TW554047B - Extra deep drawing with resistance to secondary work embattlement cold-rolled steel sheet - Google Patents

Abstract

A cold-rolled steel sheet consisting essentially of 0.001 to 0.006 wt% C, 0.001 to 0.1 wt% Si, 0.001 to 0.5 wt% Mn, 0.001 to 0.02 wt% P, 0.001 to 0.02 wt% S, 0.01 to 0.1 wt% Al, 0.001 to 0.006 wt% N and 0.01 to 0.1 wt% Ti, satisfying the requirement of [Ti*] > (48/12)x[C] and [C] < (12/32)x[S] (where [Ti*]=[Ti]-3.42x[N]-1.5x[S] and [Ti], [C], [N] and [S] are the compositions in wt% of Ti, C, N and S), the balance being substantially iron and inevitable impurities, can be produced by casting, hot rolling with reheating temperatures lower than 1200 DEG C and finish-rolling at temperatures higher than Ar3 point, conducting coiling at 760 DEG C or lower, and conducting cold rolling at a rolling reduction of 70% or higher and annealing at 700 DEG C or higher in this order to possess superior deep drawing properties with r-value greater than 2.0 and secondary work embattlement temperature less than -60 DEG C.

Description

554047 - —---ES_凹 113127____ 年 η 日 修正__ 五、發明說明（1) 本發明係有關於一種超深衝性且具抗二次加工脆性之 冷軋鋼片組成物，特別是指—種r值大於2. 〇、轉脆溫度 小於-60 且成形性佳的冷軋鋼片組成物。 才女’近年來由於况車零件之形狀更趨向複雜，因此汽 f用鋼片的成形性之要求即愈來愈高；以油箱為例，由於 汽車各部空間位置在設計時係先考慮到方便性、安全性及 舒適性’因此待汽車之主要機件設計完成後，所剩下之空 間才留給油箱設置，因而油箱之造形便趨向不規則且更為 複雜；同時，為了因應此_趨勢，成形油箱之鋼片非要具 有極佳之成形性才仔以機械衝壓出如此形狀複雜之油箱， 是故，提高鋼片之成形性乃為鋼鐵公司致力研究發展之目 標0 近一十幾年來’一種極低碳加鈦或加鈮之冷軋鋼片被 發明出來，此種鋼片之原理乃是在極低碳中添加足夠的鈦 或銳，利用鈦或鈮與碳有強烈結合性而將鋼中之碳、氮固 定住，再經適當之製程，即可得到很高之r值且成形性良 好之鋼片；然而，該鋼片經深衝成形後，因其晶界極為清 淨’往往致使該鋼片容易發生縱向破裂，即所謂的二&amp;加 工脆化，進而造成使用上的困擾；而為了解決二問:7 ‘ 有三種方法被提議出來： 1 ·添加硼（B): 在鋼片中添加硼可使碳 界而改善上述之問題；但硼 溫度且降低鋼片之成形性， 求的汽車組件應用。 偏析至晶界，藉以強化晶 的添力π會提高鋼片再結晶 不利於有較嚴格成形性要554047------ ES_ concave 113127____ year _ day correction __ V. Description of the invention (1) The present invention relates to a cold-rolled steel sheet composition with ultra-deep drawability and resistance to secondary processing embrittlement, especially referring to -A kind of cold-rolled steel sheet composition with r value greater than 2.0, transition temperature less than -60, and good formability. Talented women 'In recent years, the shape of car parts has become more complex, so the requirements for the formability of steel sheets for autos have become higher and higher. Taking the fuel tank as an example, because the space of various parts of the car is designed with convenience in mind , Safety and comfort '. Therefore, after the design of the main parts of the car is completed, the remaining space is left for the fuel tank to be set, so the shape of the fuel tank tends to be irregular and more complex; at the same time, in response to this trend, The steel sheet of the formed oil tank must have excellent formability before mechanically punching out such a complicated shape of the oil tank. Therefore, improving the formability of the steel sheet is the goal of steel companies dedicated to research and development. An extremely low carbon titanium or niobium cold rolled steel sheet was invented. The principle of this type of steel sheet is to add enough titanium or sharp to extremely low carbon, and use the strong binding of titanium or niobium to carbon to make steel The carbon and nitrogen in the steel are fixed, and then through a proper process, a steel sheet with high r value and good formability can be obtained; however, after deep drawing, the steel sheet is extremely clean because of its grain boundaries. The The sheet is prone to longitudinal cracking, which is the so-called second &amp; processing embrittlement, which causes trouble in use; and in order to solve the second question: 7 'Three methods have been proposed: 1 · Add boron (B): In the steel sheet Adding boron can improve the above problems in the carbon interface; however, boron temperature and lower formability of the steel sheet are required for automotive component applications. Segregation to the grain boundary, by which the added force of the strengthening grain π will increase the recrystallization of the steel sheet, which is not conducive to stricter formability.

第5頁 554047 ,89113127^ 五、發明說明（2) 2 ·添加不足量合金 使碳偏析至晶界，藉 結晶前即已存在，致 再結晶集合組織的成 在鋼片中添加不足量合金可 之強化晶界；但因為固溶碳在未 使其於退火時將大幅弱化{111} 長進而降低鋼片之成形性。 3 ·高溫退火： H以南溫退火即可使鋼片中之Nb或Ti碳化物 回溶至基地，因此可使碳偏析至晶界進而強化晶界； 然而，由於鋼片中之固溶碳於完成再結晶後才存在於 基地，退火後之材料可保有強的U11}再結晶集合组 織而有良好成形性；❻有研究報告指丨，若該鋼片在 9 0 0_t^退火所得到轉脆溫度反而比在82〇。〇退火者高， 二頁示同’皿退火並不能完全改善鋼片二次加工脆化之問 題’其原因可能是碳未偏析至晶I ’或是冷卻時重新 本案發明者之一為克服上 1 0 3 8 9 2之專利申請案向鈞局 發發明第60 763號專利權在案 添加鋼中，大幅降低鋁含量， 固溶較多量鈮及碳原子，冷軋 冷軋晶界或差排上，進而有利 設計，可得到r值大於18之高 利仍具有極低鋁含量之鍊鋼製 不能滿足目前之需求。 述缺點，曾以申請案號為8 〇 提出申請，並蒙獲 鈞局核 ’其主要製程是在極低碳鈮 並利用低溫盤捲，使基地中 退火時，才使碳化鈮析出在 於成形性之晶粒成長；如此 成形性冷軋鋼片，然，該專 成困難，以及r值大於1. 8已 本案明人現任職於中國鋼鐵股份有限公司之研發Page 5 554047, 89113127 ^ V. Description of the invention (2) 2 · Adding an insufficient amount of alloy to segregate carbon to the grain boundary, which already exists before crystallization, resulting in a recrystallized aggregate structure. Adding an insufficient amount of alloy to the steel sheet can It strengthens the grain boundaries; however, the solid solution carbon will significantly weaken the {111} length when it is not annealed, thereby reducing the formability of the steel sheet. 3 · High temperature annealing: Annealing at the south temperature of H can dissolve the Nb or Ti carbides in the steel sheet to the base, so the carbon can segregate to the grain boundary and then strengthen the grain boundary; however, due to the solid solution carbon in the steel sheet It only exists at the base after recrystallization is completed, and the annealed material can maintain a strong U11} recrystallized aggregate structure and have good formability; a research report indicates that, if the steel sheet is obtained by annealing at 9 0 0_t ^ Instead, the brittle temperature is higher than 82 °. 〇The annealing rate is high. The second page shows that the same as' the plate annealing does not completely improve the embrittlement of the steel sheet during secondary processing. 'The reason may be that the carbon has not segregated to the crystal I' or one of the inventors of this case remedied the problem during cooling. 1 0 3 8 92 patent application issued to Jun Bureau Invention No. 60 763 Patent added to the file, greatly reducing the aluminum content, solid solution large amount of niobium and carbon atoms, cold rolled cold rolled grain boundaries or differential emissions In addition, it is advantageous to design, and it can be obtained that a chain steel made of a high profit with an r value greater than 18 and still having a very low aluminum content cannot meet the current demand. The above-mentioned shortcomings have been filed with an application number of 80, and won the Bureau's approval. Its main process is to form the niobium carbide when the base is annealed in the extremely low carbon niobium and the low temperature coil is used to anneal. Grain growth; such a formable cold-rolled steel sheet, however, the specialization is difficult, and the r value is greater than 1.8.

554047 索號89113拉—7 一 年 發明說明（3) :位，對於金屬材質之研究已有多年嫻熟之經歷 且 有充沛之學識素養’此刻鑒於習知方法仍有前述之缺&amp; :利因素有待改善，遂萌生創意，經一番潛心研究及多次 式驗之後，終於有本發明產生。 故，本發明之主要目的，乃在提供一種超深衝性且具 几一次加工脆性之冷軋鋼片組成物，且同時並具有^值 於2· 〇、轉脆溫度小於-60 i且成形性佳之功效^。 η 五 修正 依據上述之目的，本發明之主要特徵在於，該超深衝 且具抗二次加工脆性之冷軋鋼片組成物至少包含有 0·〇〇1〜0·0 0 6重量百分比之碳（〇，〇 〇〇1〜〇1重量百分比 ^f(Si) ,0.001 〜0.5 重量百分比之錳（Μη) 置百分比之磷（P)，〇· 〇(Π〜〇· 〇2重量百分比之硫（s)， • 0—1〜〇· 1重量百分比之鋁（Α1)，〇· 001〜〇· 〇〇6重量百分比 之氮（Ν)，單獨添加的〇. (Π〜〇· 1重量百分比之鈦（Ti);再554047 Cable No. 89113 La-7 Description of the invention for one year (3): bit, has been experienced in the study of metal materials for many years and has ample knowledge and literacy 'At this moment in view of the conventional methods there are still the aforementioned shortcomings &amp; There is still room for improvement, and a creative idea emerges. After a lot of research and many tests, the invention finally came into being. Therefore, the main object of the present invention is to provide a cold-rolled steel sheet composition with ultra-deep drawability and several processing brittleness, and at the same time, it has a value of 2 〇, a transition temperature of less than -60 i, and forming The effect of good sex ^. η Five Modifications According to the above purpose, the main feature of the present invention is that the cold-rolled steel sheet composition with ultra-deep drawing and resistance to secondary processing embrittlement contains at least 0.000 to 0 · 0 0 6 weight percent carbon (〇, 〇〇〇〇〇〇〇1 ～ 〇1 weight percent ^ f (Si), 0.001 ~ 0.5 weight percent manganese (Mn), percentage of phosphorus (P), 〇 (〇〜〇. 〇2 weight percent of sulfur (S), • 0-1 to 〇. 1 weight percent of aluminum (Α1), 〇. 001 to 〇. 〇〇006 weight percent of nitrogen (N), separately added 〇. (Π ~ 〇. 1 weight percent Of titanium (Ti);

者，上述合金成份需滿足Ti*&gt; (48/12) XC及C&lt; (12/32) X (所有元素均以重I百分比表示，而48、12、14、32分別 為Ti、C、N、S之原子量，其中，Ti*= Ti 一 3·42χΝ — ΐ 5χ S )，另外，再將上述該等組成物與實質之鐵與不顯著之 雜質，混合後，經造塊或連鑄所得之鋼胚在低於丨2 〇 〇它進 行鋼胚再加熱，並在高於Ar3點以上之溫度完成熱軋，且 同時在低於7 6 0 °C做盤捲，而在高於7 0 %冷軋率冷軋後在結 晶溫度70 0 °c以上做連續退火處理而獲得之超深衝性冷軋 鋼片’使其具有r值大於2.0、轉脆溫度小於— 60°c且成形 性佳之功效者。 緣 是’本發明之超深衝性且具抗二次加工脆性之冷軋The above alloy composition must satisfy Ti * &gt; (48/12) XC and C &lt; (12/32) X (all elements are expressed as percentages of heavy I, and 48, 12, 14, 32 are respectively Ti, C, The atomic weight of N and S, among them, Ti * = Ti-3.242 × N — ΐ 5χ S). In addition, the above-mentioned compositions are mixed with substantial iron and insignificant impurities, and then agglomerated or continuously cast. The obtained steel billet is reheated at a temperature lower than 2000, and hot rolled at a temperature higher than the Ar3 point, and at the same time coiled at a temperature lower than 7 60 ° C, and at a temperature higher than 7 0% cold-rolling rate Ultra-deep drawing cold-rolled steel sheet obtained by continuous annealing at a crystallization temperature above 70 0 ° C after cold rolling, so that it has an r value greater than 2.0, a transition brittle temperature less than -60 ° c, and formability Good effect. The margin is ‘cold-rolled with ultra-deep drawability and resistance to secondary working embrittlement of the present invention

m _ 554047 修正 曰 89118197 五、發明說明（4) 鋼片組成物至少包含有〇· 〇〇卜〇· 00 6重量百分比之碳（(：）， 0.001〜0.1重量百分比之矽（Si) ,〇〇〇1〜〇·5重量百分比 之猛（Μη)，〇·001〜〇 〇2重量百分比之磷（Ρ)，〇 〇〇1〜〇 02重量百分比之硫（S)，0. (Π〜0· 1重量百分比之鋁（Α1 )，· 0.001〜0.006重量百分比之氮（Ν)，單獨添加的〇·01〜〇1重 量百分比之鈦（T i )，以及實質之鐵與不顯著之雜質等成份 ’另外’再將該等組成物混合後，經造塊或連鑄所得之^ 胚在低於1200 °c進行鋼胚再加熱，並在高於Ar3點以上之 溫度完成熱軋，且同時在低於76 0 t做盤捲，而在高於 冷軋率冷軋後在結晶溫度70 0乞以上做連續退火處理而^ 得超深衝性冷軋鋼片，再者，該超深衝性冷軋鋼片之八^ 成份，滿足Ti*&gt;(48/12) XC 及C&lt;(12/32) XS (所有元 以重a:百分比表示，而48、12、14、32分別為Ti、c、n句 S之原子量，其中，Ti* = Ti 一 3·42χΝ-1·5χδ)，同時，龙 並具有r值大於2· 〇、轉脆溫度小於—6〇 t且成形性 &gt;、 效者。 乂工力 為達上述之目的，茲舉本發明一較佳實施例，並 實驗=表說明如後，俾使貴審查委員可對本發明之二 、目的、特徵及功效有更進一步之了解。 踅點 首先，第-圖所示係本發明之合金成份 其中該縱軸是Ti*(N、S結合後所剩下之？1， *圍圖， 42 XN-1. 5 XS)，橫軸是C ; Ti* = 4 y r 〜3· 之下限；C = (3/8) XS為C添加量之^之斜/為Τΐ*添加量 所設定範圍區；第Π區為C添加過息々，第I區為本發明 从·筮TTT F炎Τ ·大π 口 r* 里區’有T i C微細析出 物，弟瓜1£為Ti 添加不足區，右m_554047 Amendment 89118197 V. Description of the invention (4) The composition of the steel sheet contains at least 0.006 weight percent carbon ((:), 0.001 to 0.1 weight percent silicon (Si), 〇 〇〇1 ～ 〇.5 weight percent of fierce (Mη), 0.001 ~ 〇02 weight percent of phosphorus (P), 〇〇001 ～ 〇02 weight percent of sulfur (S), 0. (Π ~ 0.1 weight percent aluminum (Α1), 0.001 to 0.006 weight percent nitrogen (N), separately added 0.01 to 0.001 weight percent titanium (T i), and substantial iron with insignificant impurities After the other components are mixed with other ingredients, the ^ embryo obtained by agglomeration or continuous casting is reheated at a temperature below 1200 ° c, and hot rolled at a temperature higher than the Ar3 point, and At the same time, coiling is performed below 76 0 t, and after cold rolling above the cold rolling rate, continuous annealing treatment is performed at a crystallization temperature of more than 70 ° C to obtain an ultra-deep drawing cold-rolled steel sheet. Furthermore, the ultra-deep drawing Eighth composition of cold-rolled steel sheet, which meets Ti * &gt; (48/12) XC and C &lt; (12/32) XS (all yuans are expressed by weight a: percentage, and 48, 12 14, 32 are the atomic weights of S, Ti, c, and n, respectively, where Ti * = Ti-3.42xN-1 · 5xδ), meanwhile, the dragon has an r value greater than 2. ·, and its brittle temperature is less than -6. In order to achieve the above-mentioned purpose, a preferred embodiment of the present invention will be given, and experiments will be described in the following table, so that your review committee can make a second, purpose, The characteristics and effects are further understood. 踅 Points First, the first figure shows the alloy composition of the present invention, in which the vertical axis is Ti * (N, S left after combining? 1, * circle, 42 XN -1. 5 XS), the horizontal axis is C; Ti * = 4 yr ~ 3 · lower limit; C = (3/8) XS is the slope of ^ of the C addition amount / is the range set by Τΐ * addition amount; Area Π is the addition of C. The area I of the present invention is from TTT F Yan T. There is a fine precipitate of T i C in the large π mouth r *. right

---------餘的固溶C ;同時兩軸--------- The remaining solid solution C; two axes at the same time

IM 554047 _____案號89113127_年月日 修正___ 五、發明說明（5) 均以重量百分比表示。 本發明超深衝性且具抗二次加工脆性之冷軋鋼片組成 物大體上至少包含有碳（C)、矽（Si)、錳（Μη)、磷（P)、硫 (S)、鋁（Α1)、氮（Ν)、單獨添加的鈦（Ti)或鈮（Nb)，其中 上述各成份之含量為： 破（C) · 0.001〜0.006之重量百分比 石夕（Si) :0.001〜0.1之重量百分比 猛（Mn) :0.001〜0.5之重量百分比 磷（Ρ) :0·0(Π〜0.02之重量百分比 硫（S) :0.001〜0.02之重量百分比 銘（Al) :0·01〜0.1之重量百分比 氣（Ν) · 0.001〜〇·〇〇6之重量百分比 鈦（Ti):單獨添加〇·〇ι〜〇·ι之重量百分比或 妮（Nb):複合添加〇·〇〇5〜〇〇4之重量百分比 同時，上述合金成份需滿sTi*&gt;(48/12) xc &amp;c&lt;(12 /32) XS等兩方程式（所有元素均以重量百分比表示，而48 、12、14、32分別為Ti、c、N、s之原子量，其中，η “ 丁卜3· 42 XN-1. 5 XS)。 本發明之化學成份限制理由： 極低碳鋼添加Ti的目的是用來鋼中固溶碳（c)，避免 碳於鋼片再結晶時阻擋{111}再結晶集合組織的成長 T而，低鋼t成形性；然而，N及S與Ti之結合力強 C結合刖，T i在鬲溫即與N、s結合而 的Y才有f/與C結合，因此剩下的Ti乃係為；下 —般以T i *表示： q β双刃i 1 554047 ---tl· 891131i7_年月 曰 倏正_ 五、發明說^ --—IM 554047 _____ Case No. 89113127_ Year Month Day Amendment ___ V. Description of the invention (5) All are expressed by weight percentage. The cold-rolled steel sheet composition with ultra deep drawability and resistance to secondary processing brittleness of the present invention generally includes at least carbon (C), silicon (Si), manganese (Mn), phosphorus (P), sulfur (S), and aluminum. (A1), nitrogen (N), separately added titanium (Ti) or niobium (Nb), wherein the content of each of the above components is: broken (C) · 0.001 to 0.006 weight percent Shi Xi (Si): 0.001 to 0.1 Weight percentage (Mn): 0.001 ~ 0.5 weight percent Phosphorus (P): 0 · 0 (Π ~ 0.02 weight percent Sulfur (S): 0.001 ~ 0.02 weight percent Ming (Al): 0 · 01 ~ 0.1 Weight percentage of gas (N) · 0.001 to 0.005 weight percentage of titanium (Ti): individually added weight percentage of 〇〇〇 ～ 〇 · ι or Ni (Nb): compound addition 〇〇〇〇5〜 At the same time, the above alloy composition must be sTi * &gt; (48/12) xc &amp; c &lt; (12/32) XS and other two equations (all elements are expressed by weight percentage, and 48, 12, and 14, 32 are the atomic weights of Ti, c, N, and s, respectively, in which η "Dibu 3.42 XN-1. 5 XS). Reasons for the limitation of the chemical composition of the present invention: The purpose of adding Ti to very low carbon steel is to Lay steel dissolves carbon (c) to prevent carbon from blocking the growth of the {111} recrystallized aggregate structure when the steel is recrystallized. However, the formability of steel is low; however, the bonding force of N and S and Ti is strong. Ai, T i is combined with N and s at Y and f / is combined with C, so the remaining Ti is: T i *: q β double-edged i 1 554047- --tl · 891131i7_Yueyue Yuezheng_ V. The Invention ^ ---

Ti* = Ti-(48/14) XN-（48/32 ) XS 成τ · Tl *將會進一步單獨與C結合成TiC，或與C及S複合形 hhS2 ;若單獨與C結合成TiC則可用下式表示：Ti * = Ti- (48/14) XN- (48/32) XS into τ · Tl * will be further combined with C alone to form TiC, or combined with C and S hhS2; if combined with C alone to form TiC then Can be expressed by:

[Ti ] + [C] -&gt;TiC 每—f中[Ti]及[C]表鋼料中固溶碳c及Ti元素，該式表示 添莫耳之[Ti]將可固定住一莫耳原子之[C];同時，所 之有效Ti(Ti*)之莫耳數必須大於鋼材中c之莫耳數， 之I將鋼材中所有C固定住，即Ti* (莫耳數）&gt;c(莫耳數） 〖·、件須滿足；而若將此條件改為重量百分比，即成為下[Ti] + [C]-&gt; TiC [Ti] and [C] solid solution carbon c and Ti elements in each -f of the steel, this formula indicates that [Ti] added by Moore will fix one Mo Ear atomic [C]; At the same time, the effective number of moles of Ti (Ti *) must be greater than the number of moles of c in the steel, and I fixes all C in the steel, that is, Ti * (moles) &gt; c (mol number) 〖·, the pieces must be satisfied; and if this condition is changed to weight percentage, it becomes the following

Ti* (重量百分比）&gt;(48/12)xC(重量百分比） 又’.由於[Ti]與[c]有可能不直接形成Tic，而會尋找 :的TiS析出物附著其上，與之形成丁丨义心析出物，其 久應式可用下式表示： CTi ] + [C]+TiS(1/2 ) XTi4C2S2 由於Ti^S2析出物比Tic析出物粗大，再結晶時有利 力 再、’Ό曰曰組織的成長而提高鋼片成形性，因此如何增 口^似2析出物而減少nc析出物是為改善鋼片成形性之 * ，另由TuCA析出物分子式可知，c之莫耳數與s之莫 ，才目同，換S之，若鋼中添加之C莫耳數大於s之莫耳數 ’則多餘之C 只能盘τ i社人士 τ · η mTi * (percent by weight) &gt; (48/12) xC (percent by weight) and '. Since [Ti] and [c] may not directly form Tic, they will look for: TiS precipitates attached to it, and The Ding Yixin precipitate is formed, and its long-term formula can be expressed by the following formula: CTi] + [C] + TiS (1/2) XTi4C2S2 Because the Ti ^ S2 precipitate is coarser than the Tic precipitate, the force of recrystallization is better. It is said that the growth of the structure improves the formability of the steel sheet, so how to increase the size of the 2 precipitates and reduce the nc precipitates is to improve the formability of the steel sheet. In addition, according to the molecular formula of the TuCA precipitate, it is known that the molar number of c and The same is true for s. For S, if the number of C moles added to the steel is greater than the number of moles of s, then the excess C can only be determined by τ i 社 人 τ · η m

钍人占τ· r ς紅山i 口成TlC ;因此為確保C與Ti、S ΐt 則c(莫耳數）&lt;s(莫耳數）之條件必 々滿足二將此條件改為重量百分比，即成為下式： t上述_之結果可整理成^一 s ;而圖中所示出之三個The person accounts for τ · r ς Hongshan i mouth into TlC; therefore, in order to ensure that C and Ti, S ΐt then the condition of c (mol number) &s; s (mol number) must be met. This condition is changed to weight percentage , Which becomes the following formula: t The result of the above _ can be organized into ^ one s; and the three shown in the figure

第10頁 C(重1百分比）&lt;(12/32)xs(重量百分比） 554047Page 10 C (weight 1 percentage) &lt; (12/32) xs (weight percentage) 554047

ί亚f I f (Ti* = 4 XC直線上方、c=(3/8) xSi線左側）之 恭 斤 务為Ti S及Ti^S2，加上固溶[Ti ]，此區即為本 ^明s所設定之範圍區；第ϋ區（THHXC直線上方、C--，) XS^線右側）除了 C與Ti、S結合成Ti4C2S2析出物外 把山C的^加使得多餘的C必須與T1直接反應形成τ 1 C微細 物’加上固溶[Ti];第m區（Ti*=4 XC直線下方）則因 1的，加=足’而有多餘的固溶C無法固定住；由於第Π :及第H[區有τ i C微細析出物及多餘的固溶c，而當鋼片冷 L退火時會阻擋{丨丨丨丨再結晶集合組織的成長而降低鋼片 的成形性’因此本發明係以Ti*&gt;(48/12) xc及c&lt;(12/32) xs等兩方程式限制Ti&amp;c含量，使之落入第工區。 山除此之外，各合金元素限制之理由說明如下·· 碳··為了 ^有優異之衝壓成形性，碳含量愈低愈好，又， 如果奴含量超過〇· 〇〇6重量百分比，則需要多量之鈦 添加量，成本無謂增加，形成浪費。 矽·石夕不必刻意添加，其含量若超過〇^重量百分比，則 表面品質變差，影響後續作業如鍍面處理等，且鋼材 之成形性也變差。 錳：錳也非刻意添加，其可改善熱加工性，但是添加過量 ，會降低鋼片成形性，因此設定在〇·5重量百分比以 下0 磷 填為鋼中不純物，容 應控制在0 · 0 2重量百 容易造成鋼片之二次ί Asian f I f (Ti * = 4 above XC straight line, c = (3/8) xSi to the left of the line), the service is Ti S and Ti ^ S2, plus solid solution [Ti], this area is this ^ The range area set by Ming s; the third area (above THHXC straight line, C--,) XS ^ line right side) In addition to C and Ti, S combined to form Ti4C2S2 precipitates, add ^ of mountain C so that excess C must be It reacts directly with T1 to form τ 1 C fines' plus solid solution [Ti]; the m-th area (below Ti * = 4 XC line) is because of 1, plus = foot, and there is excess solid solution C that cannot be fixed. ; As the Π: and H [regions have τ i C fine precipitates and excess solid solution c, when the steel sheet is cold L annealed, it will block the growth of the recrystallized aggregate structure and reduce the steel sheet ’s Formability 'Therefore, the present invention restricts the Ti &amp; c content by two equations, such as Ti * &gt; (48/12) xc and c &lt; (12/32) xs, so that it falls into the first work area. In addition to this, the reasons for the limitation of each alloy element are explained as follows: · Carbon · In order to have excellent stamping formability, the lower the carbon content, the better, and if the slave content exceeds 0.006% by weight, then A large amount of titanium is required, and the cost is increased unnecessarily, resulting in waste. It is not necessary to add silicon · shixi. If its content exceeds 0% by weight, the surface quality will deteriorate, which will affect subsequent operations such as plating treatment, and the formability of steel will also deteriorate. Manganese: Manganese is not intentionally added, which can improve hot workability, but excessive addition will reduce the formability of the steel sheet. Therefore, it is set to less than 0.5% by weight. 0 Phosphorus is impure in the steel, and the capacity should be controlled at 0 · 0 2 weight hundred is easy to cause secondary steel sheet

成鄉震會班左士泌尖Τ 易偏析至晶界而弱化晶界，因此 分比以下，若超過此上限，則很 加工脆化及焊接脆化之現象。 554047 曰 案號89113127_年月 五、發明說明（8)The Chengxiang Zhenhui class Zuo Shi Bijian T tends to segregate to the grain boundary and weaken the grain boundary. Therefore, if the ratio is below the upper limit, it will be processed and embrittlement. 554047 said case number 89113127_Year 5. Description of the invention (8)

Ti含量，因此其含量愈低愈好，以小於0.02重量百分 比為宜。 鋁：主要用來作為煉鋼時脫氧之用，鋁含量低於〇.〇1重量 百分比時，可能造成脫氧不足，反之，高於0.1重量 百分比時，會形成過多介在物而影響成形性。 氮：氮經常會與鈦形成TiN，而降低有效Ti含量，因此其 含量愈低愈好，以小於0 · 0 0 6重量百分比為宜。 鈦：鈦主要用來固定鋼中之碳、氮及硫，如果添加太少， 則無法固定碳、氮及硫，鋼片之成形性變差；如果添 加過多’因排擠碳強化晶界之作用，不但降低抗二次 加工脆化之能力，也形成浪費；以小於〇 · 1重量百分 比為宜。 鈮：是需要用來補充固定鋼中之碳，並有細化晶粒而提高 成形性及抗一次加工脆化之能力；如果添加太少則無 上述之作用’添加太多’因提高鋼片再結晶溫度，抑 制{111 }再結晶集合組織的成長，反而降低鋼片成形 性；以小於0· 04重量百分比為宜。 於上述本發 以下列之製程為 硫（S)、銘（A1) ’ 重量百分比混合 所得之鋼胚在低 點以上之溫度完 在於70%〜90% 冷 續退火溫度最少 明之組成物製成超深衝性冷軋鋼片時，係 之’將碳（C)、矽（si)、錳（Mn)、磷（p)、The content of Ti is therefore as low as possible, preferably less than 0.02% by weight. Aluminum: It is mainly used for deoxidation during steelmaking. When the aluminum content is less than 0.01% by weight, insufficient deoxidation may be caused. On the other hand, when it exceeds 0.1% by weight, excessive inclusions may be formed to affect formability. Nitrogen: Nitrogen often forms TiN with titanium and reduces the effective Ti content, so the lower the content, the better, preferably less than 0. 0 0 6 weight percent. Titanium: Titanium is mainly used to fix carbon, nitrogen, and sulfur in steel. If too little is added, carbon, nitrogen, and sulfur cannot be fixed, and the formability of the steel sheet is deteriorated. If it is added too much, it will strengthen the grain boundary by squeezing carbon. , Not only reduce the ability to resist secondary processing embrittlement, but also form waste; preferably less than 0.1 weight percent. Niobium: It needs to be used to supplement the carbon in the fixed steel, and has the ability to refine the grains to improve formability and resistance to embrittlement during primary processing; if it is added too little, it will not have the above effect. The recrystallization temperature suppresses the growth of the {111} recrystallized aggregate structure, but decreases the formability of the steel sheet; it is preferably less than 0.04 weight percent. Based on the above process, the following processes are sulfur (S) and inscription (A1). The weight percentage of the steel billet is 70% ~ 90% when the temperature is above the low point. When drawing deep-drawn cold-rolled steel sheet, it will be carbon (C), silicon (si), manganese (Mn), phosphorus (p),

&gt; IUN)、單獨添加的鈦（Ti)或鈮依前述之 貫質之鐵與不顯著之雜質，經造塊或連鑄 於1 200 °C進行鋼胚再加熱，並在高於Ar3 成熱札’且同時在低於7 6 〇它做盤捲，而 軋，冷軋後，並採以連續退火處理，而連 $ 1¾ &amp;再結晶溫度’ 一般為700 °c〜850 °c 554047&gt; IUN), separately added titanium (Ti) or niobium according to the aforementioned consistent iron and insignificant impurities, re-heated the steel billet by block making or continuous casting at 1 200 ° C, and It is' hot rolled 'and at the same time it is coiled below 7 6 0, and rolled and cold rolled, and then subjected to continuous annealing treatment, and even $ 1¾ &amp; recrystallization temperature' is generally 700 ° c ~ 850 ° c 554047

本發明製程條件之理由： (一） 本發明鋼胚再加熱溫度（SRT)需低於1 200 °C ;鋼胚再 加熱溫度（SRT)若高於1 2 0 0 °C，則TiC析出物固溶回基 地’熱軋冷卻時，TiC不易與TiS形成Ti4C2S2，而會 幵二成T i C祕細析出物，鋼片冷軋退火時會阻擔丨111 }再 結晶集合組織的成長而降低鋼片成形性，且熱軋冷名 寺因固/谷石反析出驅動力大，晶界不易保有固貧^ 強化，因而抗二次加工脆化之能力變差。 /反來 (二） 本發明熱軋時完軋溫度需高於Ar3點以上；若$ 低於Ar 3點，則表面容易形成{丨丨〇 }應變集合組二，L時 札退火後，{ 111 }再結晶集合組織不易成長二冷 片成形性。 ^降低鋼 (二）本發明鋼經上述熱軋後，再經冷軋及連續返火即 · 冷軋及退火條件並不必刻意限制，但是冷桌丨可’ ^乳平通常母 定在40〜95%之間，一般以70%〜90%為佳，而連續、： &gt;JBL度最少應南於再結晶溫度’但也不可太其、、西' 、、 呵〉凰，-船 以70(TC〜85 0 °C之間為宜。 (四）冷軋退火後之鋼片，可以做鍍鋅、鍍錫或錢絡等各 後續鍍面處理；又，退火後，最好實施〇.4%〜9 ^ 1 U % 冷 軋率之調質軋延，將鋼片整平；除此之外，；^ 也可以做 防銹處理等必須措施。 為了進一步說明本發明鋼之優異性，下列會A η 私1 丨〜見她例之比 較可做說明：Reasons for the process conditions of the present invention: (1) The reheating temperature (SRT) of the steel billet of the present invention needs to be lower than 1 200 ° C; if the reheating temperature (SRT) of the steel billet is higher than 12 0 ° C, the TiC precipitates When solid solution is returned to the base, during hot rolling and cooling, TiC is not easy to form Ti4C2S2 with TiS, but it will form Ti iC precipitates, which will hinder the growth of the recrystallized aggregate structure during the cold rolling annealing of steel sheet. Steel sheet formability, and the hot rolling cold Mingsi has a strong driving force for solid / valley reverse precipitation, and the grain boundary is not easy to maintain solid and poor ^ strengthening, so the ability to resist secondary processing embrittlement becomes poor. / Conversely (2) The hot rolling temperature of the present invention needs to be higher than Ar3 point; if $ is lower than Ar 3 point, the surface is easy to form {丨 丨 〇} strain set group 2. After annealing at L hour, { 111} The recrystallized aggregate structure is not easy to grow. ^ Reduced steel (II) After the above-mentioned hot rolling of the steel of the present invention, and then cold rolling and continuous tempering, the conditions of cold rolling and annealing do not need to be intentionally limited, but the cold table 丨 can be '^ milk level is usually set at 40 ~ 95%, generally 70% ~ 90% is better, and continuous, &gt; JBL degree should be at least south of the recrystallization temperature 'but not too high, west' ,, hu >>, boat to 70 (TC ~ 85 0 ° C is suitable. (4) steel sheet after cold-rolled annealing can be galvanized, tin-plated or Qianluo and other subsequent plating surface treatment; and, after annealing, it is best to perform 〇. 4% ~ 9 ^ 1 U% quenched and tempered at a cold rolling rate to flatten the steel sheet; in addition, ^ can also do necessary measures such as rust prevention treatment. In order to further illustrate the superiority of the steel of the present invention, The following meeting A η 私 1 丨 ~ can be explained by comparison with her example:

請參閱表一係顯示鋼之化學成份（重量百分 -------^比）、鋼胚Please refer to Table 1 for the chemical composition of steel (weight percentage ------- ^ ratio), steel embryo

554047 案號 89113127 曰 修正 五、發明說明（10) 再加熱溫度（SRT)、盤捲溫度（CT)、r值及轉脆溫度等之關 係表，而該表一所示之A(A1、A2)、B(B1、B2、B3)、C、D 、E'F、G、H、I九種鋼種其組成物中石夕（Si)的重量百分 比為0·001〜0·02，猛（Μη)的重量百分比為〇·15〜0.25，磷 (Ρ)的重量百分比為〇·〇1〜0·02，另外，於表一中的C鋼種 又添加0.01重量百分比的鈮（Nb)，同時，該九種鋼種乃經 一般熔煉後鑄成鋼胚，再於鋼胚再加熱溫度（SRT)為1250 C、1 1 5 0 °C或1 〇 5 0 °C之爐中保持1小時熱軋軋成3 · 2 mm後之 熱軋板，完軋溫度約9 1 0 °C，空冷後再置於盤捲溫度（C T) 為65 0 °C、70 0 °C或75(TC爐中保溫2小時，爐冷後以模擬 盤捲處理；酸洗後，冷軋成0· 8 mm之鋼片（冷軋裁減率7 5%) ;鋼片沿軋延方向0度，45度，90度方向切成30 mm X 25 0 mm 之試片（拉伸試驗用）或切成1 1 0 mm X 2 2 0腿（轉脆溫度測量 用）之試片，再做一般之連續退火處理，而連續退火處理 的方法乃是急速加熱至8 5 0 °C，保溫6 0秒後再空冷，再經 0 · 5 %冷札率之调質札延，其中’ A1鋼、A 2鋼係表示其分別 於1 05 0 °C、1250°C之鋼胚再加熱溫度（SRT)後，其R值分別 為2· 1 1、1· 95，轉脆溫度-60 °C、-40 °C，B1 鋼、B2 鋼、B3 鋼 、、田 /凰 係表示其分別於1150 °C、1 250 °C及1150 °C之鋼胚再加熱 度（SRT)，再經6 50 °C、75(TC及75 0 °C之盤捲溫度（CT)後 其R值分別為2· 2、1· 97及2. 26，轉脆溫度-60 °C、-40554047 Case No. 89113127 Amendment V. Description of the invention (10) Relation table of reheating temperature (SRT), coiling temperature (CT), r value, and brittleness temperature, etc., and A (A1, A2 ), B (B1, B2, B3), C, D, E'F, G, H, I. The weight percentage of Shi Xi (Si) in its composition is from 0.001 to 0.02. ) The weight percentage is 0.15 to 0.25, and the phosphorus (P) weight percentage is 0.001 to 0.02. In addition, 0.01% by weight of niobium (Nb) is added to the steel type C in Table 1, and at the same time, The nine types of steel are cast into steel slabs after general melting, and then hot rolled for 1 hour in a furnace with a steel slab reheating temperature (SRT) of 1250 C, 1 150 ° C, or 1050 ° C. After hot rolling of 3 · 2 mm, the rolling temperature is about 9 1 0 ° C. After air cooling, the coil is placed at a coil temperature (CT) of 65 0 ° C, 70 0 ° C, or 75 (in the TC furnace to maintain 2 Hours, after the furnace is cold, the coil is treated by simulation; after pickling, it is cold rolled into a steel sheet of 0 · 8 mm (cold rolling reduction rate of 75%); the steel sheet is rolled in the direction of 0 °, 45 °, and 90 ° Cut into 30 mm X 25 0 mm test pieces (for tensile test) or cut into 110 mm X 2 The 20-leg (for brittle temperature measurement) test piece is then subjected to ordinary continuous annealing treatment, and the continuous annealing method is to rapidly heat to 850 ° C, hold for 60 seconds, and then air-cooled, and then 0 · Quenching and tempering with a cooling rate of 5%, where 'A1 and A2 steels represent their reheating temperatures (SRT) at 1 05 0 ° C and 1250 ° C, respectively, and their R values are 2 · 1 1,1 · 95, transition brittle temperature -60 ° C, -40 ° C, B1 steel, B2 steel, B3 steel, Tian / Phoenix indicate that they are at 1150 ° C, 1 250 ° C and 1150 The reheating degree (SRT) of the steel billet at ° C, after the coiling temperature (CT) of 6 50 ° C, 75 (TC and 75 0 ° C), the R values are 2 · 2, 1.97, and 2. 26, turning brittle temperature -60 ° C, -40

〇C 及-60 〇C 績請參閱表一可知，D、E、F及I等四鋼種，化學成份 合乎1^*&gt;(4 8/12)\(：及(：&lt;(12/32)\8等兩方程式所設定 條件’因此其成份落入第一圖所示之第U區或第皿區；〇C and -60 〇 Please refer to Table 1 to know that the chemical composition of D, E, F and I and other four steels conforms to 1 ^ * &gt; (4 8/12) \ (: and (: &lt; (12 / 32) The conditions set by the two equations, such as \ 8, therefore fall into the Uth or Dish area shown in the first figure;

不 之 554047 _案號89113127__年月 _曰 你π：__ 五、發明說明（11) 即使有些鋼料轉脆溫度低於-50 °C，但所有鋼料r值均小於 2 · 0，不合乎本發明設定之目標值而列為比較例；反觀A j 、B1、C、G及Η等五鋼種，化學成份全合乎Ti*&gt;(48/12)x C及C&lt;(12/32)XS等兩方程式所設定之基本條件；然仔細 看A2鋼，當SRT為1 250 °C 時（高於鋼胚再加熱溫度（SRT )需 低於1200 °C之設定），r值為1.95 、轉脆溫度為-40°C，雙 雙不合乎本發明設定之目標值而列為比較例，顯示鋼胚再 加熱溫度（SRT)需低於1 2 00 °C之重要性。 再觀B1、B3鋼，當SRT為1150°C時，不管CT為650 °C戈 750 °C，其r值均大於2·0，且轉脆溫度均低於-5(pc，合乎 本發明設定之目標值；顯示CT只要低於76 0 °C，而其他條 件合乎本發明之設定，則鋼片性質可達到本發明設定之目 標值；B2鋼也顯示，當SRT為1250 °C時，r值只有1·97、轉 脆溫度為-4 0 °C，雙雙不合乎本發明設定之目標值而列為 比較例，此例再度證實鋼胚鋼胚再加熱溫度（sRT)需低於 1 2 0 0 °C之重要性。 仍請參閱表一，C鋼種化學成份全合乎Ti*&gt;(48/12)&gt;&lt; C及f&lt;( 12/32) XS等兩方程式所設定之條件，製程也合乎 °又疋之條件’雖然另外添加0 · 〇 1重量百分比之銳（N b )，r 值及轉脆溫度均合乎本發明設定之目標值而列為發明鋼， 可見丰發明除單獨添加鈦（τ丨）外，也可複合添加鈦（τ丨）及 鈮（Nb)。 又請參閱表一，G鋼化學成份合乎1^*&gt;(48/12)&gt;&lt;(：及 C&lt; (12/32) XS等兩方程式所設定之條件，製程也合乎設定 之—條# ’ Y旦g) !太含量超過0·ΐ〇重量百分比之規定，因此雖不 之 554047 _ Case No. 89113127__Year Month _ said you π: __ V. Description of the invention (11) Even if some steel materials become brittle below -50 ° C, all steel materials have r values less than 2 · 0, no In accordance with the target value set by the present invention, it is listed as a comparative example. In contrast, the five steel types, such as A j, B1, C, G, and rhenium, all have chemical compositions that meet Ti * &gt; (48/12) x C and C &lt; (12/32 ) The basic conditions set by the two equations such as XS; but look closely at the A2 steel. When the SRT is 1 250 ° C (higher than the steel reheating temperature (SRT) needs to be lower than the setting of 1200 ° C), the r value is 1.95 The brittle temperature is -40 ° C, both of which are not in accordance with the target value set by the present invention and are listed as comparative examples, showing the importance of the steel reheating temperature (SRT) to be lower than 1 200 ° C. Looking again at the B1 and B3 steels, when the SRT is 1150 ° C, no matter the CT is 650 ° C or 750 ° C, the r values are greater than 2.0, and the transition embrittlement temperatures are lower than -5 (pc, consistent with the present invention The set target value; as long as the displayed CT is below 76 0 ° C, and other conditions are in accordance with the setting of the present invention, the properties of the steel sheet can reach the set value of the present invention; B2 steel also shows that when the SRT is 1250 ° C, The r value is only 1.97, and the brittle temperature is -40 ° C. Both are not in accordance with the target value set by the present invention and are listed as comparative examples. This example once again confirms that the reheating temperature (sRT) of the steel billet needs to be lower than 1 The importance of 2 0 ° C. Please also refer to Table 1. The chemical composition of steel C is in accordance with Ti * &gt; (48/12) &gt; &lt; C and f &lt; (12/32) XS. The conditions and processes are also in accordance with the conditions of °° and 疋. 'Although the addition of 0 · 001 weight percent sharp (N b), the r value and the brittle temperature are in line with the target value set by the present invention and are listed as the invention steel. In addition to adding titanium (τ 丨) separately, titanium (τ 丨) and niobium (Nb) can also be added in combination. See also Table 1. The chemical composition of G steel conforms to 1 ^ * &gt; (48/12) &gt; &lt; ( And C &lt; Condition (12/32) XS like set of two equations, the process is also desirable to set the - Article # 'Y denier g) too content exceeds 0.5 wt% of a predetermined ΐ〇, although so!

圓 554047 案號 _ 8911ΓΠ9了 五、發明說明（12) 年 修正 ^值超過2.0 ’但轉脆 又之目標值而列為士 “ ^ ’不合乎本發明設 方程式所設定4:::例合須合上述之兩 \鋼化學成份及製程均合乎設定之條件义 乎本發明設定之目標值而列為發明鋼。值及轉脆-度-Yuan 554047 Case number _ 8911ΓΠ9 V. Explanation of the invention (12) The year of correction ^ value exceeds 2.0 ', but the target value becomes more brittle and it is listed as a "^" which is not in accordance with the present invention and is set by the equation 4 ::: The above two steel chemical compositions and manufacturing processes are in accordance with the set conditions and the target values set by the present invention are listed as the invention steel. Value and brittleness-degree-

，上所述，本發明超深衝性且具抗：次加卫脆性之冷 軋鋼片組成物，確實可由其化學成份及製程，達到具有r 值大於2 · 0，轉脆溫度低於-6 G °c且成形性佳之功效，是以 本發明誠為一進步之設計，又未見有相同或近似之物品揭 露於市，爰依法提出專利申請。 惟’以上所述者，僅係本發明之較佳實施例而已，故 舉凡應用本發明說明書及申請專利範圍所為之等效變化， 理應包含在本發明之專利範圍内。As mentioned above, the cold-rolled steel sheet composition with ultra-deep drawability and resistance to secondary infringement of the present invention can indeed be achieved by its chemical composition and process to have an r-value greater than 2 · 0, and its brittle temperature below -6 The effect of G ° c and good formability is based on the design of the present invention, and no identical or similar items have been disclosed in the market, and a patent application has been filed according to law. However, those mentioned above are only the preferred embodiments of the present invention, and any equivalent changes made by applying the description of the present invention and the scope of patent application should be included in the patent scope of the present invention.

第16頁 554047 案號 89113127 年 月 曰 修正 圖式簡單說明 第一圖係本發明之合金成份設定範圍圖。 表一係本發明鋼、化學成份（重量百分比）、鋼胚再加 熱溫度（SRT)盤捲溫度（CT)與r值及轉脆溫度之關係表。Page 16 554047 Case No. 89113127 Modification Brief Description of the Drawings The first picture is a set range diagram of the alloy composition of the present invention. Table 1 is a table showing the relationship between the steel of the present invention, chemical composition (weight percentage), reheating temperature (SRT) coil temperature (CT), r value, and brittleness temperature.

第17頁Page 17

Claims (1)

554047554047 Λ____1. 曰Λ ____ 1. - J超深衝性且具抗二次加工脆組成物 /、組成物至少包含有0.001〜〇〇〇6重晋石八 / η \ η 里曰刀t匕之碳 (^) ’0.001〜〇·1重量百分比之矽（Si)，〇〇〇1〜0.5重 量百分比之錳（Μη)，0· 00卜0· 02重量百分比之鱗·（ρ) ^0· 〇〇1〜0. 02重量百分比之硫（S)，0· 〇i〜〇· ! ^量百 为比之I呂（A1)，〇·〇〇1〜0.006重量百分比之氮（N)，單 獨添加的〇· (Π〜〇· 1重量百分比之鈦（Ti)，以及實質之 鐵與不顯著之雜質等成份；同時，上述合金成份需滿 足丁丨*&gt;(48/12)\(：及(：&lt;(12/32)\3等兩方程式（所有 元素均以重量百分比表示，而48、12、14、32分別為 Tl、C、N、S之原子量，其中，Ti* = Ti - 3.42XN -1.5 x I);另外，再將該等組成物混合後，經造塊或連鑄 所知之鋼胚在低於1200 °C進行鋼胚再加熱，並在高於 A r 3點以上之溫度完成熱軋，且同時在低於μ 〇艽做盤 捲’而在高於70%冷軋率冷軋後在結晶溫度7〇〇 t以上 做連續退火處理而獲得超深衝性且具抗二次加工脆性 之冷軋鋼片組成物，其深衝比大於2 · 〇，而轉脆溫度 小於-6 0 °C。 2 依據申請專利範圍第1項所述超深衝性且具抗二次加 工跪性之冷軋鋼片組成物，其中，該超深衝性且具抗 二次加工脆性之冷軋鋼片組成物可在其組成物中複合 添加〇· 0 0 5〜0· 04重量百分比之鈮者。-J ultra deep drawability and resistance to secondary processing brittle composition /, the composition contains at least 0.001 ~ 〇006 heavy Jin Shiba / η \ η said the knife t dagger carbon (^) '0.001 ~ 〇 · 1 weight percent of silicon (Si), 0.0001 ~ 0.5 weight percent of manganese (Μη), 0 · 00 bu 0 · 02 weight percent of scale · (ρ) ^ 0 · 〇〇1 ~ 0. 02 weight Percent of sulfur (S), 0 · 〇i ~ 〇 ·! ^ The amount of percentage is I Lu (A1), 0.001 ~ 0.006 weight percent of nitrogen (N), separately added 〇 (Π ~ 〇 · 1% by weight of titanium (Ti), and substantial iron and insignificant impurities; meanwhile, the above alloy composition must meet the requirements of Ding ** (48/12) \ (: and (: &lt; (12 / 32) \ 3 and other two equations (all elements are expressed by weight percentage, and 48, 12, 14, 32 are the atomic weights of Tl, C, N, and S, respectively, where Ti * = Ti-3.42XN -1.5 x I ); In addition, after mixing these components, the steel slab known by agglomeration or continuous casting is reheated at a temperature below 1200 ° C, and hot rolling is completed at a temperature higher than A r 3 points And at the same time do coiling below μ 〇 艽 'and More than 70% cold rolling rate After cold rolling, continuous annealing treatment is performed at a crystallization temperature of more than 700t to obtain a cold-rolled steel sheet composition with ultra-deep drawability and resistance to secondary processing embrittlement. The deep-draw ratio is greater than 2. And the brittle temperature is less than -6 0 ° C. 2 According to the cold-rolled steel sheet composition with ultra-deep drawing property and resistance to secondary processing kneeling as described in item 1 of the scope of patent application, the ultra-deep drawing property A cold-rolled steel sheet composition resistant to secondary processing embrittlement may be compounded by adding 0.05 to 0.05% by weight of niobium in the composition. 第18頁 554047Page 18 554047 C « 第Θ頁C «page Θ