Hot-dip plating method

Patent metadata

Field	Value
Publication number	US-11566315-B2
Application number	US-201917288519-A
Country	US
Kind code	B2
Filing date	Nov 6, 2019
Priority date	Nov 6, 2018
Publication date	Jan 31, 2023
Grant date	Jan 31, 2023

Abstract

Provided is a hot-dip plating method that achieves good plating wettability between a metal material and a hot-dip plating bath and that makes it possible to reduce the amount of consumed energy as compared to conventional techniques. In a plating step included in the hot-dip plating method, vibration is applied to a hot-dip plating bath such that the ratio of the average sound pressure level (excluding noise) over ranges each lying between sound pressure peaks at harmonic frequencies of a fundamental frequency to the average sound pressure level (excluding noise) over the measured frequency range in an acoustic spectrum is greater than 0.2.

First claim

The invention claimed is:

1. A hot-dip plating method comprising a plating step,
the plating step comprising causing a metal material to advance into a plating bath which is a molten metal and allowing the metal material to be coated with the molten metal while applying vibration to the plating bath while the metal material is in contact with the molten metal, wherein
a frequency of the vibration applied to the plating bath is a fundamental frequency,
in the plating step, the vibration is applied, on the basis of a result obtained by measuring an acoustic spectrum in the plating bath with use of an acoustic measuring instrument dipped in the plating bath, such that the acoustic spectrum measured in the plating bath satisfies a relationship represented by the following expression (1):
( IB−NB )/( IA−NA )>0.2,

where
IA is an average sound pressure level over an entire measured frequency range,
IB is an average sound pressure level over specific frequency ranges including (i) a range lying between a sound pressure peak at the fundamental frequency and a sound pressure peak at a second-harmonic frequency and (ii) each range lying between sound pressure peaks at adjacent ones of a plurality of harmonic frequencies,
NA is an average sound pressure level over the entire measured frequency range when the vibration is not applied, and
NB is an average sound pressure level over the specific frequency ranges defined for the IB when the vibration is not applied, and
a power of the vibration is not less than 0.5 W and not more than 30 W.

2. The hot-dip plating method as set forth in claim 1 , comprising subjecting the metal material to a degreasing treatment or a pickling treatment as one or more pre-treatments prior to the plating step.

3. The hot-dip plating method as set forth in claim 1 , wherein, in the plating step,
a distance between (i) a location where the acoustic spectrum is measured with use of the acoustic measuring instrument in the plating bath and (ii) a surface of the metal material is not more than 10 mm.

4. A hot-dip plating method comprising a plating step,
the plating step comprising causing a metal material to advance into a plating bath which is a molten metal and allowing the metal material to be coated with the molten metal while applying vibration to the plating bath while the metal material is in contact with the molten metal, wherein
a frequency of the vibration applied to the plating bath is a fundamental frequency,
in the plating step, the vibration is applied, on the basis of a result obtained by measuring an acoustic spectrum in the plating bath with use of an acoustic measuring instrument dipped in the plating bath, such that the acoustic spectrum measured in the plating bath satisfies a relationship represented by the following expression (1):
( IB−NB )/( IA−NA )>0.2,

where
IA is an average sound pressure level over an entire measured frequency range,
IB is an average sound pressure level over specific frequency ranges including (i) a range lying between a sound pressure peak at the fundamental frequency and a sound pressure peak at a second-harmonic frequency and (ii) each range lying between sound pressure peaks at adjacent ones of a plurality of harmonic frequencies,
NA is an average sound pressure level over the entire measured frequency range when the vibration is not applied, and
NB is an average sound pressure level over the specific frequency ranges defined for the IB when the vibration is not applied, and
the entire measured frequency range is 10 kHz to 90 kHz.

5. The hot-dip plating method as set forth in claim 4 , comprising subjecting the metal material to a degreasing treatment or a pickling treatment as one or more pre-treatments prior to the plating step.

6. The hot-dip plating method as set forth in claim 4 , wherein, in the plating step,
a distance between (i) a location where the acoustic spectrum is measured with use of the acoustic measuring instrument in the plating bath and (ii) a surface of the metal material is not more than 10 mm.

Assignees

• Nippon Steel Corp

Inventors

• Miono Tadaaki
• Kamoshida Shinichi
• Koga Shinichi
• Hattori Yasunori

Classifications

• C23C2/32 Primary

  using vibratory energy applied to the bath or substrate (C23C2/14 takes precedence) · CPC title

• C23C2/02

  Pretreatment of the material to be coated, e.g. for coating on selected surface areas (C23C2/30 takes precedence) · CPC title

• C23C28/00

  Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D · CPC title

• C23C28/3225

  with at least one zinc-based layer · CPC title

• C23C2/06 Primary

  Zinc or cadmium or alloys based thereon · CPC title