201134954 六、發明說明： 【發明所屬之技術領域】 本發明係關於最適於作為A型液晶電視之背光機殼等作 成大型平板做之科構件老化狀成雜及形狀束結性 優異之冷軋鋼板及其製造方法。 【先前技術】 於薄型液晶TV和0A機器等，使用許多經由彎曲•突出 成形為主體的加工所成形的平板狀零件。因此，在製造該等 ν’件所用之構件（薄鋼板)時，為了橋正板的形狀並且消除屈 服點延伸度’在調質軋製中進行延伸率數％左右的輕軋縮。 但是’於調質軋製後經過時間，發生屈服點延伸纟的復活和 延性降低等’铺為所謂之應變老化的特性惡化。特別，近 年來，為減低成本，非常多的案例係將捲材輸出並於海外進 行加壓加工，因製造捲材至加壓加工為止耗費時間，無法迴 避變形老化。又，即使為國内，於捲材的流通過程亦耗費時 間，或者，捲材以庫存型式保存之情況等，鋼板亦發生應變 老化。如此，發生應變老化使鋼板特性惡化之情況，必須進 行加壓條件和金屬模具等的再調整，成為成本增加的要因之 ·— 〇 更且，最近，為了削減成本，大為期望減薄構件板厚並且 削減鋼板的使用量。若減薄板厚，則容易發生加工時之形狀 束結性惡化、於加工時發生裂開等問題。更且，為了彌補薄 100101211 3 201134954 身化所伴隨的構件剛性降低，有時亦追 工簟桩& 垾珠、經由彎曲加 寻镬近封閉剖面構造等變更零件形 # ^ 狀使加工條件變得愈 :厫可A果，助長加壓時的裂開和形狀不良。特別，於 彎曲加工之情況，發生稱為棱線彎曲 、 ^ 狀不良，並且產生 7件相相題。又，於突出加m兄，在突出高度大時 產生裂開，在抑制皺紋弱時產生皺紋等問題。 對於此種稜線-曲有利減低α。但是，r值降低導致延 伸度降低，對於突出加工有不利的作用。更H經由應變 老化引㈣㈣延伸度祕活和驗降低，則在變更加壓條 件等變成無法應付裂開和皺紋等。 應變老化已知係由鋼板中固熔的c和Ν所引起，添加Ti、 Nb等氮化物生成元素並將此C、N作為析出物而固定的正 鋼係難弓丨起應變老化的鋼板。但是，先前的IJ7鋼為製造 成本高，且Γ值高，不利於包含彎曲成形的情況。 由上述，對於老化後亦為低r值、屈服點延伸度小，並且 延伸度南之廉價構件（薄鋼板）的期望非常大。 乍為值低且形狀;束結性優異的鋼板，例如，於專利文獻 1中揭示在熱軋之精乳中，使〜(Ar3+l⑼)的乾縮率為 25/〇以上、軋製時的摩擦係數為〇 2以下，並在μ以上完 成精乳或者’在Ar3以下的軋縮率為25%以上、乾製時 的摩擦係數為G.2以下進行精軋，控制集合組織之同時，將 軋製方向或乾製垂直方向之『值中的至少一者設定成〇.7以 100101211 4 201134954 下的鋼板。 於專利文獻2中，揭示板面之平行{1〇〇}面與{1U}面之比 為1.0以上之形狀凍結性優異的汽車由肥粒鐵系薄鋼板。 於專利文獻3中’揭示為了取得形狀凍結性優異的肥粒鐵 系薄鋼板，控制{100}<011>〜{223}<110>方位群的強度和 {112}<11〇>、{554}<225>、{111}<112>、{ΐηρηο〉各方位 的強度；及將軋製方向之r值及軋製方向垂直之1*值中的至 少一者設定成0.7以下。 [先前技術文獻] [專利文獻] [專利文獻1]曰本專利第3532138號公報 [專利文獻2]日本專利特開2008-255491號公報 [專利文獻3]日本專利特開2003-55739號公報 【發明内容】 (發明所欲解決之問題） 但是’專利文獻1〜3中記載的鋼板，於老化後加工性降 低，並且發生加壓裂開等問題。 本發明係鑑於此類情事，以提供老化後之成形性及形狀凍 結性優異之冷軋鋼板及其製造方法為目的。 (解決問題之手段） 發明者等人為解決上述問題，重複致力研究調查。其結 果，發現將軋製方向、軋製45。方向，軋製垂直方向之平均 100101211 201134954 r值設定為1.2以下、老化後之延伸度設定為4〇%以上老 化後之屈服點延伸度設定為i.O%以下，則可取得即使老化 後成形性和形狀凍結性亦優異的冷軋鋼板。另外，此處，所 謂平均r值(rm)，係指軋製方向、軋製45。方向、軋製垂直 方向之r值分別设定為rL、r〇、rc時，rm二（Γ[ + + ^)/4。 又’根據本發明可確保老化後之成形性及形狀凍結性的機 制認為如下。一般而言，為消除屈服點延伸度，採用在室溫 下附加應變並導入可動轉位的方法。但是，應變量小的情 況，經由老化使可動轉位被C、N所固著，使屈服點延伸度 復活。另一方面，若加大室溫下的應變量，則由於屈服點變 大之同時延伸度降低，故成形性降低。於是，本發明中，著 眼於肥粒鐵粒徑的分佈。增大肥粒鐵粒徑的分佈下，即使應 變量少’亦可使應變的導入位置不均勻且使應變集中。其結 果’即使老化後亦可抑制屈服點延伸度的發生。又，導入應 變的少s午粒子，經由老化所造成的硬化亦少，故亦可抑制延 伸度降低，經由老化所造成的硬化亦少，故亦可抑制延伸度 降。因此，此種不均勻應變的導入，可達成加大肥粒鐵粒徑 分佈的標準偏差。 又’如上述之r值為1.2以下、老化後之延伸度為40%以 上、老化後之屈服點延伸度為1 〇Q/。以下的冷軋鋼板，於熱 軋中在肥粒鐵區域完成精軋並且以低溫捲取，在熱軋階段作 成未再結晶’於退火中控制熱履歷下，則可在控制肥粒鐵粒 100101211 6 201134954 徑和粒徑分佈之同時，控制冷卻後的應變量。 本發明係根據上述發現而完成者，其要旨如下。 [1] 一種老化後之成形性及形狀凍結性優異之冷札鋼板， 其特徵在於，依質量％計含有’ C : 0.01〜0.05%、u · U.U5% 以下、Μη : 0.1 〜0.5%、P : 0.05%以下、S : 〇.〇2〇/〇以下 ^ 0.02〜0.10%、Ν : 0.005%以下，其餘部分為鐵及不可避免的 雜質之組成和肥粒鐵相主體的組織，且，該肥粒鐵相的平均 粒徑為10〜20μιη，各個肥粒鐵粒徑除以平均值之值的自然 對數標準偏差設定為σΑ時，σΑ2 0.30。 [2] 如上述[1 ]之老化後之成性及形狀;東結性優異之冷札鋼 板’其中，依質量％計更進一步含有，Ti: 0.005〜0.020/ρβ : 0.0003〜0.0030%之任1種以上。 [3] 如上述[1 ]或[2]之老化後之成形性及形狀凍結性優異 之冷軋鋼板，其中，在鋼板表面具有鍍鋅系層。 [4] 一種老化後之成形性及形狀凍結性優異之冷軋鋼板的 製造方法，其特徵在於，將上述[1]或上述[2]中記載組成所 成的鋼胚，以精軋之最終出側溫度為（Ar3-100°C)〜Ar3°C、 捲取溫度以未滿550°C熱軋，接著，酸洗，並以40〜80%之 軋縮率進行冷軋後，進行退火時，將600°C至均熱溫度為止 之溫度域以1〜30°C/s之平均加熱速度加熱，上述均熱溫度 為800〜900°C、均熱時間為30〜200秒鐘予以均熱處理，並 將上述均熱溫度至55(TC為止之溫度域以3〜30°C/s之平均 100101211 7 201134954 冷卻速度冷卻’以500〜300°C保持30秒鐘以上，並於—、θ 加以延伸率：0.5〜2.0%的應變。 [5]如上述[4]之老化後之成形性及形狀凍結性優異之冷札 鋼板的製造方法’其中，上述均熱處理後，將上述均熱^度 至55〇°C為止之溫度域以3〜3(TC/S之平均冷卻速度冷句 著冷卻至50(TC以下之溫度域，其次再加熱至 溫度域，其後以50〇〜30(TC保持3〇秒鐘以上並於室加以 延伸率：0.5〜2.0%的應變。 另外，於本說明書中，顯示鋼成分的％全部為質量。/。。又， 本發明作為對象的冷軋鋼板，亦包含對冷軋鋼板施行鍍鋅系 處理（例如，電鍍鋅系處理、熔融鍍鋅系處理、合金化熔融 鍍鋅處理）的鋼板。更且，亦包含在其上經由化成處理等附 加皮臈的鋼板。 又，本發明之鋼板’可廣泛使用作為大型TV之背光機殼、 冰箱的面板和冷氣室外機等平面部和施行彎曲、突出、輕度 深拉伸加工等家電用途的一般構件。更且，若使用本發明， 例如了以板厚〇,8mm的鋼板，製造650x500mm左右（32V 型）以上的背光機殼。 [發明效果] 右根據本發明’則可取得老化後之成形性及形狀凍結性優 異的冷乾鋼板。藉此可確保大型零件所要求的平板形狀，可 製造大型液晶電視之背光機殼等構件。 100101211 8 201134954 【實施方式】 說明關於本發明之鋼板的化學成分。另外，於下列之說明 中，成分元素之含有量％全部意指質量〇/〇。 C : 0.01 〜0.05% c可形成碳化鐵(cementite)，減低固熔c，降低屈服強度。 若C少則抑制碳化鐵的生成，增加，變成易於老化 硬化之同時，於熱軋中，在完工台内由添斯田鐵變態成肥粒 鐵之情況，二相區域小，故應變阻力急劇降低，且軋製變成 不安定。因此，（：必須設定為〇.〇1〇/。以上。另一方面，若c 變多，則粒成長受到抑制而細粒化，故鋼板硬質化且延度降 低。因此’ C必須設定為〇 〇5〇/0以下。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cold-rolled steel sheet which is most suitable as a large-sized flat plate made of a backlight casing of an A-type liquid crystal television, and which has an aged shape and excellent shape bundleability. And its manufacturing method. [Prior Art] In a thin liquid crystal TV, an OA machine, or the like, a plurality of flat-shaped parts formed by bending and protruding forming as a main body are used. Therefore, in the case of manufacturing the members (thin steel sheets) for the members of the ν', the shape of the bridge is eliminated and the elongation at break is eliminated. In the temper rolling, a slight rolling reduction of about several percent is performed. However, the elapsed time after quenching and tempering, the revival of the yield point extension 降低 and the decrease in ductility are the deterioration of the so-called strain aging characteristics. In particular, in recent years, in order to reduce costs, a large number of cases have been used to output coils and pressurize them overseas. It takes time to manufacture coils to pressurization, and it is impossible to avoid deformation aging. Further, even in China, the steel sheet is also strain-aged because it takes time to circulate the coil material, or when the coil material is stored in an inventory type. In this way, when strain aging deteriorates the characteristics of the steel sheet, it is necessary to re-adjust the pressurization conditions and the metal mold, etc., which is a factor of cost increase. Recently, in order to reduce the cost, it is highly desirable to thin the member sheet. It is thick and cuts the amount of steel plate used. When the thickness is reduced, problems such as deterioration of the shape at the time of processing and cracking during processing tend to occur. In addition, in order to compensate for the decrease in the rigidity of the member accompanying the thin body of 100101211 3 201134954, it is sometimes necessary to change the shape of the part by changing the shape of the part by the bending of the pile and the bead. Get more: You can use A fruit to promote cracking and poor shape during pressurization. In particular, in the case of bending, a phenomenon called ridge bending, a poor shape, and seven phase problems are generated. Further, in the case of highlighting the m brother, cracking occurs when the protruding height is large, and wrinkles are generated when the wrinkles are suppressed from being weak. For such ridge-curvature, it is advantageous to reduce α. However, a decrease in the value of r results in a decrease in elongation, which is disadvantageous for the outstanding processing. Further, H is strained and aged (4) and (4). If the elongation is reduced and the pressure is reduced, it is impossible to cope with cracking and wrinkles. The strain aging is known to be caused by the solid solution of c and yttrium in the steel sheet, and the addition of a nitride-forming element such as Ti or Nb and the fixation of the C and N as precipitates is difficult to bow the strain-aged steel sheet. However, the prior IJ7 steel is expensive to manufacture and has a high devaluation, which is not conducive to the case of including bending. From the above, it is expected that the low-value r value after the aging, the yield point elongation is small, and the low-cost member (thin steel sheet) of the south extension is very large.钢板 is a steel sheet having a low value and a shape, and is excellent in the bundleability. For example, Patent Document 1 discloses that in the hot-rolled fine emulsion, the dry shrinkage ratio of 〜(Ar3+l(9)) is 25/〇 or more, and rolling is performed. The friction coefficient is 〇2 or less, and the fineness is completed in μ or more, or the rolling reduction ratio of 25% or less under Ar3 and the friction coefficient at the time of drying are G.2 or less, and the assembly is controlled. At least one of the values of the rolling direction or the dry vertical direction is set to 钢板.7 to the steel plate under 100101211 4 201134954. In Patent Document 2, it is disclosed that an automobile having an excellent shape freezeability of a parallel {1〇〇} plane and a {1U} plane of a plate surface of 1.0 or more is made of a ferrite-based iron-based steel sheet. In Patent Document 3, it is disclosed that the strength of the {100}<011>~{223}<110> orientation group is controlled to obtain a ferrite-based iron-based steel sheet excellent in shape freezeability, and {112}<11〇>;,{554}<225>,{111}<112>, {ΐηρηο> intensity of each of the positions; and setting at least one of the r value of the rolling direction and the 1* value perpendicular to the rolling direction 0.7 or less. [PRIOR ART DOCUMENT] [Patent Document 1] Japanese Patent Laid-Open No. Hei. No. Hei. No. Hei. No. 2003-25539. DISCLOSURE OF THE INVENTION PROBLEMS TO BE SOLVED BY THE INVENTION However, in the steel sheets described in Patent Documents 1 to 3, workability after aging is lowered, and problems such as pressure cracking occur. In view of such circumstances, the present invention has an object of providing a cold-rolled steel sheet excellent in formability and shape freezeability after aging and a method for producing the same. (Means for Solving the Problem) The inventors and others have repeatedly worked hard to investigate and solve the above problems. As a result, it was found that the rolling direction was 45 and the rolling was performed. The direction, the average of the vertical direction of the rolling 100101211 201134954 r value is set to 1.2 or less, the elongation after aging is set to 4% or more, and the yield point elongation after aging is set to iO% or less, so that the formability even after aging can be obtained. A cold-rolled steel sheet excellent in shape freezeability. Here, the average r value (rm) here means the rolling direction and the rolling 45. When the r values of the direction and the rolling vertical direction are set to rL, r〇, and rc, respectively, rm is two (Γ[ + + ^)/4. Further, the mechanism for ensuring moldability and shape freezeability after aging according to the present invention is considered as follows. In general, in order to eliminate the yield point elongation, a method of adding strain at room temperature and introducing a movable index is employed. However, in the case where the strain is small, the movable index is fixed by C and N through aging, and the yield point elongation is revived. On the other hand, if the amount of strain at room temperature is increased, the yield is lowered because the yield point is increased and the elongation is lowered. Thus, in the present invention, attention is paid to the distribution of the particle size of the ferrite. When the distribution of the particle size of the ferrite iron is increased, even if the strain is small, the introduction position of the strain can be made uneven and the strain can be concentrated. As a result, the occurrence of yield point elongation can be suppressed even after aging. Further, since the introduction of the lesser s-day particles is less, the hardening by aging is also small, so that the decrease in the elongation can be suppressed, and the hardening by aging is also small, so that the elongation can be suppressed. Therefore, the introduction of such uneven strain can achieve a standard deviation of increasing the particle size distribution of the ferrite. Further, the above-mentioned r value is 1.2 or less, the elongation after aging is 40% or more, and the yield point elongation after aging is 1 〇Q/. The following cold-rolled steel sheet is subjected to finish rolling in the ferrite-rich iron region during hot rolling and coiled at a low temperature, and is not recrystallized in the hot rolling stage. Under the control of the heat history in the annealing, the ferrite iron particles 100100211 can be controlled. 6 201134954 While controlling the diameter and particle size distribution, control the strain after cooling. The present invention has been completed based on the above findings, and the gist thereof is as follows. [1] A cold-drawn steel sheet excellent in formability and shape-freezing property after aging, which is characterized by containing 'C: 0.01 to 0.05%, u · U.U5% or less, and Μη: 0.1 to 0.5% by mass%. , P : 0.05% or less, S: 〇.〇2〇/〇 below ^ 0.02~0.10%, Ν: 0.005% or less, the rest is the composition of iron and unavoidable impurities and the structure of the iron phase of the fat grain, and The average particle diameter of the ferrite iron phase is 10 to 20 μm, and the natural logarithmic standard deviation of the particle diameter of each fertilized iron divided by the average value is set to σΑ, σΑ2 0.30. [2] The aging and shape after aging as described above [1]; the cold-stained steel sheet excellent in east knotability, which is further contained by mass%, Ti: 0.005 to 0.020/ρβ: 0.0003 to 0.0030% More than one type. [3] The cold-rolled steel sheet having excellent formability and shape-freezing property after aging as described in [1] or [2] above, wherein the steel sheet has a galvanized layer on the surface thereof. [4] A method for producing a cold-rolled steel sheet having excellent formability and shape-freezing property after aging, characterized in that the steel preform formed by the composition described in the above [1] or [2] is finally finished. The exit side temperature is (Ar3-100 ° C) to Ar 3 ° C, the coiling temperature is hot rolled at less than 550 ° C, followed by pickling, and cold rolling is performed at a shrinkage ratio of 40 to 80%, followed by annealing. When the temperature range from 600 ° C to the soaking temperature is heated at an average heating rate of 1 to 30 ° C / s, the soaking temperature is 800 to 900 ° C, and the soaking time is 30 to 200 seconds. Heat treatment, and the above soaking temperature to 55 (the temperature range until TC is cooled at an average of 100 to 30 ° C / s of 100 to 30 ° C / s) at a cooling rate of 500 to 300 ° C for more than 30 seconds, and at -, θ The elongation is 0.5 to 2.0% of the strain. [5] The method for producing a cold-slab steel sheet having excellent moldability and shape-freezing property after aging as described in the above [4], wherein the soaking heat is performed after the soaking treatment. The temperature range up to 55 ° ° C is 3 to 3 (the average cooling rate of TC / S is cooled to 50 (the temperature range below TC, followed by the addition To the temperature range, thereafter, 50 〇 to 30 (TC held for 3 sec seconds and the elongation in the chamber: 0.5 to 2.0% strain. In addition, in this specification, it is shown that all of the steel components are mass. Further, the cold-rolled steel sheet to which the present invention is applied also includes a steel sheet which is subjected to a galvanizing treatment (for example, an electrogalvanizing treatment, a hot-dip galvanizing treatment, or an alloyed hot-dip galvanizing treatment) on a cold-rolled steel sheet. In addition, the steel sheet of the present invention can be widely used as a flat casing of a large TV, a panel of a refrigerator, a flat portion of a cold air outdoor unit, and the like, and is bent, protruded, and the like. In the case of using the present invention, for example, a backlight case having a thickness of about 650 x 500 mm (32 V type) or more is produced by using a steel plate having a thickness of 8 mm. [Effect of the invention] Right According to the present invention, it is possible to obtain a cold-drying steel sheet excellent in moldability and shape freezeability after aging, thereby securing a flat plate shape required for a large-sized component, and manufacturing a backlight casing of a large-sized liquid crystal television. 100101211 8 201134954 [Embodiment] The chemical composition of the steel sheet according to the present invention will be described. In the following description, the content % of the component elements all means mass 〇 / 〇. C : 0.01 〜 0.05% c can form carbonization Iron (cementite), reduce solid solution c, reduce yield strength. If C is less, it will inhibit the formation of iron carbide, increase it, and become easy to age harden. In hot rolling, it will be metamorphosed into fertilizer in the finishing station. In the case of granular iron, the two-phase region is small, so the strain resistance is drastically lowered, and the rolling becomes unstable. Therefore, (: must be set to 〇.〇1〇/. Above. On the other hand, if c is increased, the grain growth is suppressed and the grain is finely granulated, so the steel plate is hardened and the ductility is lowered. Therefore, 'C must be set to 〇〇5〇/0 or less.
Si : 0.05%以下 若大量添加Si，則經由硬質化使成形性惡化，經由退火 時生成的Si氧化物’使鍛敷性受到阻礙。因此，y必須設 定為0.05%以下。 Μη ： 0.1^0.5% Μη係將有害之鋼中S以MnS型式無害化，故必須設定為 0_1%以上。另一方面，大量的Μη經由強化固熔和生成低溫 變態相造成硬質化，使成形性惡化。又，Μη使變態點降低， 且於熱軋中難在肥粒鐵區域軋製。更且，退火時，抑制肥粒 鐵的再結晶使組織細粒化。因此，Μη必須設定為〇 5〇/〇以 下，較隹為0.3%以下。 100101211 9 201134954 P : 0.05%以下 P在粒界偏析’使延性和靭性惡化，故必須設定為〇 〇 以下。較佳為0.03%以下。 S : 0.02%以下 S顯著降低加熱中的延性，誘發熱裂開，使表面性狀顯著 惡化。更且，S不僅幾乎無助於強度，或者經由形成粗大: MnS作為雜質元素，使延性降低。該等問題係 &里超過 0.0 2 %變得顯著’期望極力減低。因此，S量必須設定為〇 〇 2 〇/ 以下。 A1 ： 0.02-0.10% A1係將N作為氮化物而固定，可抑制固炫n造成老化硬 化。為了獲得此種效果，必須將A1設定為0.02%以上。另 一方面，添加大量A1，不僅使強度上升且成形性降低，並 且伴隨成本上升。因此，A1必須設定為〇. 10%以下。 N : 0,005%以下 若含有大量N，則熱軋中伴隨鋼胚裂開，有發生表面瑕疵_ 之虞。又，於冷軋、退火後以固熔N型式存在之情況，引 起老化硬化。因此，N必須設定為0.005%以下。 上述元素以外，本發明中，以改善老化性和形狀康結性為 目的，可在Ti : 0.005〜0.02%、B : 0.0003〜0 0030%之範圍内 含有Ti、B中之1種以上。Si: 0.05% or less When Si is added in a large amount, the moldability is deteriorated by hardening, and the forgeability is inhibited by the Si oxide produced during annealing. Therefore, y must be set to 0.05% or less. Μη : 0.1^0.5% Μη In the harmful steel, S is harmless in the MnS type, so it must be set to 0_1% or more. On the other hand, a large amount of Μη is hardened by strengthening solid solution and generating a low-temperature metamorphic phase, and the formability is deteriorated. Further, Μη lowers the metamorphic point and is difficult to roll in the ferrite iron region during hot rolling. Further, at the time of annealing, recrystallization of the ferrite iron is inhibited to coarsen the structure. Therefore, Μη must be set to 〇 5〇/〇, which is less than 0.3%. 100101211 9 201134954 P : 0.05% or less P segregation at the grain boundary' deteriorates ductility and toughness, so it must be set to 〇 〇 or less. It is preferably 0.03% or less. S : 0.02% or less S significantly reduces ductility during heating, induces thermal cracking, and significantly deteriorates surface properties. Furthermore, S not only contributes little to strength, but also reduces ductility by forming coarse: MnS as an impurity element. These problems are more than 0.0 2% in && significant expectations. Therefore, the S amount must be set to 〇 〇 2 〇 / below. A1 : 0.02-0.10% A1 is fixed by using N as a nitride, which suppresses aging and hardening. In order to obtain such an effect, A1 must be set to 0.02% or more. On the other hand, the addition of a large amount of A1 not only increases the strength but also lowers the formability and increases the cost. Therefore, A1 must be set to 〇. 10% or less. N: 0,005% or less If a large amount of N is contained, the steel sheet is cracked in the hot rolling, and surface 瑕疵 occurs. Further, in the case of the presence of a solid-melting N type after cold rolling and annealing, aging hardening is caused. Therefore, N must be set to 0.005% or less. In the present invention, in the present invention, one or more of Ti and B may be contained in the range of Ti: 0.005 to 0.02% and B: 0.0003 to 0030% for the purpose of improving the aging property and the shape retention property.
Ti : 0.005〜0.02% 100101211 10 201134954Ti : 0.005~0.02% 100101211 10 201134954
Ti在高溫與N結合形成氮化物，減少固熔N可改善老化 性。為了獲得此種效果，Ti必須設定為0.005%以上。另一 方面，若Ti的含有量多，則進一步與C結合生成碳化物和 碳氮化物，故強度上升，成形性降低。因此，含有Ti之情 況設定為0.005%以上且0.02%以下。 B : 0.0003〜0.0030% B在高溫與N結合形成氮化物，減少固熔N可改善老化 性。更且’ B在冷軋後的退火過程可抑制肥粒鐵的粒成長， 且可抑制r值改善形狀凍結性。為了獲得此種效果，b必須 δ又疋為0.0003%以上。另一方面，於B大量存在之情況，由 於抑制退火時之肥粒鐵的再結晶，故組織細粒化。因此，含 有Β之情況下設定為0 0003%以上且〇 0030%以下。 上述以外之成分係由鐵及不可避免的雜質所構成。作為不 可避免的雜質’可列舉例如易由廢鐵中混之〇 〇5%以下的 Cu、Cr ;和其他 0.01%以下的 Sn、M〇、W、V、Nb、Ni 等。 本發明之鋼板組織，作成肥粒鐵相主體。又，肥粒鐵相的 平均粒徑為10〜2〇μιη。更且，各個肥粒鐵粒徑除以平均值 之值的自然對數標準偏差設定為〜時，〜2〇.3〇。 「為了確保成形性，將軟質的肥粒鐵相作為主體。此處所謂 /鐵相作為主體」，係指肥粒鐵相相對於組織全體之比 例以面積率為95%以上之情況。以肥粒鐵組織作為主體，可 達成老化後之延伸度4G%以上。若肥粒鐵組織為⑽％則延 100101211 201134954 伸度提高故為佳。作為主相以外之第二相為碳化鐵相和波來 鐵相等’面積率可含有5%以下之範圍。若變多超過抓， 則延性的降低顯著。另外，肥粒鐵相的面積率可根據觀 織，辨別肥粒鐵相與其料之相，並且㈣影像處理則可求 出。 平均粒徑’為了確保成形性，設定為ΙΟμηι以上。另一方 面，若粒㈣大’則除了成形時發鎌皮料觀不良以外， 由於粒徑分佈變小，故平均粒徑的上限設定為2〇叫^。另外， 平均粒徑可根據切斷法測定，由軋製方向與板厚方向之平均 切片長度L卜Lc，以2/[(1/L1) + (1/Lc)]算出。 本發明係加大肥粒鐵粒徑的分佈下，即使應變量少，亦可 使應變導入位置不均勻且使應變集中，於老化後亦可抑制屈 服點延伸度的發生。又，導入應變少的粒子，因在老化造成 的硬化亦少’故亦可抑制延伸度的降低。因此，各個肥粒鐵 粒徑除以平均值之值的自然對數標準偏差設定為口八時，必 須為σΑ20.30。以下，將其說明。 若考慮實際的鋼板使用，若認為室溫(2〇。〇下的老化期間 為6個月即為充分。圖1表示於20°C老化6個月時之0八 對於屈服延伸度(YP-E1)與延伸度(E1)的影響圖。又，圖i 係使用具有 C : 0·01 〜0.05%、Si: 0.05%以下、Μη : 〇]〜〇 5%、 Ρ : 0.05%以下、S : 0.02%以下、A1: 0 02〜0.10〇/〇、ν : 〇 005% 以下，其餘部分為鐵及不玎避免的雜質之組成，且肥粒鐵相 100101211 201134954 之比例以面積率為95°/°以上，且，肥粒鐵相之平均极彳為 10〜20μιη的各種鋼板’並將該等鋼板加工成JIS 5號抵伸★式 驗片進行測定者。此處’將老化後之屈服延伸度設定為1 〇% 以下，可將成型後的皺紋抑制至無或者幾乎無法以目視判斷 之程度。又，將老化後之延伸度設定為4〇%以上，則突出成 型時的壁角可以成型至不會裂開45°左右，幾乎可對應全部 的加壓成形。如圖1所示般，將σΑ設定為0.30以上，則屈 服延伸度可小至1.0%以下之同時，延伸度可大至40%以 上。因此，將σΑ設定為0.30以上。 其次說明關於本發明之鋼板的製造條件。於本發明中，將 具有上述組成之鋼胚，以精軋之最終出側溫度為（Ar3_100 °C)〜Ar3°C、捲取溫度以未滿550°C熱軋，接著，酸洗，並 以40〜80%之軋縮率進行冷軋後，進行退火時，將6〇〇。〇至 均熱溫度為止之溫度域以1〜3〇°C/s之平均加熱速度加熱， 且均熱溫度為800〜900°C、均熱時間為30〜200秒鐘予以均 熱處理，並將上述均熱溫度至55(TC為止之溫度域以3〜3〇 °C/s之平均冷卻速度冷卻，以500〜30CTC保持30秒鐘以上， 並於室溫加以0.5〜2.0%的應變，則可加大肥粒鐵粒徑的分 佈’取得老化後之低屈服點強度和低r值以及優異的延伸 度。 精軋完成溫度：（Ar3-l〇(TC)〜Ar3 將熱軋中的精軋於肥粒鐵區域完成’則可在肥粒鐵組織蓄 100101211 13 201134954 積應變之同時，可根據結晶方位不均勻進行恢復。其結果， 應變的蓄積變得不均勻’可加大退火後之肥粒鐵的粒徑分 佈。又，根據結晶方位的不均勻使集合組織的發達無規則 化，可減低r值’並且提高形狀凍結性。因此，精軋的最終 溫度必須設定為Ar3以下。更佳為未滿Ar3的溫度。於Ar3 以下的軋縮量並無特別規定’但較佳為10%以上、更佳為 20%以上。另一方面，若精軋完成溫度變低，則導入應變的 結晶不會進行恢復，應變的蓄積不可能為不均勻。更且，軋 製荷重變大，造成作業上之困難，因此，精軋完成溫度必須 設定為（Ar3-100°C)以上。 另外，Ar3可依下式求出。Ti combines with N to form a nitride at a high temperature, and the reduction of solid solution N improves aging. In order to obtain such an effect, Ti must be set to 0.005% or more. On the other hand, when the content of Ti is large, carbides and carbonitrides are formed in combination with C, so that the strength is increased and the formability is lowered. Therefore, the case of containing Ti is set to be 0.005% or more and 0.02% or less. B : 0.0003 to 0.0030% B combines with N to form a nitride at a high temperature, and the reduction of solid solution N improves aging. Further, the annealing process of the B after the cold rolling can suppress the grain growth of the ferrite iron, and can suppress the r value to improve the shape freezing property. In order to obtain such an effect, b must have a δ of 0.0003% or more. On the other hand, in the case where B is present in a large amount, the structure is finely granulated because the recrystallization of the ferrite iron during annealing is suppressed. Therefore, in the case of enthalpy, it is set to 0. 0003% or more and 〇 0030% or less. The components other than the above are composed of iron and unavoidable impurities. Examples of the unavoidable impurities include, for example, Cu and Cr which are easily mixed with 5% by weight of scrap iron, and Sn, M〇, W, V, Nb, Ni, and the like which are 0.01% or less. The steel sheet structure of the present invention is formed into a ferrite-rich iron phase body. Further, the average particle diameter of the ferrite iron phase is 10 to 2 〇 μιη. Further, the natural logarithmic standard deviation of the values of the particle diameters of the respective ferrite grains divided by the average value is set to 〜2〇.3〇. "In order to ensure the formability, the soft ferrite phase is the main component. Here, the "iron phase as the main component" means that the ratio of the ferrite phase to the entire structure is 95% or more. With the ferrite iron structure as the main body, the elongation after aging can reach 4G% or more. If the ferrite grain iron structure is (10)%, it is better to extend 100101211 201134954. The second phase other than the main phase is equal to the iron carbide phase and the ferritic phase. The area ratio may be in the range of 5% or less. If it exceeds the catch, the decrease in ductility is significant. In addition, the area ratio of the ferrite grain iron phase can be determined according to the observation, and the phase of the ferrite grain iron phase and its material can be identified, and (4) image processing can be found. The average particle diameter ' is set to ΙΟμηι or more in order to ensure moldability. On the other hand, if the particle size (4) is large, the upper limit of the average particle diameter is set to 2 ^? Further, the average particle diameter can be measured by the cutting method, and the average slice length Lb Lc in the rolling direction and the thickness direction is calculated by 2/[(1/L1) + (1/Lc)]. According to the present invention, even if the strain amount is small, the strain introduction position is uneven and the strain is concentrated, and the elongation of the yield point can be suppressed after the aging. Further, since the particles having less strain are introduced, the hardening due to aging is also small, so that the decrease in elongation can be suppressed. Therefore, the natural logarithmic standard deviation of the particle size of each fertilized iron divided by the average value is set to 八Α, which must be σΑ20.30. Hereinafter, it will be explained. Considering the actual steel plate use, if room temperature is considered (2 〇. The aging period under 〇 is 6 months is sufficient. Figure 1 shows the 8% elongation at 20 ° C for yield elongation (YP- E1) and the influence diagram of the elongation (E1). In addition, the figure i is used with C: 0·01 ～0.05%, Si: 0.05% or less, Μη: 〇]~〇5%, Ρ: 0.05% or less, S : 0.02% or less, A1: 0 02~0.10〇/〇, ν: 〇005% or less, the rest is composed of iron and impurities that are not avoided, and the proportion of the ferrite grain iron phase 100101211 201134954 is 95°. /° or more, and the average iron of the ferrite-grained iron phase is 10 to 20 μm of various steel sheets' and these steel sheets are processed into JIS No. 5 proofing type test pieces for measurement. Here, 'the aging will be yielded. When the elongation is set to 1% or less, the wrinkles after molding can be suppressed to the extent that they are not or can hardly be visually judged. Further, when the elongation after aging is set to 4% or more, the corner angle at the time of protrusion molding can be It can be molded so as not to crack about 45°, and can be almost all pressed. For example, as shown in Fig. 1, σΑ is set to 0.30. The yield elongation can be as small as 1.0% or less, and the elongation can be as large as 40% or more. Therefore, σ Α is set to 0.30 or more. Next, the manufacturing conditions of the steel sheet according to the present invention will be described. In the present invention, The steel preform of the above composition is hot rolled at a final exit side temperature of the finish rolling (Ar3_100 ° C) to Ar 3 ° C, a coiling temperature of less than 550 ° C, followed by pickling, and rolling at 40 to 80%. After cold rolling, after annealing, the temperature range of 6 〇〇. 〇 to the soaking temperature is heated at an average heating rate of 1 to 3 〇 ° C / s, and the soaking temperature is 800 to 900 ° C. The soaking time is 30 to 200 seconds for soaking, and the soaking temperature is up to 55 (the temperature range until TC is cooled at an average cooling rate of 3 to 3 ° C / s, and kept at 500 to 30 CTC for 30 seconds. Above the clock, and adding 0.5~2.0% strain at room temperature, the distribution of the ferrite iron particle size can be increased to obtain the low yield point strength and low r value after aging and excellent elongation. Finish rolling finish temperature: (Ar3-l〇(TC)~Ar3 completes the finish rolling in the hot rolling in the ferrite iron area', then it can be stored in the ferrite iron structure. 101211 13 201134954 At the same time, the strain can be recovered according to the uneven orientation of the crystal. As a result, the accumulation of strain becomes uneven, which can increase the particle size distribution of the ferrite iron after annealing. The development of the assembly organization is irregular, which can reduce the r value and improve the shape freeze. Therefore, the final temperature of the finish rolling must be set to be less than Ar3, more preferably less than Ar3. The amount of shrinkage below Ar3 is There is no special regulation 'but preferably 10% or more, more preferably 20% or more. On the other hand, if the finish rolling completion temperature is lowered, the strain-introduced crystals are not recovered, and the accumulation of strain is unlikely to be uneven. Further, since the rolling load becomes large and the work is difficult, the finish rolling completion temperature must be set to (Ar3 - 100 ° C) or more. Further, Ar3 can be obtained by the following formula.
Μη含有量<0.4%之情況：Ar3 = 880-l〇〇〇xC含有量（〇/〇) Μη含有篁2 0.4 /ί>之情況· Ar3 = 870-1 〇〇〇xC含有量（y) 捲取溫度：未滿550°C 若精軋後的捲取溫度高，則肥粒鐵再結晶，無法導入不均 勻的應變，故捲取溫度必須設定為未滿55〇°c。捲取⑺户、 下限並無特別限定’但若溫度過低’則捲材的振 / 、 鄉取形狀轡 差，故以300 C以上為佳。精軋完成至捲取為止的a浴、 並無特別限定，但以10°C/s以上為佳，更佳為3〇c>C/ P速度 再佳為100°C/s以上。 以上’ 冷軋時的軋縮率：40〜80% 將熱軋板酸洗後之冷軋中的軋縮率大的情況 又'楚導 100101211 14 201134954 均勻化’在退火後之肥粒鐵粒徑分佈變小之同時，因應變量 增大而細粒化且高強度化，且形成性降低。又，集合組織亦 發達，r值變高且形狀凍結性降低。由上述，軋縮率必須設 定為80%以下。另一方面，軋縮率小之情況，所導入的應變 量少，使退火時的再結晶被抑制，成為恢復組織，成形性降 低。因此，軋縮率必須設定為40%以上。 600°C至均熱溫度為止之溫度域為止的平均加熱速度· 1 〜30〇C/s 進行冷軋後，進行退火。於本發明中，於退火中控制熱履 歷下，在控制肥粒鐵粒徑和粒徑分佈之同時，控制冷卻後的 應變量。因此進行退火時的製造條件係為重要的要件。 若600 C至均熱溫度為止的平均加熱速度小，則進行恢 復，使再結晶受到抑制。因此，平均加熱速度必須設定為 1 C/s以上。另一方面，若平均加熱速度大，則在加熱途中 使再結晶的核發生受到抑制，並在均熱時一併發生核，故粒 子細粒化，因此，平均加熱速度必須設定為3(TC/s以下。 均熱溫度：800〜900 C、均熱時間：3〇〜200秒鐘 加熱後之均熱處理，必須使再結晶完成之同時，加大粒徑 且提高成形性。因此，均熱溫度必須設定為800°C以上。另 一方面，若均熱温度過高，則由肥粒鐵進行至沃斯田鐵的變 態，以冷卻後的逆變態下使粒徑變小。因此，均熱溫度必須 設定為900°C以上。 100101211 15 201134954 又，右均熱時間短，目丨丨sB上 】再、，·〇日日未完成，或者，即使完成亦 因粒成長的時間短，鈐4 i1 又細粒化且成形性降低。因此，加熱時 的均熱時間必須設定Λ π本丨你 ^ 马3〇秒鐘以上。另一方面，若均熱時 間變長，則大的粒子一 瓊钕蝕小的粒子並且一邊成長變大， 故肥粒鐵粒徑的分佈蠻 ι小之同時’粒徑變大，於加壓成形時 造成橙皮等外觀不良。因士仏丸士 α 、囚此’均熱時間必須設定為200秒鐘 以下。 由均熱溫度至5耽為止之溫度域的平均冷卻速度 :3〜30〇C/s 右句,，、、處理後的冷郃速度小，則促進肥粒鐵粒的成長，大 的本子邊k姓小的粒子並且_邊成長變大，故肥粒鐵粒徑 的刀佈1 h之同時，粒徑變大，於加壓成形時，造成橙皮等 外觀不良目此’由均熱溫度至55〇。(：為止之溫度域的平均 冷卻速度必須設定為3t：/s以上。另_方面，若冷卻速度過 大’則強度變高_£成形性降低’故平均冷卻速度必須設定為 30°C/s 以下。 另外，由上述均熱至550°c為止之冷卻後，500〜300¾為 止的保持之間，若配合製造設備適當冷卻即可。較佳，由岣 熱溫度至550 C為止之冷却後’接著以同樣的冷卻速度範園 冷卻，即，以3〜3(Tc/s冷卻。 以500〜3⑼。C之保持時間：30秒鐘以上 固熔C，以碳化_型式析出，可提高老化性。因此，必須 於易析出碳化鐵之300〜5〇〇 C溫度域保持3〇秒鐘以上。時 100101211 16 201134954 間的上限並無特別規定，但因長時間保持使生產效率降低， 故保持時間的上限設定為300秒鐘左右為佳。 另外’保持後冷卻至室溫，上料卻條件並不必要特別規 定，若配合製造設備適當進行即可。 以室溫賦予應變、延伸率：〇 5〜2 〇% 退火後，在至溫附加應變，可消除屈服點。因此，於室温 加入的應變以延伸率必須設定為0.5%以上。另-方面，若 延伸率變大’則屈服點上升，成形性降低，故必須設定為 2.0%以下。較佳為u%以下。另外，以室溫賦予應變，係 可經由^予以乳製且亦可拉伸，或者，將報與拉伸予以組合 亦無妨。又’於軋製中，即使未潤滑亦可。 λ知本發明時’溶製方法可適當應用通常的轉爐法、電爐 法等。所熔製之鋼’轉造成鋼胚後，直接，或者冷卻並加熱， 施行熱軋。熱軋中以上述的加工條件予以加工後，以上述之 捲取溫度料捲取。接著，於—般的酸洗後，施行上述的冷 乾。關於冷軋後的退域理，以上述條件進行加熱 、保持、 冷卻。視需要’於480。(：附近以炼融鋅進行鍍敷^又，鍍敷 後，以500°C以上再加熱將鍍敷合金化亦可。另外，進行再 加熱時，必須於肥粒鐵不會粒成長的5耽以下。又，關於 上述之5GG〜3GG°C的保持’經由在冒c以上的再加熱使碳 化鐵有熔解的可能性，故在5()(rca上且5筑以下再加熱 之情況，再加熱後之500〜30(TC的保持時間設定為3〇秒鐘Μη content <0.4% of cases: Ar3 = 880-l〇〇〇xC content (〇/〇) Μη contains 篁2 0.4 /ί> cases · Ar3 = 870-1 〇〇〇xC content (y Coiling temperature: less than 550 °C If the coiling temperature after finish rolling is high, the ferrite iron recrystallizes and cannot introduce uneven strain, so the coiling temperature must be set to less than 55 °C. The winding (7) household and the lower limit are not particularly limited. However, if the temperature is too low, the vibration/resistance of the coil is inferior, so it is preferably 300 C or more. The a bath until the completion of the finish rolling is not particularly limited, but is preferably 10 ° C / s or more, more preferably 3 〇 c > C / P speed is more preferably 100 ° C / s or more. The above's rolling reduction ratio during cold rolling: 40 to 80%. The rolling reduction ratio in the cold rolling after pickling of hot-rolled sheets is large. 'Chu Gui 100101211 14 201134954 Homogenize' fermented iron particles after annealing When the diameter distribution is small, the amount of the strain increases, the granulation is increased, the strength is increased, and the formability is lowered. Further, the collective organization is also developed, and the r value becomes high and the shape freezeability is lowered. From the above, the rolling reduction ratio must be set to 80% or less. On the other hand, when the rolling reduction ratio is small, the amount of strain introduced is small, and recrystallization at the time of annealing is suppressed, and the structure is restored, and the formability is lowered. Therefore, the rolling reduction rate must be set to 40% or more. The average heating rate from the temperature range of 600 ° C to the soaking temperature · 1 to 30 〇 C / s is cold rolled and then annealed. In the present invention, under the control of the heat history during annealing, the strain amount after cooling is controlled while controlling the particle size and particle size distribution of the ferrite. Therefore, the manufacturing conditions at the time of annealing are important requirements. When the average heating rate from 600 C to the soaking temperature is small, recovery is carried out to suppress recrystallization. Therefore, the average heating rate must be set to 1 C/s or more. On the other hand, when the average heating rate is large, the occurrence of nucleation of recrystallization is suppressed during heating, and the nucleus is generated at the time of soaking, so that the particles are finely granulated. Therefore, the average heating rate must be set to 3 (TC). /s or less. Soaking temperature: 800 to 900 C, soaking time: 3 〇 to 200 seconds, the soaking treatment after heating, the recrystallization must be completed, the particle size is increased and the formability is improved. The temperature must be set to 800 ° C or higher. On the other hand, if the soaking temperature is too high, the ferrite iron is subjected to the metamorphosis of the Worthite iron, and the particle size is reduced in the inverted state after cooling. The heat temperature must be set to 900 ° C or higher. 100101211 15 201134954 Also, the right soaking time is short, and the target is on sB.], then, the day is not completed, or even if it is completed, the time for grain growth is short, 钤4 i1 is finely granulated and has reduced formability. Therefore, the soaking time during heating must be set to Λ π 丨 ^ ^ ^ ^ ^ 。 。 。 。. On the other hand, if the soaking time becomes longer, then the large particles are Joan eclipses small particles and grows larger, so The distribution of the particle size of the granular iron is quite small, and the particle size becomes large, which causes an appearance defect such as orange peel during press forming. The soaking time of the gemstone α and the prisoner must be set to 200 seconds or less. The average cooling rate from the soaking temperature to the temperature range of 5耽: 3~30〇C/s. The right sentence,,,, and the cold rolling speed after treatment are small, which promotes the growth of the ferrite particles, and the large book side. k is a small particle with a small size and the _ edge grows larger. Therefore, the particle size of the granules of the granules of the granules increases, and the particle size becomes large. When the pressure is formed, the appearance of the orange rind is poor. Up to 55 〇. (The average cooling rate in the temperature range must be set to 3t:/s or more. On the other hand, if the cooling rate is too high, the strength becomes high _£formability is lowered. Therefore, the average cooling rate must be set to 30. °C/s or less. After cooling from the soaking to 550 °C, the holding between 500 and 3003⁄4 may be appropriately cooled in accordance with the manufacturing equipment. Preferably, the temperature is from 550 °C to 550 °C. After cooling, 'then cool at the same cooling rate, ie, 3~3 (Tc/s cooling) With 500~3(9). C holding time: 30 seconds or more solid-solidified C, precipitated by carbonization_type, can improve aging. Therefore, it must be maintained at a temperature range of 300~5〇〇C which is easy to precipitate iron carbide. The upper limit of 100101211 16 201134954 is not specified. However, since the production efficiency is lowered for a long time, the upper limit of the holding time is preferably set to about 300 seconds. In addition, the temperature is kept at room temperature after being kept. However, the conditions are not necessarily specified. If it is properly carried out in accordance with the manufacturing equipment, the strain and elongation at room temperature: 〇5~2 〇% After annealing, the strain is added at the temperature to eliminate the yield point. Therefore, the strain added at room temperature must be set to 0.5% or more. On the other hand, if the elongation is increased, the yield point is increased and the formability is lowered. Therefore, it is necessary to set it to 2.0% or less. It is preferably u% or less. Further, strain imparted at room temperature may be milked and stretched, or combined with stretching and stretching. Also, in rolling, even if it is not lubricated. λ In the present invention, the usual melting method, electric furnace method, and the like can be suitably applied to the dissolution method. After the molten steel is turned into a steel embryo, it is directly or cooled and heated to perform hot rolling. After hot rolling is processed under the above-mentioned processing conditions, the coiling temperature is taken up by the above-mentioned coiling temperature. Then, after the general pickling, the above-described lyophilization is carried out. Regarding the retreat after cold rolling, heating, holding, and cooling were carried out under the above conditions. As needed, at 480. (: plating is performed by smelting zinc in the vicinity). After plating, the plating may be alloyed by reheating at 500 ° C or higher. In addition, when reheating is performed, it is necessary to grow the ferrite in the grain.耽 。 。 。 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 500~30 after reheating (TC hold time is set to 3〇 seconds
1001012H 17 201134954 以上為佳。另外，作為鍍敷浴溫的下限，為鑛左右。即， 於上述均減理後進躲崎鋅，並且進—步進行合金化處 理之It况#為熱履歷，若如下處理即可。上述均熱處理後， 上述均熱/置度至550。(：為止之溫度域以3〜3()t>c/s之平均冷 部速度予以冷卻，接著於冒c以下之溫度域巾冷卻進行熔 融鍍辞’其指遍〜;55Gt：之溫度域巾再加熱施彳丨合金化處 理，其後以500〜300。(：保持3〇秒鐘以上。作為保持時間， 以上述同樣之理由，設定為3〇〇秒鐘左右為佳。另外，保持 後若適當冷卻至室溫為止即可，更且，以〇5〜2〇%左右之 延伸率進行調質軋製。較佳為0.5〜1.5%。又，於退火途中 未施行鍍敷之情況，為提高耐腐蝕性亦可進行電鍍鍍鋅等。 更且’在冷軋鋼板和鍍敷鋼板上，亦可經由化成處理附加皮 膜。 由上述，取得老化後之成形性及形狀凍結性優異之冷軋鋼 板。根據上述所得之冷軋鋼板，於軋製方向、軋製45°方向、 軋製垂直方向之平均r值為12.以下、老化後之延伸度為40% 以上、老化後之屈服點延伸度為1.0%以下。另外’該等特 性係於20°C 6個月之老化處理後的平均r值、延伸度、屈服 點延伸度。 r值，與彎曲成形後產生的彎曲有關。彎曲成形中’彎曲 方向的r值變高，則沿著彎曲線之鞍型彎曲顯著發生。因 此，經由低r值化，提高加壓成形後之形狀凍結性為目的， 100101211 18 201134954 本發明中將平均r值設定為1.2以下。 延伸度與成形性極為相關，延伸度愈大，例如，可至高度 為止突出成形。因此，視需要延伸度愈大愈佳，且老化後之 延伸度設定為40%以上，進行深拉伸加工和突出加工，可嫁 保零件所要求的形狀。 上述加上本發明之鋼板，將老化後之屈服點延伸度設定為 1.0%以下’不僅剛製造鋼板後，於減低老化後之屈服點延 伸度下’抑制成形後的拉伸應變’可製造表面外觀優異的成 形品。 [實施例1] 將具有表1所示化學組成之鋼胚熔製後，再加熱並以表1 所示之最終出側溫度(FT)進行熱軋，並以平均冷卻速度：1〇 C/s冷部後，以表1所示之捲取溫度(CT)進行捲取處理。接 ,西参> ι、ι 士 -4 表1所示之軋縮率進行冷軋’並以表1所示之 條件進饤退火°接著’於室溫絲1所示之延伸率進行軋 縮，製造供試材。 另外，於表1中，由600°c至均熱溫度為止的平均加熱速 度為HR、均熱溫度為AT、均熱時間為HU、由均熱溫度至 55〇C為止的平均冷卻速度為CR、WC至3〇〇。(：的停溜時 間為Ht2。又，视』 仏成材No_4在途中於480。(：以熔融鋅進行鍍 敷處理，將表面作成熔融鍍鋅(GI)。供試材No.3在途中於 480 C以溶政鋅進行鎮敷後，於·。c再加熱，將表面作成 100101211 201134954 溶融鍍鋅(GA)。供試材版2未進行魏處理，將表 面作成電鑛(EG)。另外，供試材版4以外係由5贼至· C為止接著以表丨所示之CR同樣的冷卻速度予以冷卻。 對於根據上述所得之供試材，調查組織和機械特性。組織 係將軋製方向的板厚剖面以絲顯微鏡觀察，並且根據切斷 法求出組織的平_徑和粒徑分佈。結果，本實施例中，全 部供試材的組織為肥粒鐵相為99%以上。又由供試材以札 製方向作為拉伸方向’切出JIS 5號拉伸試驗片，並以2〇 。(：進行6個月的老化處理後’以拉伸速度i(w分鐘進行拉 伸試驗，測定屈服點延伸度(YP_E1)和全延伸度(ei)。又，『 值係由供試材的軋製方向、軋製45。方向、軋製垂直方向之 各方向切出：HS 5號拉伸試驗片，並以預應變15%測定由 軋製方向之r值(rL)、軋製45。方向之犷值㈨）、軋製垂直方 向C方向之r值⑹，將平均r_m)以〜=(rL+2rD+rc)/4 求出。所得之結果，與成分組成及製造條件合併示於表i。 100101211 20 20 4° 3 【111001012H 17 201134954 The above is better. In addition, the lower limit of the bath temperature is about or so. In other words, after the above-mentioned average reduction, the smectic zinc is introduced, and the state of the alloying process is further performed as the heat history, and the following treatment is sufficient. After the above soaking treatment, the above soaking/setting degree is 550. (The temperature range is cooled by the average cold section speed of 3~3()t>c/s, and then the temperature is cooled by the temperature zone below the c. The hot-plated word 'the finger' is overwritten; 55Gt: the temperature domain The towel is heated and subjected to alloying treatment, and thereafter, it is 500 to 300. (: Hold for 3 sec. or more. The holding time is preferably set to about 3 sec. for the same reason as above. Thereafter, if it is appropriately cooled to room temperature, the temper rolling may be carried out at an elongation of about 5 to 2%, preferably 0.5 to 1.5%. Further, plating is not performed during the annealing. In order to improve the corrosion resistance, it is also possible to perform electroplating, galvanizing, etc. Further, 'on the cold-rolled steel sheet and the plated steel sheet, the film may be added by chemical conversion treatment. The moldability and shape freezeability after aging are excellent as described above. Cold-rolled steel sheet. According to the above-mentioned cold-rolled steel sheet, the average r value in the rolling direction, the rolling 45° direction, and the rolling vertical direction is 12. The following, the elongation after aging is 40% or more, and the yield after aging The point extension is 1.0% or less. In addition, the characteristics are at 20 ° C 6 Average r value, elongation, and yield point elongation after aging treatment. The r value is related to the bending generated after bending. In the bending forming, the r value in the bending direction becomes high, and the saddle shape along the bending line Therefore, the purpose of the invention is to reduce the shape freezeability after press forming by a low r value. 100101211 18 201134954 In the present invention, the average r value is set to 1.2 or less. The elongation is highly correlated with the formability, and the elongation is more Large, for example, can be formed to a high degree of protrusion. Therefore, the greater the elongation as needed, the better, and the elongation after aging is set to 40% or more, and the deep drawing processing and the protruding processing are performed, and the required parts can be grafted. In the above-described steel sheet according to the present invention, the yield point elongation after aging is set to 1.0% or less. 'Under the production of the steel sheet, the tensile strain after the forming is suppressed under the yield point elongation after the aging is reduced. A molded article having an excellent surface appearance was produced. [Example 1] A steel slab having the chemical composition shown in Table 1 was melted, heated, and hot rolled at the final exit temperature (FT) shown in Table 1. After the average cooling rate: 1 〇 C / s cold part, the coiling temperature (CT) shown in Table 1 was taken up. Then, West ginseng > ι, ι 士-4 Table 1 The shrinkage rate was cold-rolled and subjected to annealing under the conditions shown in Table 1. Then, the test piece was produced by rolling at the elongation shown by the room temperature yarn 1. In addition, in Table 1, 600 ° C was obtained. The average heating rate up to the soaking temperature is HR, the soaking temperature is AT, the soaking time is HU, and the average cooling rate from the soaking temperature to 55 〇C is CR, WC to 3 〇〇. The slip time is Ht2. Further, 仏 仏 No No No No No No No No No No No No No No No No No. The test material No. 3 was applied to the 480 C on the way with solvate zinc, and then. c Reheat and make the surface 100101211 201134954 melt galvanized (GA). The test plate 2 was not subjected to Wei treatment, and the surface was made into an electric ore (EG). In addition, the test plate 4 was cooled by the same cooling rate as the CR shown in Table 5 from 5 thief to C. For the test materials obtained according to the above, the tissue and mechanical properties were investigated. The structure was observed with a wire thickness profile in the rolling direction, and the flatness and particle size distribution of the structure were determined according to the cutting method. As a result, in the present embodiment, the microstructure of all the test materials was 99% or more of the ferrite iron phase. Further, the JIS No. 5 tensile test piece was cut out from the test piece in the drawing direction as a stretching direction, and was set to 2 inches. (: After 6 months of aging treatment, 'stretching test was performed at a stretching speed i (w minutes, yield point elongation (YP_E1) and full elongation (ei). Further, the value is determined by the test material. The rolling direction, the rolling direction of 45, the direction of the rolling, and the perpendicular direction of the rolling were cut out: HS No. 5 tensile test piece, and r value (rL) in the rolling direction and rolling 45 were measured at a pre-strain of 15%. The value of the direction (9)), the r value (6) in the C direction of the rolling vertical direction, and the average r_m) are obtained by ~=(rL+2rD+rc)/4. The results obtained are shown in Table i in combination with the composition and manufacturing conditions. 100101211 20 20 4° 3 【11
犖 I 蚤 I I I I 5 1 1 s 5 I S I •u I s 1 Λ3, 1 v9 i s 3 —3 茶 1 -O 1 1 签 i ί -J _3 二 S 2 § n 2 二 Q 2 % Ξ g 9 承 承 承 承 1 g s s ο § 2 2 2 2 二 % 1 i § 1 § § § § s § § § § !§百 I 3 = cn )0 fS cn 〇s O = 〇\ 〇\ 镇1 g Q g s s Q Q <=>. Q Q Q Q Q Q g s § g § 8 § § § § § § § § § 6 I J£> o id jn jn JO in CJ o 一 g s § § b s § § § § § § § 8 8 ^ e § g i 1 S S § § § g o σ\ § g (V 空δ O u-i s 〇 o o o O o o O ί II g § § 5 § oq § § § § § g § 1 t 讲 $ R 5¾ !S $ $ s $ s $ $ is S _3 li b e 泰 辱 穿 g 赛 § 赛 § 1 § ^ G Εέ - 8 5? o § 1 o ? ? ^ e 1 1 § g 1 1 i i i i g i i fc 6 赛 o 5〇 ο oo g o § g § g § O oo § -¾ τ- CQ 1 0 1 1 謹 1 1 1 I 1 1 1 1 1 F 1 1 ο § to 1 1 1 1 1 1 t 1 1 1 Z. 議 i〇 I 画 謹 謹 議 謹 議 謹 I 議 i 議 I I § i i i i i i § 1 i i C/D ο § 0 1 U-J 1 0 1 0 1 O § 〇 1 0 1 〇 § O § 0 1 O § 0 1 0. 1 § I 1 § 1 1 1 1 1 1 1 1 I ντι 3 I § § 3 5 jn 5 JO Ξ JO s § § i § 访 § I 1 1 § § § § § § § § § u 1 1 I 1 I § § i § 1 1 1 1 — (N m VO 卜 00 〇\ o = Ci CO 13 s ll-olool 201134954 若根據表卜具有本發明之粗成，且以本發明之製造方法 所製造_板(發日_)，練鐵平均粒徑為iG〜鄉m之範圍 内，且，標準偏差(〜)為〇_3()以上。其結果可取得乳製方 向、軋製45。方向、軋製垂直方向之平均r值為i 2以下、 老化後之屈服點延伸度為1〇%以下、且老化後之延伸度 (Elm)為40%以上之老化後之成形性及形狀凍結性優異的冷 軋鋼板。 相對地，製造方法為本發明範圍外的鋼板（比較鋼），肥粒 鐵平均粒徑或標準偏差（σΑ)為範圍外，平均r值、老化後之 屈服點延伸度及老化後之延伸度(Ε1)任一者均為差。 於圖2表示供試材No.l〜8，（FT-Ar3)對σΑ的影響，於圖 3表示供試材No.l〜4.9，CT對σΑ造成的影響。 由圖2可知’最終出側溫度(FT)為(Ar3_1〇〇〇c)〜Ar3，標準 偏差（σΑ)可設定成〇.3〇以上。 由圖3可知，可將捲取溫度(CT)設定為未滿55〇t>c ,標準 偏差（σΑ)可設定成〇.3〇以上。 【圖式簡單說明】 圖1表示σΑ對老化後之屈服延伸度(γρ-叫與延伸度(Ε1) 所造成之影響圖。 圖2表示（精軋之最終出側溫度(FT)_Αγ3#+〜所造成之影 響圖。 圖3表示捲取溫度(CT)對σΑ所造成之影響圖。 100101211 22荦I 蚤IIII 5 1 1 s 5 ISI •u I s 1 Λ3, 1 v9 is 3 —3 Tea 1 -O 1 1 Sign i ί -J _3 Two S 2 § n 2 Two Q 2 % Ξ g 9 Undertaking Inheritance 1 gss ο § 2 2 2 2 2% 1 i § 1 § § § § s § § § § § 100 I 3 = cn )0 fS cn 〇s O = 〇\ 〇\ Town 1 g Q gss QQ <=>. QQQQQQ gs § g § 8 § § § § § § § § § 6 IJ£> o id jn jn JO in CJ o a gs § § bs § § § § § § § 8 8 ^ e § gi 1 SS § § § go σ\ § g (V empty δ O ui s 〇ooo O oo O ί II g § § 5 § oq § § § § § g § 1 t speak $ R 53⁄4 !S $ $ s $ s $ $ is S _3 li be Thai swearing g 赛 赛 § 1 § ^ G Εέ - 8 5? o § 1 o ? ? ^ e 1 1 § g 1 1 iiiigii fc 6 赛o 5〇ο oo go § g § g § O oo § -3⁄4 τ- CQ 1 0 1 1 1 1 1 I 1 1 1 1 1 F 1 1 ο § to 1 1 1 1 1 1 t 1 1 1 Z. Discussion i〇I Painting I would like to discuss this issue. I discuss II § iiiiii § 1 ii C/D ο § 0 1 UJ 1 0 1 0 1 O § 〇1 0 1 〇§ O § 0 1 O § 0 1 0. 1 § I 1 § 1 1 1 1 1 1 1 1 I ντι 3 I § § 3 5 jn 5 JO Ξ JO s § § i § Visit § I 1 1 § § § § § § § § § u 1 1 I 1 I § § i § 1 1 1 1 — (N m VO 卜 00 〇 \ o = Ci CO 13 s ll-olool 201134954 According to the table, the invention has the coarseness and the manufacturing method of the invention Manufacture_board (day _), the average particle size of the iron is in the range of iG to township m, and the standard deviation (~) is 〇_3() or more. As a result, the milk direction and rolling 45 can be obtained. Formability and shape freeze after aging in the direction and the vertical direction of rolling in the range of i 2 or less, the yield point elongation after aging is 1% or less, and the elongation (Elm) after aging is 40% or more. Excellent cold rolled steel sheet. In contrast, the manufacturing method is a steel sheet (comparative steel) outside the scope of the invention, and the average grain size or standard deviation (σΑ) of the ferrite grain is outside the range, the average r value, the yield point elongation after aging, and the elongation after aging. (Ε1) Any one is poor. Fig. 2 shows the influence of the test materials No. 1 to 8, (FT-Ar3) on σΑ, and Fig. 3 shows the influence of CT on the σΑ by the test materials No. 1 to 4.9. As can be seen from Fig. 2, the final exit temperature (FT) is (Ar3_1〇〇〇c) to Ar3, and the standard deviation (σΑ) can be set to 〇.3〇 or more. As can be seen from Fig. 3, the coiling temperature (CT) can be set to less than 55 〇 t > c, and the standard deviation (σ Α) can be set to 〇.3 〇 or more. [Simple description of the diagram] Figure 1 shows the effect of σΑ on the yield elongation after aging (γρ-call and elongation (Ε1). Figure 2 shows (final exit final temperature (FT)_Αγ3#+ Figure of the effect of the coiling temperature (CT) on σΑ. 100101211 22