not including Fe is less than 0.01 weight %.
Claim 8
Dependent Claim
18 words
An improved hot-dip galvanizing bath as claimed in claim 2 in which the ratio of Sb/Pb is 40-200.
Claim 9
Independent Claim
92 words
A method for the manufacture of a zero-spangle hot-dip galvanized steel sheet having excellent resistance to an age-flaking of said galvanized coating which comprises the steps of hot-dipping a steel sheet in a hot-dip galvanizing bath consisting of 0.1 to less than 0.2 weight % Al, 0.1-0.5 weight % Sb, unavoidable impurities including Pb, Cd and Sn but not including Fe in a total amount of less than 0.02 weight %, the ratio of Sb/Pb being 10-250, and the remainder Zn, and subsequently processing said hot-dipped steel sheet by a zero-spangled treatment.
Claim 10
Independent Claim
92 words
A method for the manufacture of a zero-spangle hot-dip galvanized steel sheet having excellent resistance to an age-flaking of said galvanized coating which comprises the steps of hot-dipping a steel sheet in a hot-dip galvanizing bath consisting of 0.1 to less than 0.2 weight % Al, 0.1-0.5 weight % Sb, unavoidable impurities including Pb, Cd and Sn but not including Fe in a total amount of less than 0.02 weight %, the ratio of Sb/Pb being 10-250, and the remainder Zn, and subsequently processing said hot-dipped steel sheet by a zero-spangled treatment.
Claim 11
Dependent Claim
28 words
A method for the manufacture of a zero-spangle hot-dip galvanized steel sheet as claimed in claim 7 in which said hot-dip galvanizing bath contains 0.1-0.15 weight % Al.
Claim 12
Dependent Claim
28 words
A method for the manufacture of a zero-spangle hot-dip galvanized steel sheet as claimed in claim 7 in which said hot-dip galvanizing bath contains 0.15-0.3 weight % Sb.
Claim 13
Dependent Claim
45 words
A method for the manufacture of a zero-spangle hot-dip galvanized steel sheet as claimed in claim 7 in which said hot-dip galvanizing bath contains unavoidable impurities including Pb, Cd and Sn but not including Fe in a total amount of less than 0.01 weight %.
Claim 14
Dependent Claim
29 words
A method for the manufacture of a zero-spangle hot-dip galvanized steel sheet as claimed in claim 7 in which the ratio of Sb/Pb in said galvanized bath is 40-200.
Claim 15
Dependent Claim
60 words
A method for the manufacture of a zero-spangle hot-dip galvanized steel sheet having excellent resistance to age-flaking of said galvanized coating as claimed in claim 7 in which, in the course of cooling said molten galvanized coating, said coating is subjected to a zero-spangle quenching treatment while the cooling speed of said steel is maintained at 100°-300° C. per second.
Claim 16
Dependent Claim
11 words
The zero-spangle galvanized sheet produced by the method of claim 7.
References Cited (Backward Citations)
US4056657A
Cited
US4056366A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-05-09 | 1986-11-08 | 1987-05-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-05-09 | 1990-11-08 | 1991-05-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-05-09 | 1994-11-08 | 1995-05-10 | $7700.00 | Window Closed / Lapsed |