MANUFACTURING METHOD OF HOT-DIP GALVANIZED STEEL SHEET

• Main Authors: HOSHINO KATSUYA, FURUYA SHINICHI
• Format: Patent
• Language: English; Japanese
• Published: 01.10.2020
• Subjects: CHEMICAL SURFACE TREATMENT; CHEMISTRY; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY IONIMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; DIFFUSION TREATMENT OF METALLIC MATERIAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; METALLURGY; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THESURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION

To provide a manufacturing method of a hot-dip galvanized steel sheet having excellent press formability, without requiring industrially special environmental measures or facility specifications.SOLUTION: A hot-dip galvanized steel sheet, to which temper rolling is applied, is brought into contact, as long as one second or more, with zinc sulfate aqueous solution having pH of 4.2-7.0, and containing one or more kinds of fluorine compounds selected from between NaHF2, KHF2, HF, NaF, KF as much as 0.10 g/L or more and 5.0 g/L or less in total, and then washed with water.SELECTED DRAWING: Figure 2 【課題】工業的に特段の環境対策や設備仕様を必要としないで、優れたプレス成形性を有する溶融亜鉛系めっき鋼板を製造する方法を提供する【解決手段】溶融亜鉛系めっき鋼板を、調質圧延を施した後、ＮａＨＦ２、ＫＨＦ２、ＨＦ、ＮａＦ、ＫＦの中から選ばれる１種以上のフッ素化合物を、合計量で０．１０ｇ／Ｌ以上５．０ｇ／Ｌ以下含有するｐＨ４．２〜７．０の硫酸亜鉛水溶液に１秒以上接触させ、その後水洗を行う【選択図】図２