JP2016176101A - Surface treated steel sheet for press molding, and press molded article - Google Patents
Surface treated steel sheet for press molding, and press molded article Download PDFInfo
- Publication number
- JP2016176101A JP2016176101A JP2015056364A JP2015056364A JP2016176101A JP 2016176101 A JP2016176101 A JP 2016176101A JP 2015056364 A JP2015056364 A JP 2015056364A JP 2015056364 A JP2015056364 A JP 2015056364A JP 2016176101 A JP2016176101 A JP 2016176101A
- Authority
- JP
- Japan
- Prior art keywords
- steel sheet
- zinc
- press
- plating layer
- layer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 86
- 239000010959 steel Substances 0.000 title claims abstract description 86
- 238000000465 moulding Methods 0.000 title abstract description 12
- 238000007747 plating Methods 0.000 claims description 76
- 239000011701 zinc Substances 0.000 claims description 62
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 claims description 61
- 229910052725 zinc Inorganic materials 0.000 claims description 61
- XOLBLPGZBRYERU-UHFFFAOYSA-N tin dioxide Chemical compound O=[Sn]=O XOLBLPGZBRYERU-UHFFFAOYSA-N 0.000 claims description 28
- 239000000126 substance Substances 0.000 claims description 17
- 239000000203 mixture Substances 0.000 claims description 11
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 10
- 229910001297 Zn alloy Inorganic materials 0.000 claims description 7
- 229910052804 chromium Inorganic materials 0.000 claims description 5
- 229910052802 copper Inorganic materials 0.000 claims description 5
- 229910052742 iron Inorganic materials 0.000 claims description 5
- 229910052759 nickel Inorganic materials 0.000 claims description 5
- 238000004544 sputter deposition Methods 0.000 claims description 5
- 239000012535 impurity Substances 0.000 claims description 3
- 239000011248 coating agent Substances 0.000 abstract description 49
- 238000000576 coating method Methods 0.000 abstract description 49
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 abstract description 26
- 239000011787 zinc oxide Substances 0.000 abstract description 13
- 238000000034 method Methods 0.000 description 31
- 239000000047 product Substances 0.000 description 26
- 238000010438 heat treatment Methods 0.000 description 25
- 230000000694 effects Effects 0.000 description 15
- 230000007797 corrosion Effects 0.000 description 13
- 238000005260 corrosion Methods 0.000 description 13
- 238000001816 cooling Methods 0.000 description 10
- 238000005275 alloying Methods 0.000 description 9
- 229910045601 alloy Inorganic materials 0.000 description 8
- 239000000956 alloy Substances 0.000 description 8
- 229910001335 Galvanized steel Inorganic materials 0.000 description 7
- 238000006243 chemical reaction Methods 0.000 description 7
- 238000004070 electrodeposition Methods 0.000 description 7
- 239000008397 galvanized steel Substances 0.000 description 7
- 238000004519 manufacturing process Methods 0.000 description 7
- 239000010960 cold rolled steel Substances 0.000 description 6
- 230000015572 biosynthetic process Effects 0.000 description 5
- 238000011156 evaluation Methods 0.000 description 5
- 238000007654 immersion Methods 0.000 description 5
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 5
- 239000000463 material Substances 0.000 description 5
- 230000009466 transformation Effects 0.000 description 5
- LRXTYHSAJDENHV-UHFFFAOYSA-H zinc phosphate Chemical compound [Zn+2].[Zn+2].[Zn+2].[O-]P([O-])([O-])=O.[O-]P([O-])([O-])=O LRXTYHSAJDENHV-UHFFFAOYSA-H 0.000 description 5
- 229910000165 zinc phosphate Inorganic materials 0.000 description 5
- 238000002474 experimental method Methods 0.000 description 4
- 238000005246 galvanizing Methods 0.000 description 4
- 230000003647 oxidation Effects 0.000 description 4
- 238000007254 oxidation reaction Methods 0.000 description 4
- 235000002639 sodium chloride Nutrition 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 3
- 239000012298 atmosphere Substances 0.000 description 3
- 229910001566 austenite Inorganic materials 0.000 description 3
- 229910001563 bainite Inorganic materials 0.000 description 3
- 238000005097 cold rolling Methods 0.000 description 3
- 238000007598 dipping method Methods 0.000 description 3
- 238000009713 electroplating Methods 0.000 description 3
- 239000012467 final product Substances 0.000 description 3
- 239000007789 gas Substances 0.000 description 3
- 238000005098 hot rolling Methods 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 229910052760 oxygen Inorganic materials 0.000 description 3
- 229910001562 pearlite Inorganic materials 0.000 description 3
- 238000012545 processing Methods 0.000 description 3
- 238000010791 quenching Methods 0.000 description 3
- 230000000717 retained effect Effects 0.000 description 3
- 229910000859 α-Fe Inorganic materials 0.000 description 3
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 2
- 229910007567 Zn-Ni Inorganic materials 0.000 description 2
- 229910007614 Zn—Ni Inorganic materials 0.000 description 2
- 238000000137 annealing Methods 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 238000005422 blasting Methods 0.000 description 2
- 238000007664 blowing Methods 0.000 description 2
- 125000002091 cationic group Chemical group 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 238000000151 deposition Methods 0.000 description 2
- 230000008021 deposition Effects 0.000 description 2
- 230000006866 deterioration Effects 0.000 description 2
- 229910052739 hydrogen Inorganic materials 0.000 description 2
- 238000009616 inductively coupled plasma Methods 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 230000000171 quenching effect Effects 0.000 description 2
- 150000003839 salts Chemical class 0.000 description 2
- 239000011780 sodium chloride Substances 0.000 description 2
- 239000006104 solid solution Substances 0.000 description 2
- 238000005482 strain hardening Methods 0.000 description 2
- 238000005728 strengthening Methods 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 1
- 229910018137 Al-Zn Inorganic materials 0.000 description 1
- 229910018573 Al—Zn Inorganic materials 0.000 description 1
- 229920000298 Cellophane Polymers 0.000 description 1
- 229910001128 Sn alloy Inorganic materials 0.000 description 1
- 229910020888 Sn-Cu Inorganic materials 0.000 description 1
- 229910019204 Sn—Cu Inorganic materials 0.000 description 1
- 238000002441 X-ray diffraction Methods 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 229910052788 barium Inorganic materials 0.000 description 1
- 229910052796 boron Inorganic materials 0.000 description 1
- 229910052791 calcium Inorganic materials 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000007739 conversion coating Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000002447 crystallographic data Methods 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 230000000593 degrading effect Effects 0.000 description 1
- 238000005238 degreasing Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005485 electric heating Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000001747 exhibiting effect Effects 0.000 description 1
- -1 for example Substances 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 229910052735 hafnium Inorganic materials 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxide Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 description 1
- 150000004679 hydroxides Chemical class 0.000 description 1
- 230000008595 infiltration Effects 0.000 description 1
- 238000001764 infiltration Methods 0.000 description 1
- 229910052749 magnesium Inorganic materials 0.000 description 1
- 229910052748 manganese Inorganic materials 0.000 description 1
- 229910000734 martensite Inorganic materials 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229910052750 molybdenum Inorganic materials 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 239000012299 nitrogen atmosphere Substances 0.000 description 1
- 239000003973 paint Substances 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 229910052761 rare earth metal Inorganic materials 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 238000002791 soaking Methods 0.000 description 1
- 238000004611 spectroscopical analysis Methods 0.000 description 1
- 229910052712 strontium Inorganic materials 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
- 230000001629 suppression Effects 0.000 description 1
- 238000004381 surface treatment Methods 0.000 description 1
- 229910052715 tantalum Inorganic materials 0.000 description 1
- 238000007751 thermal spraying Methods 0.000 description 1
- 229910052718 tin Inorganic materials 0.000 description 1
- 229910052721 tungsten Inorganic materials 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
- 229940007718 zinc hydroxide Drugs 0.000 description 1
- 229910021511 zinc hydroxide Inorganic materials 0.000 description 1
- 229910052726 zirconium Inorganic materials 0.000 description 1
Images
Landscapes
- Other Surface Treatments For Metallic Materials (AREA)
- Shaping Metal By Deep-Drawing, Or The Like (AREA)
Abstract
Description
本発明は、主に自動車の車体や各種自動車用部品等に適用されるような、強度が必要とされるプレス成形品、およびこのようなプレス成形品を製造するための素材として有用な表面処理鋼板に関する。 The present invention is a press-molded product that is required for strength, and is mainly applied to the body of an automobile, various automotive parts, etc., and a surface treatment useful as a material for producing such a press-molded product. It relates to steel plates.
近年、自動車の燃費向上対策の一つとして、車体の軽量化が進められており、自動車に使用される鋼板をできるだけ高強度とすることが必要となる。こうしたことから、引張強度が９８０ＭＰａを超える高強度鋼板を用いた自動車用部品が多く適用されている。一方、鋼板の高強度化に伴って、部品加工時の金型寿命低下が生じたり、スプリングバックによる部品形状のばらつきが拡大する等の問題がある。 In recent years, as one of measures for improving the fuel efficiency of automobiles, the weight of the vehicle body has been reduced, and it is necessary to make the steel plates used in the automobile as strong as possible. For these reasons, many automotive parts using high-strength steel sheets having a tensile strength exceeding 980 MPa have been applied. On the other hand, with the increase in strength of the steel sheet, there are problems such as a decrease in mold life at the time of part processing and an increase in variation in part shape due to springback.
このような課題を解決するために、鋼板をＡｃ１変態点以上の温度、即ち約９００℃程度以上の温度に加熱してオーステナイト化し、鋼板よりも低温の金型によってプレス成形する熱間プレス成形法が開発されている。こうした熱間プレス成形法によれば、鋼板の低強度状態でプレス成形されるので、部品加工時の金型寿命低下が生じたり、スプリングバックによる部品形状のばらつきが拡大するという上記問題も解消される。 In order to solve such problems, a hot press forming method in which a steel sheet is heated to a temperature above the Ac1 transformation point, that is, a temperature of about 900 ° C. or more, is austenitized, and is press-formed with a die having a temperature lower than that of the steel sheet. Has been developed. According to such a hot press forming method, since the steel sheet is press-formed in a low strength state, the above-mentioned problems that the mold life is reduced at the time of part processing and the variation of the part shape due to the spring back are solved. The
熱間プレス成形法においては、焼入れ性の良好な鋼板を用い、鋼板と金型の温度差を利用した急冷熱処理、即ち焼入れを実施することで、高強度のプレス成形品を製造できる。こうした熱間プレス成形法は、特に引張強度で１４７０ＭＰａ以上のプレス成形品を製造するための工法として広まりつつある。尚、このような熱間プレス成形法は、ホットプレス法の他、ホットスタンプ法、ホットスタンピング法、ダイクエンチ法等、様々な名称で呼ばれている。 In the hot press forming method, a high strength press-formed product can be manufactured by using a steel plate with good hardenability and performing a quenching heat treatment using a temperature difference between the steel plate and the mold, that is, quenching. Such a hot press molding method is becoming widespread as a method for producing a press molded product having a tensile strength of 1470 MPa or more. Such a hot press forming method is called by various names such as a hot stamp method, a hot stamping method, and a die quench method in addition to the hot press method.
ところで自動車用部品のうち、高耐食性が求められるサイドメンバ、サイドシル、クロスメンバ、ピラー下部等は、犠牲防食効果を発揮させることが必須となる。よって、これらの自動車用部品の製造には、部品材料として亜鉛系めっき鋼板が多用されている。 By the way, among automotive parts, side members, side sills, cross members, pillar lower parts, and the like that require high corrosion resistance must exhibit a sacrificial anticorrosive effect. Therefore, galvanized steel sheets are frequently used as component materials for the production of these automotive parts.
耐食性が要求されるような各種自動車部品は、従来から、亜鉛系めっき鋼板に冷間加工を施して製造されてきた。これに対し、近年では、亜鉛系めっき鋼板を用い、上記熱間プレス成形法によって成形することで、高強度で且つ高耐食性を示す部品が製造されつつある。 Conventionally, various automobile parts that require corrosion resistance have been manufactured by cold-working a zinc-based plated steel sheet. On the other hand, in recent years, parts having high strength and high corrosion resistance are being manufactured by using a zinc-based plated steel sheet and forming by the hot press forming method.
しかしながら、亜鉛系めっき鋼板を用いて熱間プレス成形を行うと、めっき層を構成する亜鉛が加熱によって酸化されやすくなり、プレス成形後の鋼板の表面には亜鉛の酸化皮膜（酸化亜鉛）が生成する。そのため、部品成形後に防錆のために施される電着塗装膜等の塗膜の密着性が悪化する。その結果、製品としての価値が低減し、自動車部品として適用できないという問題がある。 However, when hot press forming is performed using a zinc-based plated steel sheet, the zinc constituting the plating layer is easily oxidized by heating, and a zinc oxide film (zinc oxide) is formed on the surface of the steel sheet after press forming. To do. For this reason, the adhesion of a coating film such as an electrodeposition coating film applied for rust prevention after molding of a component is deteriorated. As a result, there is a problem that the value as a product is reduced and it cannot be applied as an automobile part.
酸化亜鉛の生成に伴う上記問題を解決する技術として、これまでにも様々提案されている。例えば、特許文献１には、亜鉛系めっき層の上に酸化亜鉛層を実質的に存在しない構成とすることによって、化成処理、塗装後の塗装密着性を確保した熱間プレス成形品が提案されている。この技術において、亜鉛系めっき層上の酸化亜鉛を低減するため、プレス成形後に、めっき層表面にショットブラストや液体ホーニングを行うことが提案されている。 Various techniques have been proposed so far to solve the above problems associated with the production of zinc oxide. For example, Patent Document 1 proposes a hot press-molded product that ensures chemical conversion treatment and coating adhesion after coating by adopting a configuration in which a zinc oxide layer does not substantially exist on the zinc-based plating layer. ing. In this technique, in order to reduce zinc oxide on the zinc-based plating layer, it has been proposed to perform shot blasting or liquid honing on the surface of the plating layer after press molding.
上記特許文献１のように、めっき層表面にショットブラストや液体ホーニングを行なうことは、それだけ生産工程数が増加することになり、また酸化亜鉛を除去するにはそれ相当の時間を要することになる。その結果、良好な生産性が実現できないという点で、実操業的な技術とはいえない。 As in Patent Document 1, performing shot blasting or liquid honing on the plating layer surface increases the number of production steps, and it takes a considerable amount of time to remove zinc oxide. . As a result, it cannot be said that it is a practical technology in that good productivity cannot be realized.
本発明は上記のような事情に鑑みてなされたものであり、その目的は、亜鉛系めっき層上の酸化亜鉛をできるだけ低減してその上に施される塗膜との良好な密着性を確保することのできるプレス成形品、およびこうしたプレス成形品を実現するためのプレス成形用表面処理鋼板を提供することにある。 The present invention has been made in view of the above circumstances, and its purpose is to reduce the zinc oxide on the zinc-based plating layer as much as possible and ensure good adhesion with the coating film applied thereon. An object of the present invention is to provide a press-formed product that can be used, and a surface-treated steel sheet for press forming for realizing such a press-formed product.
上記課題を解決し得た本発明のプレス成形用表面処理鋼板は、熱間でプレス成形してプレス成形品を得るための表面処理鋼板であって、素地鋼板の少なくとも片面に、亜鉛系めっき層を有すると共に、該亜鉛系めっき層の表面にＳｎ層を有しており、前記Ｓｎの付着量が片面あたり０．５〜２０ｇ／ｍ2である点に要旨を有する。 The surface-treated steel sheet for press forming according to the present invention that has solved the above-mentioned problems is a surface-treated steel sheet for obtaining a press-formed product by hot press forming, and a zinc-based plating layer on at least one surface of the base steel sheet And having a Sn layer on the surface of the zinc-based plating layer, the gist of which is that the amount of Sn deposited is 0.5 to 20 g / m 2 per side.
本発明のプレス成形用表面処理鋼板において、前記Ｓｎ層としては、Ｓｎめっき層、Ｓｎ溶射層またはＳｎスパッタ蒸着層が例示できる。また前記亜鉛系めっき層としては、亜鉛めっき層、合金化された亜鉛めっき層または亜鉛合金めっき層が例示できる。 In the surface-treated steel sheet for press forming of the present invention, examples of the Sn layer include a Sn plating layer, a Sn sprayed layer, and a Sn sputter deposition layer. Examples of the zinc-based plating layer include a zinc plating layer, an alloyed zinc plating layer, and a zinc alloy plating layer.
本発明のプレス成形用表面処理鋼板で用いる素地鋼板は、その化学成分組成については、特に限定されないが、プレス成形品としての基本的な機械的特性を発揮させるためには、下記の化学成分組成を有するものが好ましい。即ち、質量％で、
Ｃ ：０．１５〜０．４％、
Ｓｉ：０％超、３％以下、
Ｍｎ：０〜３％、
Ａｌ：０％超、０．１％以下、および
Ｂ ：０〜０．０１％
を含有し、残部が鉄および不可避不純物からなる化学成分組成を有する素地鋼板であることが好ましい。
The base steel sheet used in the surface-treated steel sheet for press molding of the present invention is not particularly limited in terms of its chemical composition, but in order to exhibit basic mechanical properties as a press-formed product, the following chemical composition is used: Those having the following are preferred. That is, in mass%,
C: 0.15-0.4%,
Si: more than 0%, 3% or less,
Mn: 0 to 3%,
Al: more than 0%, 0.1% or less, and B: 0 to 0.01%
It is preferable that the base steel plate has a chemical composition composed of iron and inevitable impurities.
前記素地鋼板は、必要によって、更に、質量％で（ａ）Ｔｉ：０％超、０．１％以下、（ｂ）Ｃｒ、ＮｉおよびＣｕよりなる群から選択される１種以上：合計で０％超、１％以下等を含有させることも有用である。 If necessary, the base steel sheet is further, in mass%, (a) Ti: more than 0%, 0.1% or less, (b) one or more selected from the group consisting of Cr, Ni and Cu: 0 in total It is also useful to contain more than%, 1% or less.
本発明には、上記プレス成形用表面処理鋼板を熱間プレス成形して得られたプレス成形品も包含される。 The present invention also includes a press-formed product obtained by hot press-forming the surface-treated steel sheet for press forming.
本発明には、素地鋼板の少なくとも片面に、亜鉛系めっき層を有すると共に、該亜鉛系めっき層の表面に二酸化スズ層を有するプレス成形品も包含される。 The present invention includes a press-formed product having a zinc-based plating layer on at least one surface of the base steel sheet and a tin dioxide layer on the surface of the zinc-based plating layer.
本発明によれば、素地鋼板の少なくとも片面に、亜鉛系めっき層を有すると共に、該亜鉛系めっき層の表面に所定量のＳｎ層を有する表面処理鋼板を採用することによって、熱間プレス成形時での亜鉛系めっき層における酸化を防止し、良好な塗膜密着性を確保することのできるプレス成形品が得られる。 According to the present invention, by adopting a surface-treated steel sheet having a zinc-based plating layer on at least one surface of the base steel sheet and having a predetermined amount of Sn layer on the surface of the zinc-based plating layer, A press-molded product can be obtained which prevents oxidation in the zinc-based plating layer and can ensure good coating film adhesion.
本明細書において塗膜密着性とは、亜鉛系めっき層の上に通常施される電着塗装膜等の塗膜との密着性を意味する。亜鉛系めっき層の上には、通常、耐食性向上のためリン酸亜鉛皮膜等の化成処理皮膜と、その上に上記塗膜が形成される。よって、本発明における塗膜密着性とは、上記化成処理皮膜を有する場合は、上記化成処理皮膜を介した上での塗膜との密着性を意味する。尚、化成処理皮膜は当該皮膜を構成する結晶のアンカー効果により、上記塗膜との密着性は良好であるため、化成処理皮膜・塗膜間での密着性が問題になることはない。 In the present specification, the coating film adhesion means adhesion with a coating film such as an electrodeposition coating film usually applied on the zinc-based plating layer. On the zinc-based plating layer, a chemical conversion treatment film such as a zinc phosphate film is usually formed on the zinc-based plating layer, and the coating film is formed thereon. Therefore, the coating film adhesiveness in this invention means the adhesiveness with the coating film through the said chemical conversion treatment film, when it has the said chemical conversion treatment film. In addition, since the chemical conversion treatment film has good adhesion to the coating film due to the anchor effect of the crystals constituting the film, the adhesion between the chemical conversion treatment film and the coating film does not become a problem.
本発明者らは、亜鉛系めっき鋼板を使用して熱間プレスを行なったプレス成形品において、亜鉛系めっき層中の酸化亜鉛が塗膜密着性を劣化させる原因について検討した。その結果、次のような知見が得られた。 The inventors of the present invention have studied the cause of the deterioration of coating film adhesion due to zinc oxide in a zinc-based plating layer in a press-formed product that has been hot-pressed using a zinc-based plated steel sheet. As a result, the following knowledge was obtained.
プレス成形品が、組立て、塗装されて自動車として使用される場合、雨水等が浸潤したときに酸化亜鉛が存在すると、塗膜下の腐食が発生しやすい状態となる。特に海塩や路上に散布された融雪剤に含まれる塩類を含んだ塩水腐食環境において、塗膜下に発生した亜鉛錆部では、ｐＨ＞１０の塩基性となり、酸化物や水酸化物からなる亜鉛錆部は溶解してしまう。このように、特に塩化物イオンを含む腐食環境下において塗膜密着性が顕著に劣化する理由は、塗膜に浸潤した水、および水に含まれる溶存酸素と塩化物イオンにより、酸化亜鉛の下に存在する亜鉛系めっき層の腐食が進行するためと考えられる。 When a press-molded product is assembled, painted and used as an automobile, if zinc oxide is present when rainwater or the like is infiltrated, corrosion under the coating film is likely to occur. In particular, in a salt water corrosive environment containing salt contained in sea salt or snow melting agent sprayed on the road, the zinc rust generated under the coating film becomes basic with a pH> 10 and consists of oxides and hydroxides. Zinc rust will dissolve. As described above, the reason why the coating film adhesion deteriorates remarkably in a corrosive environment containing chloride ions is because the water infiltrated into the coating film and the dissolved oxygen and chloride ions contained in the water cause the adhesion under the zinc oxide. This is thought to be due to the progress of corrosion of the zinc-based plating layer present in the steel.
そこで本発明者らは、上記のような腐食環境下であっても、酸化亜鉛の生成を抑制し得る熱間プレス成形用鋼板の構成について、様々な角度から検討した。その結果、亜鉛系めっき層の上（表面）にＳｎ層を有する構成とすることによって、上記のような腐食環境下での塗膜密着性が改善できることを見出し、本発明を完成した。上記Ｓｎ層は後記する方法で比較的簡単に形成することができ、また熱間プレス成形後に除錆等の余分な工程を経なくても良いので、プレス成形品を製造するときの生産性も良好となる。しかも、Ｓｎ層と亜鉛系めっき層との密着性は、基本的に良好である。 Therefore, the present inventors have studied the structure of a hot press-formed steel sheet that can suppress the formation of zinc oxide even from the above-mentioned corrosive environment from various angles. As a result, the inventors have found that the coating film adhesion under the corrosive environment as described above can be improved by forming the Sn layer on the zinc-based plating layer (surface), thereby completing the present invention. The Sn layer can be formed relatively easily by the method described later, and it is not necessary to go through extra steps such as rust removal after hot press forming, so productivity when producing press-formed products is also achieved. It becomes good. Moreover, the adhesion between the Sn layer and the zinc-based plating layer is basically good.
亜鉛系めっき層の上にＳｎ層を有する構成とすることによって、塗膜密着性が向上する理由については、その全てを解明し得た訳ではないが、おそらく以下のような機構によるものと推定される。 The reason why the coating film adhesion is improved by having the Sn layer on the zinc-based plating layer has not been fully clarified, but it is presumably due to the following mechanism. Is done.
熱間プレス成形時に亜鉛系めっき層上のＳｎは、プレス時の雰囲気中に含まれる酸素によって酸化されて二酸化スズに変化する。塗膜密着性の劣化が顕著に発生する塩基性環境下では、二酸化スズは、亜鉛の酸化物や水酸化物よりも安定であるため、錆の溶解にともなう塗膜下での腐食の進行が抑制され、塗膜密着性が向上すると考えられる。 At the time of hot press forming, Sn on the zinc-based plating layer is oxidized by oxygen contained in the atmosphere at the time of pressing and changes to tin dioxide. In a basic environment where coating film adhesion deteriorates remarkably, tin dioxide is more stable than zinc oxide or hydroxide, and therefore, corrosion under the coating film proceeds as rust dissolves. It is considered that the coating film adhesion is improved.
本明細書において、Ｓｎ層とは、Ｓｎを含む層であれば特に限定されず、純Ｓｎ、Ｓｎを主体とする合金（例えば、Ｓｎを約５０質量％以上含むＳｎ−Ｃｕ系合金、Ｓｎ−Ｐｂ系合金）等が挙げられる。 In this specification, the Sn layer is not particularly limited as long as it is a layer containing Sn, and is pure Sn, an alloy mainly composed of Sn (for example, Sn—Cu based alloy containing about 50 mass% or more of Sn, Sn— Pb-based alloy).
上記Ｓｎ層による塗膜密着性向上効果を十分に発揮させるためには、Ｓｎ（金属Ｓｎ量換算）の付着量（以下、「Ｓｎ付着量」と呼ぶことがある）を、片面あたりで０．５ｇ／ｍ2以上とする必要がある。好ましくは１．０ｇ／ｍ2以上であり、より好ましくは１．５ｇ／ｍ2以上である。上記Ｓｎ付着量は、片面あたりの量である。尚、Ｓｎ層がＳｎ合金からなる場合には、上記「Ｓｎ付着量」は、合金中に含まれるＳｎのみの付着量（金属Ｓｎ量換算）を意味する。 In order to sufficiently exhibit the effect of improving the adhesion of the coating film by the Sn layer, the adhesion amount of Sn (in terms of metal Sn amount) (hereinafter sometimes referred to as “Sn adhesion amount”) is set to 0. It is necessary to be 5 g / m 2 or more. Preferably it is 1.0 g / m 2 or more, more preferably 1.5 g / m 2 or more. The Sn adhesion amount is an amount per one side. In the case where the Sn layer is made of an Sn alloy, the “Sn adhesion amount” means an adhesion amount of only Sn contained in the alloy (in terms of metal Sn amount).
本発明の表面処理鋼板では、両面の耐食性が必要となる場合もある。その場合には、表面処理鋼板は素地鋼板の両面に亜鉛系めっき層が形成されると共に、夫々の亜鉛系めっき層上に上記した付着量のＳｎ層が形成される。夫々の面でのＳｎ付着量は、最終製品であるプレス成形品の要求特性に応じて、同一であっても良いし異なっていても良い。 In the surface-treated steel sheet of the present invention, corrosion resistance on both sides may be required. In that case, the surface-treated steel sheet has a zinc-based plating layer formed on both sides of the base steel sheet, and the Sn layer having the above adhesion amount is formed on each zinc-based plating layer. The Sn adhesion amount on each surface may be the same or different depending on the required characteristics of the press-formed product that is the final product.
Ｓｎ付着量の上限は、塗膜密着性への寄与を考慮すると特に限定されないが、Ｓｎ付着量が多すぎると熱間プレス成形時に金型へのＳｎ凝着が発生することがある。これは、Ｓｎ付着量が多くなりすぎると、熱間プレス成形時に低融点の金属Ｓｎが多量に金型表面に残存するためと推定される。このため、熱間プレス成形前の加熱条件、即ち加熱温度、所定温度までの加熱時間、加熱パターン等に応じてＳｎ付着量の上限を設ける必要がある。 The upper limit of the Sn adhesion amount is not particularly limited considering the contribution to the coating film adhesion, but if the Sn adhesion amount is too large, Sn adhesion to the mold may occur during hot press molding. This is presumably because if the Sn adhesion amount is too large, a large amount of low melting point metal Sn remains on the mold surface during hot press molding. For this reason, it is necessary to provide the upper limit of Sn adhesion amount according to the heating conditions before hot press forming, that is, the heating temperature, the heating time to a predetermined temperature, the heating pattern, and the like.
例えば、室温から９００℃程度までを、２分〜５分程度かけて比較的ゆっくりと加熱する場合には、Ｓｎ付着量は２０ｇ／ｍ2以下とする必要がある。好ましくは１５ｇ／ｍ2以下であり、より好ましくは１０ｇ／ｍ2以下である。また室温から９００℃程度までを３秒〜１分間かけて比較的急速に加熱する場合には、Ｓｎ付着量はできるだけ少なくても良く、Ｓｎ付着量は１０ｇ／ｍ2以下であることが好ましい。より好ましくは５ｇ／ｍ2以下である。 For example, when heating from room temperature to about 900 ° C. relatively slowly over about 2 to 5 minutes, the Sn deposition amount needs to be 20 g / m 2 or less. Preferably it is 15 g / m 2 or less, more preferably 10 g / m 2 or less. When heating from room temperature to about 900 ° C. relatively rapidly over 3 seconds to 1 minute, the Sn adhesion amount may be as small as possible, and the Sn adhesion amount is preferably 10 g / m 2 or less. More preferably, it is 5 g / m 2 or less.
Ｓｎ層の形成方法としては、電気めっき法や溶融めっき法等のめっき法の他、溶射法等が挙げられる。これらの方法によって、Ｓｎめっき層、Ｓｎ溶射層を形成することによって、所望とする特性を発揮するＳｎ層が形成できる。或いは、鋼板をブランクに切断してから、スパッタ蒸着によってＳｎスパッタ蒸着層を形成することもできる。これらのうち、連続ラインで鋼板を製造する場合には、安価に均一なＳｎ層が得られるという観点からすれば、電気めっき法や溶融めっき法等のめっき法を採用することが望ましい。 Examples of the method for forming the Sn layer include a thermal spraying method and the like in addition to a plating method such as an electroplating method and a hot dipping method. By forming the Sn plating layer and the Sn sprayed layer by these methods, an Sn layer that exhibits desired characteristics can be formed. Alternatively, the Sn sputter deposition layer can be formed by sputtering deposition after cutting the steel plate into a blank. Among these, when manufacturing a steel plate with a continuous line, it is desirable to employ plating methods such as an electroplating method and a hot dipping method from the viewpoint that a uniform Sn layer can be obtained at a low cost.
一方、素地鋼板表面に形成される亜鉛系めっき層の種類は特に限定されず、亜鉛めっき層、合金化された亜鉛めっき層または亜鉛合金めっき層等を採用することができる。上記亜鉛めっき層としては、例えば純亜鉛めっき層の他、少量のＡｌ等を含む亜鉛めっき層が挙げられる。上記合金化された亜鉛めっき層は、上記亜鉛めっき層を合金化することによって得られるものである。また、上記亜鉛合金めっき層は、亜鉛を主体とし、他の合金元素を含むものであり、例えばＦｅ−Ｚｎ合金めっきやＺｎ−Ｎｉ合金めっき等が挙げられる。この亜鉛合金めっき層は、Ｚｎを７５質量％以上含むことが好ましい。尚、上記Ｓｎ層を形成する方法として電気めっき法を採用する場合には、その下地層としてＺｎ−Ｎｉ合金めっき層等の亜鉛合金めっき層を採用することが、Ｓｎ層形成時におけるウィスカの生成抑制という観点から好ましい。 On the other hand, the type of the zinc-based plating layer formed on the surface of the base steel plate is not particularly limited, and a zinc plating layer, an alloyed zinc plating layer, a zinc alloy plating layer, or the like can be employed. Examples of the zinc plating layer include a pure zinc plating layer and a zinc plating layer containing a small amount of Al. The alloyed galvanized layer is obtained by alloying the galvanized layer. The zinc alloy plating layer is mainly composed of zinc and contains other alloy elements, and examples thereof include Fe—Zn alloy plating and Zn—Ni alloy plating. This zinc alloy plating layer preferably contains 75% by mass or more of Zn. When the electroplating method is adopted as the method for forming the Sn layer, it is possible to generate whiskers when forming the Sn layer by adopting a zinc alloy plating layer such as a Zn-Ni alloy plating layer as the underlying layer. It is preferable from the viewpoint of suppression.
上記亜鉛系めっき層の形成方法は特に限定されず、電気亜鉛めっき法、溶融亜鉛めっき法の他、合金化溶融亜鉛めっき法を採用でき、めっき層の種類やめっき膜厚に応じて適宜採用すれば良い。 The method for forming the zinc-based plating layer is not particularly limited. In addition to the electrogalvanizing method and the hot dip galvanizing method, an alloyed hot dip galvanizing method can be adopted, and it can be appropriately employed depending on the type of plating layer and the plating film thickness. It ’s fine.
亜鉛系めっき層を形成するときのめっき条件は特に限定されず、一般的に行われているめっき条件に従えば良い。例えば溶融めっき層を形成するときのめっき条件は、めっき槽の浴温度は４２０〜４８０℃程度、浸漬時間は１〜１０秒程度である。まためっき処理後に更に合金化処理を行うときの条件は、例えば大気や窒素雰囲気下で、好ましくは４７０℃以上、６５０℃以下で、５秒以上、１０分以下で保持して行うことができる。より好ましい温度は、４９０℃以上、６００℃以下であり、より好ましい保持時間は、１０秒以上、５分以下である。また合金化温度から室温までの冷却条件は、特に問わないが、通常は平均冷却速度１０〜５０℃／秒程度の冷却を行う。 The plating conditions for forming the zinc-based plating layer are not particularly limited, and may be in accordance with generally performed plating conditions. For example, as for the plating conditions for forming the hot-dip plating layer, the bath temperature of the plating tank is about 420 to 480 ° C., and the immersion time is about 1 to 10 seconds. The conditions for further alloying treatment after the plating treatment are, for example, in the air or nitrogen atmosphere, preferably 470 ° C. or more and 650 ° C. or less, and held for 5 seconds or more and 10 minutes or less. A more preferable temperature is 490 ° C. or more and 600 ° C. or less, and a more preferable holding time is 10 seconds or more and 5 minutes or less. The cooling condition from the alloying temperature to room temperature is not particularly limited. Usually, cooling is performed at an average cooling rate of about 10 to 50 ° C./second.
亜鉛系めっき層の付着量（以下、「亜鉛めっき付着量」と呼ぶことがある）は、耐食性を確保するために片面あたり３０ｇ／ｍ2以上であることが好ましい。亜鉛めっき付着量を片面あたり３０ｇ／ｍ2以上とすることで、十分な耐食性を得ることができる。より好ましくは４０ｇ／ｍ2以上であり、更に好ましくは５０ｇ／ｍ2以上である。 The adhesion amount of the zinc-based plating layer (hereinafter sometimes referred to as “zinc plating adhesion amount”) is preferably 30 g / m 2 or more per side in order to ensure corrosion resistance. Sufficient corrosion resistance can be obtained by setting the amount of galvanized adhesion to 30 g / m 2 or more per side. More preferably, it is 40 g / m < 2 > or more, More preferably, it is 50 g / m < 2 > or more.
一方、亜鉛めっき付着量が多すぎても、その量に応じた耐食性が発揮されるとは限らず、無駄にコストが大きくなるため、目安として片面あたり１００ｇ／ｍ2以下であることが好ましい。亜鉛系めっき層が素地鋼板の両面に形成される場合には、最終製品であるプレス成形品の要求特性に応じて、夫々の面での亜鉛めっき付着量は、上記の範囲内で同一であっても良いし異なっていても良い。 On the other hand, even if the amount of galvanized coating is too large, the corrosion resistance according to the amount is not necessarily exhibited, and the cost is increased unnecessarily, so that it is preferably 100 g / m 2 or less per side as a guide. When the zinc-based plating layer is formed on both sides of the base steel plate, the amount of galvanized coating on each side is the same within the above range, depending on the required characteristics of the press-formed product that is the final product. May be different or different.
本発明の表面処理鋼板に用いられる素地鋼板の種類は特に限定されず、熱延鋼板または冷延鋼板、更には必要に応じてこれら鋼板に焼鈍等の熱処理を施した鋼板のいずれも採用できる。具体的には、（１）熱延鋼板、または当該熱延鋼板の表面に形成される酸化皮膜を除去した鋼板、（２）上記（１）の熱延鋼板を更に冷間圧延した冷延鋼板、（３）前記（１）、（２）の各鋼板を更に熱処理した鋼板、（４）前記（３）での熱処理後に表面を洗浄した鋼板等を素地鋼板として用いることができる。尚、上記焼鈍等の熱処理では、素地鋼板の硬さが調節され、製造性、通板安定性等を改善できる。 The kind of the base steel sheet used for the surface-treated steel sheet of the present invention is not particularly limited, and any of a hot-rolled steel sheet or a cold-rolled steel sheet, and further a steel sheet obtained by subjecting these steel sheets to heat treatment such as annealing can be adopted. Specifically, (1) a hot-rolled steel sheet or a steel sheet from which an oxide film formed on the surface of the hot-rolled steel sheet has been removed, and (2) a cold-rolled steel sheet obtained by further cold rolling the hot-rolled steel sheet of (1) above. (3) A steel plate obtained by further heat-treating each steel plate of (1) and (2), (4) a steel plate whose surface is cleaned after the heat treatment in (3), and the like can be used as the base steel plate. In the heat treatment such as annealing, the hardness of the base steel sheet is adjusted, and the productivity, sheet feeding stability, and the like can be improved.
上記のうち例えば熱延鋼板を製造する方法は特に限定されないが、具体例としては、熱間圧延前の加熱温度：約１１００〜１３００℃、仕上げ圧延温度：８００〜９５０℃、巻取り温度：５００〜７００℃等の条件を採用することができる。また上記冷延鋼板は、前記熱延鋼板に対し、例えば冷延率：３〜７０％程度の冷間圧延を施して得ることができる。 Of these, for example, a method for producing a hot-rolled steel sheet is not particularly limited, but specific examples include heating temperature before hot rolling: about 1100 to 1300 ° C., finish rolling temperature: 800 to 950 ° C., winding temperature: 500. Conditions such as ˜700 ° C. can be employed. The cold-rolled steel sheet can be obtained by subjecting the hot-rolled steel sheet to cold rolling with a cold rolling ratio of about 3 to 70%, for example.
上記素地鋼板の板厚は特に限定されず、熱延鋼板の場合では、２．０〜３．５ｍｍ程度であり、冷延鋼板の場合には、０．８〜１．８ｍｍ程度である。 The plate thickness of the base steel plate is not particularly limited, and is about 2.0 to 3.5 mm in the case of a hot rolled steel plate, and about 0.8 to 1.8 mm in the case of a cold rolled steel plate.
上記素地鋼板は、熱間プレス成形品を製造するための高強度鋼板として通常の化学成分組成を有するものであれば良いが、Ｃ、Ｓｉ、Ｍｎ、ＡｌおよびＢについては、適切な範囲に調整するのが良い。これらの化学成分の好ましい範囲およびその設定理由は下記の通りである。尚、本明細書では、化学成分組成について「％」とは、質量％を意味する。 The base steel plate may be any material having a normal chemical composition as a high-strength steel plate for producing hot press-formed products, but C, Si, Mn, Al and B are adjusted to an appropriate range. Good to do. The preferred ranges of these chemical components and the reasons for setting them are as follows. In the present specification, “%” for the chemical component composition means mass%.
（Ｃ：０．１５〜０．４％）
Ｃは、熱間プレス成形により得られるプレス成形品の強度を確保する上で重要な元素である。こうした観点からＣ量は、０．１５％以上とすることが好ましい。より好ましくは０．１８％以上であり、更に好ましくは０．２０％以上である。一方、Ｃ量が過剰になると、プレス成形品の溶接性やプレス成形品製造時の延性の確保が困難となる。よってＣ量は、０．４％以下とすることが好ましい。より好ましくは０．３８％以下、更に好ましくは０．３５％以下である。
(C: 0.15-0.4%)
C is an important element for securing the strength of a press-molded product obtained by hot press molding. From this point of view, the C content is preferably 0.15% or more. More preferably, it is 0.18% or more, More preferably, it is 0.20% or more. On the other hand, when the amount of C is excessive, it becomes difficult to ensure the weldability of the press-formed product and the ductility during manufacture of the press-formed product. Therefore, the C amount is preferably 0.4% or less. More preferably, it is 0.38% or less, More preferably, it is 0.35% or less.
（Ｓｉ：０％超、３％以下）
Ｓｉは、熱間プレス成形時に残留オーステナイトを形成させる作用を発揮する。この残留オーステナイトは、塑性変形中にマルテンサイトに変態することで、加工硬化率を上昇させる変態誘起塑性を発揮し、最終製品であるプレス成形品の延性、耐衝撃性が向上する。またＳｉは、固溶強化によって、延性をあまり劣化させずに強度を高める作用も発揮する。こうした作用は、Ｓｉ量が増加するにつれて大きくなるが、その作用を有効に発揮させるためには、Ｓｉ量は０．５％以上とすることが好ましい。より好ましくは１％以上であり、更に好ましくは１．２％以上である。一方、Ｓｉ量が過剰になると、プレス成形品の靭性が劣化する。よってＳｉ量は、３％以下とすることが好ましい。より好ましくは２．５％以下であり、更に好ましくは２％以下であり、特に好ましくは１．８％以下である。
(Si: over 0%, 3% or less)
Si exhibits the effect of forming retained austenite during hot press molding. This retained austenite transforms into martensite during plastic deformation, thereby exhibiting transformation-induced plasticity that increases the work hardening rate, and improves the ductility and impact resistance of the press-formed product that is the final product. Si also exhibits the effect of increasing the strength without significantly degrading the ductility by solid solution strengthening. Such an effect increases as the Si amount increases, but in order to effectively exhibit the effect, the Si amount is preferably 0.5% or more. More preferably, it is 1% or more, More preferably, it is 1.2% or more. On the other hand, when the amount of Si becomes excessive, the toughness of the press-formed product deteriorates. Therefore, the Si amount is preferably 3% or less. More preferably, it is 2.5% or less, More preferably, it is 2% or less, Most preferably, it is 1.8% or less.
（Ｍｎ：０〜３％）
Ｍｎは、必要によって添加される元素であるが、素地鋼板の焼入れ性を高め、加熱後の冷却中に、フェライト、パーライト、ベイナイトの生成を抑制し、高強度の確保に寄与する元素である。こうした効果を有効に発揮させるには、Ｍｎ量は０．５％以上とすることが好ましい。より好ましくは０．８％以上、更に好ましくは１．０％以上である。一方、熱間圧延の負荷等を考慮すると、Ｍｎ量は、３％以下とすることが好ましく、より好ましくは２．８％以下、更に好ましくは２．５％以下、特に好ましくは２．１％以下である。
(Mn: 0 to 3%)
Mn is an element added as necessary, but is an element that improves the hardenability of the base steel sheet, suppresses the formation of ferrite, pearlite, and bainite during cooling after heating, and contributes to securing high strength. In order to exhibit such an effect effectively, the amount of Mn is preferably 0.5% or more. More preferably, it is 0.8% or more, More preferably, it is 1.0% or more. On the other hand, considering the hot rolling load, the Mn content is preferably 3% or less, more preferably 2.8% or less, still more preferably 2.5% or less, and particularly preferably 2.1%. It is as follows.
（Ａｌ：０％超、０．１％以下）
Ａｌは、脱酸元素として有用な元素である。こうした観点から、Ａｌを好ましくは０％超、より好ましくは０．０１％以上含み得る。しかしながら、Ａｌ量が過剰になるとＡｌ2Ｏ3の生成により延性等の劣化が生じ得る。よってＡｌ量は、０．１％以下であることが好ましく、より好ましくは０．０８％以下であり、更に好ましくは０．０５％以下である。
(Al: more than 0%, 0.1% or less)
Al is an element useful as a deoxidizing element. From such a viewpoint, Al may be contained preferably in an amount of more than 0%, more preferably 0.01% or more. However, when the amount of Al becomes excessive, deterioration of ductility and the like may occur due to generation of Al 2 O 3 . Therefore, the Al content is preferably 0.1% or less, more preferably 0.08% or less, and still more preferably 0.05% or less.
（Ｂ：０〜０．０１％）
Ｂは、必要によって添加される元素であるが、鋼板の焼入れ性を向上させるために有効な元素である。こうした効果を有効に発揮させるためには、Ｂ量は０．０００２％以上とすることが好ましく、より好ましくは０．０００３％以上、更に好ましくは０．０００５％以上である。一方、Ｂ量が過剰になるとその効果が飽和するため、Ｂ量は０．０１％以下とすることが好ましく、より好ましくは０．００８％以下、更に好ましくは０．００５％以下である。
(B: 0-0.01%)
B is an element added as necessary, but is an effective element for improving the hardenability of the steel sheet. In order to effectively exhibit these effects, the B content is preferably 0.0002% or more, more preferably 0.0003% or more, and still more preferably 0.0005% or more. On the other hand, since the effect is saturated when the amount of B becomes excessive, the amount of B is preferably 0.01% or less, more preferably 0.008% or less, and still more preferably 0.005% or less.
本発明で用いる素地鋼板の基本的な化学成分組成は、上記の通りであり、残部は実質的に鉄である。尚、「実質的に鉄」とは、鉄以外にも本発明の素地鋼板、即ち表面処理鋼板の特性を阻害しない程度の微量成分、例えばＭｇ、Ｃａ、Ｓｒ、Ｂａの他、Ｌａ等の希土類元素、およびＺｒ、Ｈｆ、Ｔａ、Ｗ、Ｍｏの炭化物形成元素も許容できる他、Ｐ、Ｓ、Ｎ、Ｏ、Ｈ等の不可避不純物も含み得る。また、必要によって、更に（ａ）Ｔｉ：０％超、０．１％以下、（ｂ）Ｃｒ、ＮｉおよびＣｕよりなる群から選択される１種以上：合計で０％超、１％以下等を含有させることも有用であり、含有される元素の種類に応じて、プレス成形品の特性が更に改善される。これらの元素を含有させるときの好ましい範囲およびその設定理由は下記の通りである。 The basic chemical composition of the base steel sheet used in the present invention is as described above, and the balance is substantially iron. In addition, “substantially iron” means a trace component that does not hinder the properties of the base steel sheet of the present invention, that is, the surface-treated steel sheet, in addition to iron, for example, Mg, Ca, Sr, Ba, and other rare earth elements such as La. In addition to the elements and carbide forming elements of Zr, Hf, Ta, W, and Mo, they can also contain inevitable impurities such as P, S, N, O, and H. Further, if necessary, (a) Ti: more than 0%, 0.1% or less, (b) one or more selected from the group consisting of Cr, Ni and Cu: in total, more than 0%, 1% or less, etc. It is also useful to contain, and the properties of the press-formed product are further improved depending on the type of element contained. Preferred ranges when these elements are contained and the setting reasons are as follows.
（Ｔｉ：０％超、０．１％以下）
Ｔｉは、Ｎを固定し、Ｂを固溶状態で維持させることで焼入れ性の改善効果を発揮させる。こうした効果を発揮させるためには、Ｔｉは０．０４％以上含有させることが好ましい。より好ましくは０．０５％以上であり、更に好ましく０．０６％以上である。しかしながら、Ｔｉ量が過剰になって０．１％を超えると、ＴｉＣを多量に形成し、析出強化により強度が上昇するが延性が低下する。こうしたことから、Ｔｉを含有させるときの上限は０．１％以下とすることが好ましい。より好ましくは０．０９％以下であり、更に好ましくは０．０８％以下である。
(Ti: over 0%, 0.1% or less)
Ti fixes N and maintains B in a solid solution state, thereby exerting an effect of improving hardenability. In order to exhibit such an effect, it is preferable to contain Ti 0.04% or more. More preferably, it is 0.05% or more, More preferably, it is 0.06% or more. However, when the amount of Ti becomes excessive and exceeds 0.1%, a large amount of TiC is formed and the strength increases due to precipitation strengthening, but the ductility decreases. For these reasons, the upper limit when Ti is contained is preferably 0.1% or less. More preferably, it is 0.09% or less, More preferably, it is 0.08% or less.
（Ｃｒ、ＮｉおよびＣｕよりなる群から選択される１種以上：合計で０％超、１％以下）
Ｃｒ、ＮｉおよびＣｕは、フェライト変態、パーライト変態およびベイナイト変態を抑制するため、加熱後の冷却中に、フェライト、パーライトおよびベイナイトの生成を防止し、残留オーステナイトの確保に有効に作用する。こうした効果を発揮させるためには、合計で０．０１％以上含有させることが好ましいが、合金添加コストが上昇することから、合計で１％以下とすることが好ましい。これらの元素含有量のより好ましい下限は、合計で０．０５％以上であり、更に好ましくは０．０６％以上である。より好ましい上限は、合計で０．９％以下であり、更に好ましくは０．８％以下である。
(One or more selected from the group consisting of Cr, Ni, and Cu: total of more than 0% and 1% or less)
Since Cr, Ni, and Cu suppress ferrite transformation, pearlite transformation, and bainite transformation, they prevent the formation of ferrite, pearlite, and bainite during cooling after heating, and effectively act to secure retained austenite. In order to exert such effects, the total content is preferably 0.01% or more. However, the alloy addition cost is increased, so that the total content is preferably 1% or less. The more preferable lower limit of the content of these elements is 0.05% or more in total, and further preferably 0.06% or more. A more preferable upper limit is 0.9% or less in total, and further preferably 0.8% or less.
本発明のプレス成形品は、素地鋼板の少なくとも片面に、亜鉛系めっき層を有すると共に、該亜鉛系めっき層の上に二酸化スズ層を有する。上記二酸化スズ層の上には、部品としての耐食性や塗装の均一性を確保するためのカチオン電着塗装等の処理により塗膜が形成される。また必要に応じて、上記塗膜の下地層として耐食性向上のために通常用いられるリン酸亜鉛皮膜等の化成処理皮膜が施されても良い。前述したとおり化成処理皮膜と上記塗装膜との密着性は良好であるため、リン酸亜鉛皮膜処理が施された場合であっても、二酸化スズ層による塗膜密着性向上効果は十分に発揮される。 The press-formed product of the present invention has a zinc-based plating layer on at least one surface of a base steel plate and also has a tin dioxide layer on the zinc-based plating layer. A coating film is formed on the tin dioxide layer by a treatment such as cationic electrodeposition coating for ensuring corrosion resistance as a part and uniformity of coating. Further, if necessary, a chemical conversion treatment film such as a zinc phosphate film that is usually used for improving the corrosion resistance may be applied as an undercoat layer of the coating film. As described above, since the adhesion between the chemical conversion coating and the coating film is good, the effect of improving the coating adhesion by the tin dioxide layer is sufficiently exhibited even when the zinc phosphate coating is applied. The
以下、実施例を挙げて本発明をより具体的に説明する。本発明は以下の実施例によって制限を受けるものではなく、前記、後記の趣旨に適合し得る範囲で適当に変更を加えて実施することも勿論可能であり、それらはいずれも本発明の技術的範囲に含まれる。 Hereinafter, the present invention will be described more specifically with reference to examples. The present invention is not limited by the following examples, and can of course be implemented with appropriate modifications within a range that can be adapted to the above-described gist. Included in the range.
下記表１に示したＡ〜Ｇの化学成分組成を有する鋼材を溶製し、鋳造してスラブを得た後、熱間圧延を行って板厚：２．３ｍｍの熱延鋼板を得た。この熱延鋼板に冷間圧延を行って板厚：１．４ｍｍの冷延鋼板を作製した。該冷延鋼板に対して、後記表２、３に示す条件で溶融亜鉛めっき処理を行い、鋼板の両面に亜鉛めっき層を有する亜鉛めっき鋼板を作製した。また、一部の材料については溶融めっき浴から引き上げた後、直ちに合金化処理を施して、合金化溶融亜鉛めっき鋼板を作製した。 Steel materials having chemical composition compositions A to G shown in Table 1 below were melted and cast to obtain a slab, followed by hot rolling to obtain a hot-rolled steel plate having a thickness of 2.3 mm. The hot-rolled steel sheet was cold-rolled to produce a cold-rolled steel sheet having a thickness of 1.4 mm. The cold-rolled steel sheet was hot dip galvanized under the conditions shown in Tables 2 and 3 below to produce a galvanized steel sheet having galvanized layers on both surfaces of the steel sheet. Further, some of the materials were pulled out of the hot dipping bath and immediately subjected to an alloying treatment to produce an alloyed hot dip galvanized steel sheet.
前記亜鉛めっき処理と合金化処理は、雰囲気制御が可能で加熱冷却機構と亜鉛めっき浴となる坩堝を備え、めっき処理、合金化処理が一貫工程で可能な実験炉を用いて行った。前記めっき処理は、４６０℃の０．１３％Ａｌ−Ｚｎ浴に３秒間浸漬した。前記合金化処理は５％Ｈ2−Ｎ2（露点−４５℃）の雰囲気で、５５０℃で２０秒間保持することで行った。合金化処理後の冷却はＡｒガスの吹き付けにより行った。このときの冷却開始から室温までの平均冷却速度は1０〜１５℃／秒とした。 The galvanizing treatment and the alloying treatment were performed using an experimental furnace that can control the atmosphere, has a heating / cooling mechanism and a crucible serving as a galvanizing bath, and can perform the plating treatment and alloying treatment in an integrated process. The plating treatment was immersed in a 0.13% Al—Zn bath at 460 ° C. for 3 seconds. The alloying treatment was performed by holding at 550 ° C. for 20 seconds in an atmosphere of 5% H 2 —N 2 (dew point −45 ° C.). Cooling after the alloying treatment was performed by blowing Ar gas. The average cooling rate from the start of cooling to room temperature at this time was set to 10 to 15 ° C./second.
亜鉛めっき鋼板および合金化亜鉛めっき鋼板の亜鉛めっき付着量は、ガスワイピングにより調整し、ＩＣＰ（Ｉｎｄｕｃｔｉｖｅｌｙ Ｃｏｕｐｌｅｄ Ｐｌａｓｍａ：誘導結合プラズマ）発光分光分析により測定した。亜鉛めっき付着量は片面あたり、３１〜７３ｇ／ｍ2とした。 The zinc coating amount of the galvanized steel sheet and the alloyed galvanized steel sheet was adjusted by gas wiping and measured by ICP (Inductively Coupled Plasma) emission spectroscopic analysis. The amount of galvanized adhesion was 31 to 73 g / m 2 per side.
上記の方法で製造した亜鉛めっき鋼板、および合金化亜鉛めっき鋼板を、５０ｍｍ×１５０ｍｍの大きさに切断し、真空スパッタ蒸着により、亜鉛めっき層上にＳｎ層を有するサンプルを作製した。このときのＳｎ付着量は、成膜時間で調整し、０．２１〜１０．９ｇ／ｍ2とした。比較例として、Ｓｎ層を形成しないサンプルも作製した。 The galvanized steel sheet manufactured by the above method and the alloyed galvanized steel sheet were cut into a size of 50 mm × 150 mm, and a sample having an Sn layer on the galvanized layer was produced by vacuum sputter deposition. The Sn adhesion amount at this time was adjusted by the film formation time, and was set to 0.21 to 10.9 g / m 2 . As a comparative example, a sample in which the Sn layer was not formed was also produced.
上記の方法で作製した各サンプルを、通電加熱方式で加熱した。加熱パターンは、室温から９００℃まで３０秒かけて加熱した後、Ｎ2ガスの吹き付けにより急速冷却することにより、熱間プレス成形を模擬した加熱処理とした。 Each sample produced by the above method was heated by an electric heating method. The heating pattern was a heat treatment simulating hot press forming by heating from room temperature to 900 ° C. over 30 seconds and then rapidly cooling by blowing N 2 gas.
（加熱後の二酸化スズの同定）
加熱処理後の上記サンプルにおける表面組成をＸ線回折で分析した。このとき用いたＸ線回折装置は、「Ｘ線回折装置 ＲＡＤ−ＲＵ３００」（商品名 理学電機社製）とし、線源はＣｏ−Ｋα線を用い、θ―２θ法により測定して、ＩＣＤＤ（Ｉｎｔｅｒ Ｃｅｎｔｒｅ ｆｏｒ Ｄｉｆｆｒａｃｔｉｏｎ Ｄａｔａ：国際回折データセンター）カードＮｏ．４１−１４４５と比較することによって、二酸化スズの有無を確認した。尚、この評価方法によれば、検出限界未満になると、二酸化スズが微量に存在していても、「二酸化スズは無し」と評価される。
(Identification of tin dioxide after heating)
The surface composition of the sample after the heat treatment was analyzed by X-ray diffraction. The X-ray diffractometer used at this time was an “X-ray diffractometer RAD-RU300” (trade name, manufactured by Rigaku Corporation), the source was a Co—Kα ray, measured by the θ-2θ method, and ICDD ( Inter Center for Diffraction Data: International Diffraction Data Center) Card No. The presence or absence of tin dioxide was confirmed by comparison with 41-1445. In addition, according to this evaluation method, when it becomes less than the detection limit, even if a small amount of tin dioxide exists, it is evaluated as “no tin dioxide”.
（塗膜密着性の評価）
加熱処理後の上記サンプルに対し、アルカリ脱脂洗浄、リン酸亜鉛処理をした後、電着塗装を行った。このときのリン酸亜鉛処理は、日本パーカライジング（株）製のパルボンドＬ３０６５（ＰＢＬ−Ｌ３０６５）を用い、２分間の浸漬により付着量を３ｇ／ｍ2前後に調整した。電着塗装は、日本ペイント（株）製のカチオン電着塗料（パワーニックスエクセル１２２０）を用いて電圧１７０Ｖにて塗装、１８０℃で１５分焼付けを行い、膜厚を１５μｍに調整した。
(Evaluation of coating film adhesion)
The sample after the heat treatment was subjected to alkaline degreasing washing and zinc phosphate treatment, followed by electrodeposition coating. At this time, the zinc phosphate treatment was performed using Palbond L3065 (PBL-L3065) manufactured by Nippon Parkerizing Co., Ltd., and the adhesion amount was adjusted to around 3 g / m 2 by immersion for 2 minutes. Electrodeposition coating was performed using a cationic electrodeposition paint (Powernicks Excel 1220) manufactured by Nippon Paint Co., Ltd. at a voltage of 170 V and baked at 180 ° C. for 15 minutes to adjust the film thickness to 15 μm.
以上のように作製したサンプルを、５質量％ＮａＣｌ水溶液に、５０℃で７００時間浸漬した。浸漬の際には、サンプルの端部はシールを行い、端部からの腐食や浸漬水の浸潤の効果が無視できるようにした。浸漬終了後、図１に示す評価対象について、セロハンテープによる塗膜剥離試験を行い、電着塗装が剥離した部分の面積率を測定した。評価対象の領域は、熱間プレス成形を模擬した上記加熱処理時において均熱が保たれているサンプル長手方向の中央１００ｍｍ部×幅方向４０ｍｍ部（評価面積：４０ｍｍ×１００ｍｍ＝４０００ｍｍ2）とした。評価面積に占める塗膜剥離面積率を画像処理によって評価し、５％以下を合格とした。 The sample produced as described above was immersed in a 5% by mass NaCl aqueous solution at 50 ° C. for 700 hours. At the time of immersion, the end of the sample was sealed so that the effects of corrosion from the end and infiltration of immersion water could be ignored. After completion of the immersion, the evaluation target shown in FIG. 1 was subjected to a coating film peeling test using a cellophane tape, and the area ratio of the portion where the electrodeposition coating was peeled was measured. The region to be evaluated was the central 100 mm portion in the longitudinal direction of the sample and the 40 mm portion in the width direction (evaluation area: 40 mm × 100 mm = 4000 mm 2 ) in which soaking was maintained during the heat treatment simulating hot press forming. . The coating film peeling area ratio occupying the evaluation area was evaluated by image processing, and 5% or less was accepted.
これらの結果を、亜鉛めっき付着量、合金化の有無およびＳｎ付着量等と共に、下記表２、３に示す。 These results are shown in Tables 2 and 3 below together with the amount of galvanized adhesion, the presence or absence of alloying, the amount of Sn adhesion, and the like.
この結果から、次のように考察できる。まず実験Ｎｏ．３〜５、８〜１０、１３〜１５、１８〜２０、２３〜２５、２８〜３０、３２〜３４、３６〜３８、４０〜４２、４４〜４６、４８〜５０、５２〜５４は、本発明で規定する要件を満足するものであり、鋼板の成分組成にかかわらず、いずれも良好な塗膜密着性が達成されていることが分かる。これらは、亜鉛系めっき層の上に適切な付着量のＳｎ層を有する鋼板を用いた例であり、加熱後の表面に二酸化スズが形成されることによって、亜鉛めっき層中の亜鉛の酸化が抑制され、良好な塗膜密着性が達成されていると考えられる。 From this result, it can be considered as follows. First, experiment no. 3-5, 8-10, 13-15, 18-20, 23-25, 28-30, 32-34, 36-38, 40-42, 44-46, 48-50, 52-54 It satisfies the requirements defined in the invention, and it can be seen that good coating film adhesion is achieved in all cases, regardless of the component composition of the steel sheet. These are examples using a steel sheet having an Sn layer with an appropriate amount of adhesion on a zinc-based plating layer, and the formation of tin dioxide on the surface after heating causes oxidation of zinc in the zinc plating layer. It is considered that good coating film adhesion is achieved.
これに対し、実験Ｎｏ．１、２、６、７、１１、１２、１６、１７、２１、２２、２６、２７、３１、３５、３９、４３、４７、５１は、本発明で規定する要件を満たしておらず、塗膜密着性が劣化している。 In contrast, Experiment No. 1, 2, 6, 7, 11, 12, 16, 17, 21, 22, 26, 27, 31, 35, 39, 43, 47, 51 do not meet the requirements defined in the present invention, and Film adhesion has deteriorated.
詳細には、実験Ｎｏ．１、６、１１、１６、２１、２６、３１、３５、３９、４３、４７、５１は、亜鉛系めっき層の上にＳｎ層を形成しなかった例であり、加熱後の表面に二酸化スズが形成されず、亜鉛めっき層中の亜鉛の酸化が抑制されず、塗膜密着性が劣化している。 Specifically, Experiment No. 1, 6, 11, 16, 21, 26, 31, 35, 39, 43, 47, 51 are examples in which the Sn layer was not formed on the zinc-based plating layer, and tin dioxide was formed on the surface after heating. Is not formed, oxidation of zinc in the galvanized layer is not suppressed, and coating film adhesion is deteriorated.
また実験Ｎｏ．２、７、１２、１７、２２、２７では、亜鉛系めっき層の上にＳｎ層を形成したが、Ｓｎ付着量が不足するため、加熱後の表面に十分な二酸化スズが形成されず、亜鉛めっき層中の亜鉛の酸化が抑制されず、塗膜密着性が劣化している。 In addition, Experiment No. In 2, 7, 12, 17, 22, and 27, the Sn layer was formed on the zinc-based plating layer. However, since the Sn adhesion amount was insufficient, sufficient tin dioxide was not formed on the surface after heating, and zinc was formed. Oxidation of zinc in the plating layer is not suppressed, and coating film adhesion is deteriorated.
Claims (8)
Ｃ ：０．１５〜０．４％、
Ｓｉ：０％超、３％以下、
Ｍｎ：０〜３％、
Ａｌ：０％超、０．１％以下、および
Ｂ ：０〜０．０１％
を含有し、残部が鉄および不可避不純物からなるものである請求項１〜３のいずれかに記載のプレス成形用表面処理鋼板。 The base steel plate has a chemical composition of mass%,
C: 0.15-0.4%,
Si: more than 0%, 3% or less,
Mn: 0 to 3%,
Al: more than 0%, 0.1% or less, and B: 0 to 0.01%
The surface-treated steel sheet for press forming according to any one of claims 1 to 3, wherein the balance is made of iron and inevitable impurities.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2015056364A JP2016176101A (en) | 2015-03-19 | 2015-03-19 | Surface treated steel sheet for press molding, and press molded article |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2015056364A JP2016176101A (en) | 2015-03-19 | 2015-03-19 | Surface treated steel sheet for press molding, and press molded article |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2016176101A true JP2016176101A (en) | 2016-10-06 |
Family
ID=57070325
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2015056364A Pending JP2016176101A (en) | 2015-03-19 | 2015-03-19 | Surface treated steel sheet for press molding, and press molded article |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2016176101A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20230183832A1 (en) * | 2020-02-28 | 2023-06-15 | Voestalpine Stahl Gmbh | Method for producing hardened steel components with a conditioned zinc alloy anti-corrosive layer |
Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5655590A (en) * | 1979-10-08 | 1981-05-16 | Nippon Steel Corp | Surface-treated steel sheet for easy open end |
| JPH03104882A (en) * | 1989-09-16 | 1991-05-01 | Nippon Steel Corp | Surface treated steel sheet for di can excellent in aptitude for printing substrate |
| JPH059781A (en) * | 1991-07-08 | 1993-01-19 | Nippon Steel Corp | Surface-treated steel sheet for container excellent in rust resistance and appearance |
| JPH0533188A (en) * | 1991-07-30 | 1993-02-09 | Nippon Steel Corp | Surface treated steel for vessel excellent in rust resistance and external appearance characteristic |
| JPH05214558A (en) * | 1991-12-10 | 1993-08-24 | Nkk Corp | Galvanized steel sheet excellent in press formability and spot weldability |
| JP2004124207A (en) * | 2002-10-04 | 2004-04-22 | Nippon Steel Corp | Zn-PLATED STEEL SHEET FOR HOT-PRESS, AND CAR COMPONENTS WITH HIGH STRENGTH USING IT |
| JP2004238733A (en) * | 2003-01-16 | 2004-08-26 | Nippon Steel Corp | Galvanized steel for laser welding, production method therefor, and laser welding method |
| JP2008184619A (en) * | 2007-01-26 | 2008-08-14 | Jfe Steel Kk | Galvannealed steel sheet |
| US20120328871A1 (en) * | 2010-02-19 | 2012-12-27 | Tapan Kumar Rout | Strip, Sheet or Blank Suitable for Hot Forming and Process for the Production Thereof |
| JP2013076139A (en) * | 2011-09-30 | 2013-04-25 | Nippon Steel & Sumitomo Metal Corp | High-strength hot-dip galvanized steel sheet superior in plating adhesion and formability, and method for manufacturing the same |
| WO2015001705A1 (en) * | 2013-07-02 | 2015-01-08 | Ｊｆｅスチール株式会社 | Method of manufacturing hot press member |
-
2015
- 2015-03-19 JP JP2015056364A patent/JP2016176101A/en active Pending
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5655590A (en) * | 1979-10-08 | 1981-05-16 | Nippon Steel Corp | Surface-treated steel sheet for easy open end |
| JPH03104882A (en) * | 1989-09-16 | 1991-05-01 | Nippon Steel Corp | Surface treated steel sheet for di can excellent in aptitude for printing substrate |
| JPH059781A (en) * | 1991-07-08 | 1993-01-19 | Nippon Steel Corp | Surface-treated steel sheet for container excellent in rust resistance and appearance |
| JPH0533188A (en) * | 1991-07-30 | 1993-02-09 | Nippon Steel Corp | Surface treated steel for vessel excellent in rust resistance and external appearance characteristic |
| JPH05214558A (en) * | 1991-12-10 | 1993-08-24 | Nkk Corp | Galvanized steel sheet excellent in press formability and spot weldability |
| JP2004124207A (en) * | 2002-10-04 | 2004-04-22 | Nippon Steel Corp | Zn-PLATED STEEL SHEET FOR HOT-PRESS, AND CAR COMPONENTS WITH HIGH STRENGTH USING IT |
| JP2004238733A (en) * | 2003-01-16 | 2004-08-26 | Nippon Steel Corp | Galvanized steel for laser welding, production method therefor, and laser welding method |
| JP2008184619A (en) * | 2007-01-26 | 2008-08-14 | Jfe Steel Kk | Galvannealed steel sheet |
| US20120328871A1 (en) * | 2010-02-19 | 2012-12-27 | Tapan Kumar Rout | Strip, Sheet or Blank Suitable for Hot Forming and Process for the Production Thereof |
| JP2013519793A (en) * | 2010-02-19 | 2013-05-30 | タタ、スティール、ネダーランド、テクノロジー、ベスローテン、フェンノートシャップ | Strips, sheets or blanks suitable for hot forming, and methods for their production |
| JP2013076139A (en) * | 2011-09-30 | 2013-04-25 | Nippon Steel & Sumitomo Metal Corp | High-strength hot-dip galvanized steel sheet superior in plating adhesion and formability, and method for manufacturing the same |
| WO2015001705A1 (en) * | 2013-07-02 | 2015-01-08 | Ｊｆｅスチール株式会社 | Method of manufacturing hot press member |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20230183832A1 (en) * | 2020-02-28 | 2023-06-15 | Voestalpine Stahl Gmbh | Method for producing hardened steel components with a conditioned zinc alloy anti-corrosive layer |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP6908659B2 (en) | Steel plate coated with an aluminum-based metal coating | |
| US7673485B2 (en) | Hot press forming method | |
| JP6836600B2 (en) | Hot stamping material | |
| JP6813133B2 (en) | Manufacturing method of aluminum-plated steel sheet, hot stamping member and hot stamping member | |
| CN108138282B (en) | Galvanized steel sheet for hot pressing and method for producing hot press-formed article | |
| JP6805044B2 (en) | Alloyed hot-dip galvanized steel sheet for hot stamping | |
| JP4671634B2 (en) | High-strength quenched molded body with excellent corrosion resistance and method for producing the same | |
| JP5853683B2 (en) | Method for producing cold-rolled steel sheet with excellent chemical conversion and post-coating corrosion resistance | |
| JP3758549B2 (en) | Hot pressing method | |
| JP4889212B2 (en) | High-strength galvannealed steel sheet and method for producing the same | |
| JP5637230B2 (en) | Manufacturing method of high-strength cold-rolled steel sheet | |
| JP3885763B2 (en) | Hot-dip galvanized steel sheet for quenching, its manufacturing method and use | |
| JP4331915B2 (en) | High strength and high ductility hot dip galvanized steel sheet excellent in fatigue durability and corrosion resistance and method for producing the same | |
| JP2018090879A (en) | Steel plate for hot press molding, method for producing hot press molding, and hot press molding | |
| KR101621630B1 (en) | Galvannealed steel sheet having high corrosion resistance after painting | |
| JP6414387B2 (en) | Manufacturing method of automobile parts | |
| JP7453583B2 (en) | Al-plated hot stamping steel material | |
| JP7215519B2 (en) | HOT PRESS MEMBER AND MANUFACTURING METHOD THEREOF | |
| TW202009315A (en) | Hot-dipped galvanized steel sheet and method of forming the same | |
| JP2014240510A (en) | Galvanized steel sheet and production method thereof | |
| JP2016176101A (en) | Surface treated steel sheet for press molding, and press molded article | |
| JP2020041177A (en) | Steel plate for hot pressing | |
| JP2020041174A (en) | Steel plate for hot pressing | |
| JP3875958B2 (en) | High strength and high ductility hot dip galvanized steel sheet with excellent workability and manufacturing method thereof | |
| JP6089895B2 (en) | Alloyed hot-dip galvanized steel sheet with excellent chipping resistance |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| RD02 | Notification of acceptance of power of attorney |
Free format text: JAPANESE INTERMEDIATE CODE: A7422 Effective date: 20170222 |
|
| RD04 | Notification of resignation of power of attorney |
Free format text: JAPANESE INTERMEDIATE CODE: A7424 Effective date: 20170322 |
|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20170901 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20180530 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20180605 |
|
| A601 | Written request for extension of time |
Free format text: JAPANESE INTERMEDIATE CODE: A601 Effective date: 20180730 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20181003 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20190305 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20190425 |
|
| A02 | Decision of refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A02 Effective date: 20190702 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20190911 |
|
| A911 | Transfer to examiner for re-examination before appeal (zenchi) |
Free format text: JAPANESE INTERMEDIATE CODE: A911 Effective date: 20190919 |
|
| A912 | Re-examination (zenchi) completed and case transferred to appeal board |
Free format text: JAPANESE INTERMEDIATE CODE: A912 Effective date: 20191108 |