JP2011153349A5

JP2011153349A5 -

Info

Publication number: JP2011153349A5
Application number: JP2010015663A
Authority: JP
Filing date: 2010-01-27
Publication date: 2012-03-08

Claims

母材である鋼板の表面に合金化溶融亜鉛めっき層を備える合金化溶融亜鉛めっき鋼板であって、前記表面に形成された、厚さが２０μｍ以下の脱炭層を有することを特徴とする合金化溶融亜鉛めっき鋼板。 An alloyed hot-dip galvanized steel sheet having an alloyed hot-dip galvanized layer on the surface of a steel sheet as a base material, characterized by having a decarburized layer having a thickness of 20 μm or less formed on the surface Hot dip galvanized steel sheet .

前記鋼板は、質量％で、Ｃ：０．０１〜０．２５％、Ｓｉ：０．３〜２．０％、Ｍｎ：０．０３０〜３．０％、Ｐ：０．０５０％以下、Ｓ：０．０１０％以下、Ｎ：０．００６０％以下、及び、ｓｏｌ．Ａｌ：０．５％以下、かつ、残部Ｆｅ及び不純物からなる化学組成を有するとともに、前記合金化溶融亜鉛めっき層は、質量％で、Ｆｅ：８．０〜１５％、及び、Ａｌ：０．１５〜０．５０％を含有する請求項１に記載された合金化溶融亜鉛めっき鋼板。 The said steel plate is the mass%, C: 0.01-0.25%, Si: 0.3-2.0%, Mn: 0.030-3.0%, P: 0.050% or less, S : 0.010% or less, N: 0.0060% or less, and sol. The alloyed hot-dip galvanized layer has a chemical composition consisting of Al: 0.5% or less and the balance Fe and impurities, and the alloyed hot-dip galvanized layer is Fe: 8.0-15% and Al: 0.00%. The alloyed hot-dip galvanized steel sheet according to claim 1, containing 15 to 0.50%.

前記化学組成は、質量％で、Ｔｉ：０．５０％以下、Ｎｂ：０．５０％以下、およびＢ：０．００５０％以下からなる群から選ばれた一種または二種以上を有する請求項２に記載された合金化溶融亜鉛めっき鋼板。 The chemical composition has one or more selected from the group consisting of Ti: 0.50% or less, Nb: 0.50% or less, and B: 0.0050% or less in mass%. The alloyed hot-dip galvanized steel sheet described in 1.

前記化学組成は、質量％で、Ｃｕ：１．０％以下、Ｎｉ：１．０％以下、Ｃｒ：１．０％以下およびＭｏ：１．０％以下からなる群から選ばれた一種または二種以上を有する請求項１から請求項３までのいずれか１項に記載された合金化溶融亜鉛めっき鋼板。 The chemical composition is one or two selected from the group consisting of Cu: 1.0% or less, Ni: 1.0% or less, Cr: 1.0% or less, and Mo: 1.0% or less in terms of mass%. The alloyed hot-dip galvanized steel sheet according to any one of claims 1 to 3, having at least seeds.

前記化学組成は、質量％で、Ｂｉ：０．００５％以下、及びＣａ：０．０１％以下の一種または二種を有する請求項１から請求項４までのいずれか１項に記載された合金化溶融亜鉛めっき鋼板。 The alloy according to any one of claims 1 to 4, wherein the chemical composition has one or two of Bi: 0.005% or less and Ca: 0.01% or less in mass%. Hot-dip galvanized steel sheet.

質量％で、Ｃ：０．０１〜０．２５％、Ｓｉ：０．３〜２．０％、Ｍｎ：０．０３０〜３．０％、Ｐ：０．０５０％以下、Ｓ：０．０１０％以下、Ｎ：０．００６０％以下、及び、ｓｏｌ．Ａｌ：０．５％以下を有する化学組成の鋼スラブに熱間圧延を行い、得られた熱延鋼板を６５０℃以下の巻き取り温度で巻き取る熱間圧延工程と、
該熱延鋼板を酸洗する酸洗工程と、
該酸洗工程で酸洗された熱延鋼板を圧下率５０％以上で冷間圧延する冷間圧延工程と、
該冷間圧延工程を経た冷延鋼板を連続溶融亜鉛めっきラインでの還元焼鈍炉で鋼板表面を還元する際に７００℃以上の温度域では水素濃度：１〜３０体積％および露点：−３０℃〜１０℃の窒素―水素雰囲気で焼鈍を行ってから、溶融亜鉛めっきを行い、ついで合金化処理を行う合金化溶融亜鉛めっき工程と
を備えることを特徴とする合金化溶融亜鉛めっき鋼板の製造方法。 In mass%, C: 0.01 to 0.25%, Si: 0.3 to 2.0%, Mn: 0.030 to 3.0%, P: 0.050% or less, S: 0.010 % Or less, N: 0.0060% or less, and sol. A hot rolling step of hot rolling a steel slab having a chemical composition having Al: 0.5% or less and winding the obtained hot rolled steel sheet at a winding temperature of 650 ° C. or less;
Pickling process for pickling the hot-rolled steel sheet;
A cold rolling process in which the hot-rolled steel sheet pickled in the pickling process is cold-rolled at a rolling reduction of 50% or more;
When the cold-rolled steel sheet that has undergone the cold rolling process is reduced on the steel sheet surface in a reduction annealing furnace in a continuous hot-dip galvanizing line, the hydrogen concentration is 1 to 30% by volume and the dew point is −30 ° C. in the temperature range of 700 ° C. or higher. An alloyed hot-dip galvanized steel sheet comprising: an alloying hot-dip galvanizing step in which hot-dip galvanizing is performed after annealing in a nitrogen-hydrogen atmosphere at -10 ° C, followed by alloying treatment. .