汽車車門外板沖壓模具設(shè)計(jì)【全套含CAD圖紙】

喜歡這套資料就充值下載吧。資源目錄里展示的都可在線預(yù)覽哦。下載后都有，請放心下載，文件全都包含在內(nèi)，有疑問咨詢QQ:1064457796 INTERNATIONAL JOURNAL OF PRECISION ENGINEERING AND MANUFACTURING Vol. 13, No. 7, pp. 1101-1106 JULY 2012 / 1101 DOI: 10.1007/s12541-012-0144-x NOMENCLATURE R m = tensile strength A 11.3 = percentage elongation 1. Introduction Light weight auto-body and passive safety of passengers become trend of automotive industry, while energy saving and environment protecting deeply wised. Application of ultra-high strength steel with dual advantages of weight-light and safety improvement performance grows rapidly, also with characteristics of both high-strength and high-precision, has become a industry hotspot. On one hand, the forming process parameters are the key points of hot stamping technology, on the other hand, hot stamping die needs to set cooling system to ensure the die function of stamping and quenching, which is quite different from the common stamping mold. The main parameters including heating temperature, holding time, forming speed, impulse pressure, holding time, open mold temperature, flow velocity and etc., should be optimized during hot stamping process primarily for guaranteed high-intensity and high- precision of forming parts. Taking a Chinese independent brand car door beam as an example, ultra-high strength steel hot stamping technology and lightweight design were studied in this paper. 1-3 2. Development of hot stamping die for ultra-high strength steel door beam 2.1 Material optimization of hot stamping die During hot stamping process, phase transformation strengthening of parts after forming is completed through the dies, so the dies require creation of cooling pipes inside to realize a cooling quenching function. 4,5 From the point of view for material properties, die material must have high thermal conductivity coefficient in order to achieve rapid and uniform cooling effect, better thermal fatigue performance and high heat strength to work under long-term alternation of heating and cooling state, strong wear-resistance to bear thermal friction of high temperature blank and its oxidation skin. 6-8 Hot working die steel material of HHD containing high chromium in the composition (shown in Table 1) to enhance its corrosion-resistance was used. Under normal temperature, the Hot Stamping Die Design for Vehicle Door Beams using Ultra-High Strength Steel Chao Jiang 1 , Zhongde Shan 1,# , Bailiang Zhuang 1 , Milan Zhang 1 , and Ying Xu 1 1 State Key Lab. of Advanced Forming Technology with increasing of pipe diameter, the average cooling rate linearly increases. And the greatest influence factor on cooling effectiveness is depth of pipe from the surface, followed by pipe spacing, and finally pipe diameter, that is, calculative determination of depth from die surface to cooling pipe should be considered first during design of die cooling system, and it is also the basis of the reasonable design of pipe spacing and pipe diameter. The depth from die surface to cooling pipe of 10mm, pipe spacing of 15mm and pipe diameter of 10mm was the optimized result of the simulation. The design of cooling pipe should make sure that the die could keep ensuring sufficient strength during hot stamping process, so the overall strength intensity of the die needs to be checked firstly. The next numerical simulation boundary conditions were as friction coefficient of 0.03, forming speed of 50mm/s, the stress field and force were shown in Fig. 4. The results showed that there was no damage on die because the maximum deformation was only 0.027mm, which was in the elastic deformation range. The stress simulation results showed that the stress is far less Table 1 Composition of HHD (wt-%) C Cr Mo Ni V W Si Mn 0.20.35 8.013.0 1.02.0 0.71.3 0.41.0 0.31.0 0.71.3 0.21.0 Fig. 1 Door beam Fig. 2 Internal cooling pipes Table 2 Parameters of cooling pipe Depth from die surface to cooling pipe(mm) 5 10 15 20 25 Spacing between pipes (mm) 15 20 25 30 35 Dia. of cooling pipe (mm) 10 12 15 17 20 0 5 10 15 20 25 30 32.8 29.6 27.2 26.6 25.6 average cooling rare (/s) pip e de pth ( m m ) 10 15 20 25 30 35 40 p i p e ap ac e (mm ) Fig. 3 Influence of cooling parameters pipe depth: r=0.97 pipe space: r=0.98 INTERNATIONAL JOURNAL OF PRECISION ENGINEERING AND MANUFACTURING Vol. 13, No. 7 JULY 2012 / 1103 than that of the blank mechanical strength, cracking phenomena would not happen. The corresponding door beam die entities was shown in Fig. 5. 3. Hot stamping process applications 3.1 Hot stamping simulation Hot stamping process mainly concerns on high temperature deformation behavior of sheet, which is closely related to optimization of process parameters. In this paper, Baosteel hot- rolled BR1500HS (compositions shown in Table 3), with hardness of HV193, tensile strength of 666MPa, microstructure of ferrite and pearlite was in experimental measurement. From CCT curve (Fig. 6), it could be seen that, AC 3 was 811, AC 1 was 736, critical cooling rate of 15/s, martensite start point was between the 350380, the end point of was of 280300 . Experiments were conducted using Gleeble-3800 thermal simulator to study the rheological behavior. Sample part was heated to 950 under 15/s speed, persevered at this temperature for 5 minutes to obtain homogeneous austenite organization, then quickly cooled to experiment temperature under speed of 70/s to complete isothermal tension test. During process of data analysis, Norton-Hoffs law was used to build the models: ( ) 0.31 0.07 50.12 exp 2542 T= when keeping the length and the width dimension constant, while reducing the depth from 32 mm to 23.6 mm, weight of the beam decreased 9.32%, all led to energy conservation and emission reduction. Three-point bending experiments of door beams (Fig. 14) showed that, with the reduction of sheet thickness or the reduction of depth, bending property of hot stamping beam reduced synchronously, and thickness of sheet metal played less important role on the bending property, so automotive parts could achieve more lightweight from thinning thickness while achieving weight loss purpose. As shown as Fig. 14, the deformation of lightweight optimization door beam increases 15mm compared to 2mm that of thick 32mm deep door beam, 6.7% of the original deformation, the deformation increasing amount would have no effect on the automotive side impact test results, that was, the improved lightweight door beams satisfied double requirements of safety and lightweight. 13 4. Conclusions (1) The most influential factor on cooling effectiveness of pipe is depth of pipe from die forming surface, followed by pipe spacing and pipe diameter. Depth from die surface to cooling pipe should be basis of reasonable design of pipeline spacing and diameter. (2) Hot stamping die developed with optimized system and process parameters could guarantee full martensite microstructure and excellent mechanical performance, with average tensile strength of 1550Mpa, elongation of 6.5%, shape accuracy of 0.5mm; and the optimization process parameters were heating temperature of 930 , holding time of 4.5min, forming speed of 75mm/s, punching pressure of 7MPa, quenching time of 15s, flow velocity of 1.1m/s. (3) The ultra-high strength steel door beam was optimized to realize crash test full marks, with stiffness increased of 2.5 times, strength increased of 3.8 times, lightweight of 9.32% than that of original pipe, which achieved dual objectives of security and lightweight. ACKNOWLEDGEMENT This study was supported by a grant from National Basic Research Program of China (2012CB724301), Program of International S&T Cooperation (2011DFA50810). REFERENCES 1. 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Manuf., Vol. 10, No. 2, pp. 117-126, 2009. 0 2000 4000 6000 8000 10000 12000 14000 16000 0 102030405060 Displacement (mm) F o r ce （ N ） Fig. 14 Three-point bending test comparison curves of 4 kinds of door beam 2mm thickness with depth of 32mm 1.6mm thickness with depth of 32mm 1.6mm thickness with depth of2 5mm cold bending pipe 1106 / JULY 2012 INTERNATIONAL JOURNAL OF PRECISION ENGINEERING AND MANUFACTURING Vol. 13, No. 7 12. Park, C. W., Kwon, K. S., Kim, W. B., Min, B. K., Park, S. J., Sung, I. H., Yoon, Y. S., Lee, K. S., Lee, J. H., and Seok, J., “Energy Consumption Reduction Technology in Manufacturing - A Selective Review of Policies, Standards, and Research,” Int. J. Precis. Eng. Manuf., Vol. 10, No. 5, pp. 151-173, 2009. 任 務(wù) 書課題名稱： 汽車車門外板 沖壓模具設(shè)計(jì) 課題名稱汽車車門外板沖壓模具設(shè)計(jì)主要內(nèi)容(包括設(shè)計(jì)參數(shù))與要求一、本設(shè)計(jì)的主要內(nèi)容：汽車車門屬大型汽車覆蓋件，通常采用冷沖壓的方式加工而成。本次設(shè)計(jì)題目即為汽車車門沖壓模具結(jié)構(gòu)設(shè)計(jì)，設(shè)計(jì)者可以參考任一款車型的轎車車門，進(jìn)行產(chǎn)品結(jié)構(gòu)設(shè)計(jì)和模具結(jié)構(gòu)設(shè)計(jì)，要求完成以下幾項(xiàng)工作：1、 完成該沖壓模具結(jié)構(gòu)設(shè)計(jì)與計(jì)算，并完成設(shè)計(jì)說明書。2、 完成過程材料的編寫，包括工作計(jì)劃、開題報(bào)告、讀書報(bào)告、外文翻譯、階段總結(jié)、工作總結(jié)和工作記錄本等。3、用CAD相關(guān)軟件完成三維車門結(jié)構(gòu)繪制，完成三維模具結(jié)構(gòu)設(shè)計(jì)，可將部分三維圖片插入畢業(yè)設(shè)計(jì)說明書中。4、用AutoCAD軟件進(jìn)行沖壓模具的二維結(jié)構(gòu)圖繪制，要求畫出模具總裝圖1張以及主要結(jié)構(gòu)零件圖3張。二、畢業(yè)設(shè)計(jì)基本要求：（1） 畢業(yè)論文應(yīng)符合高校畢業(yè)生的畢業(yè)論文格式、內(nèi)容要求規(guī)范，論文應(yīng)包括選題的研究或者開發(fā)意義，技術(shù)理論綜述，系統(tǒng)架構(gòu)和研究結(jié)果展示以及分析評價(jià)等。（2） 設(shè)計(jì)說明書應(yīng)有計(jì)算分析數(shù)據(jù)，并保證數(shù)據(jù)真實(shí)可信，字?jǐn)?shù)達(dá)到1萬字。（3） 完成時(shí)間嚴(yán)格按照學(xué)院要求執(zhí)行；（4） 設(shè)計(jì)文件在答辯完成后進(jìn)行裝訂；（5） 設(shè)計(jì)文件電子文稿和打印文稿一并上交；（6） 設(shè)計(jì)文件嚴(yán)禁雇人代做、抄襲，一旦發(fā)現(xiàn)，無畢業(yè)設(shè)計(jì)成績；（7） 時(shí)間要求在 年 月中旬前完成。工 作 進(jìn) 程 及 需 完 成 工 作 量1、開題論證階段：查找資料，確定畢業(yè)設(shè)計(jì)實(shí)施方案。 2周（共2周）2、分析、研究、設(shè)計(jì)、實(shí)施、報(bào)告編寫階段。 311周（共9周）3、論文審核修改階段：指導(dǎo)教師審閱論文，提出修改意見，學(xué)生編輯修論文，學(xué)生論文打印稿經(jīng)指導(dǎo)老師評定之后交給評閱教師評閱。 1214周（共3周）4、畢業(yè)答辯階段： 15周（共1周）5、畢業(yè)設(shè)計(jì)工作總結(jié)階段。 1617周（共2周)應(yīng) 遵 守 的 法 紀(jì) 法 規(guī)1、 國家和實(shí)習(xí)所在地的政府機(jī)關(guān)的各種法律、法規(guī)；2、 學(xué)校和實(shí)習(xí)單位的規(guī)章制度；3、 校紀(jì)校規(guī)；4、 實(shí)習(xí)法律；5、 保護(hù)知識產(chǎn)權(quán)；畢業(yè)設(shè)計(jì)(論文)完成日期： 年 月 日指導(dǎo)教師： (簽字)教研室主任： (簽字)譯文：利用超高強(qiáng)度鋼設(shè)計(jì)車門橫梁熱沖壓模具 摘要：節(jié)能與安全是汽車行業(yè)發(fā)展的永恒主題。熱沖壓超高強(qiáng)度鋼擁有在減少車輛重量的同時(shí)提高安全性能這一雙重優(yōu)點(diǎn)，使其被廣泛地應(yīng)用于汽車車身結(jié)構(gòu)設(shè)計(jì)中。本文以車門橫梁作為例子對成形和淬火一體化模進(jìn)行了研究，尤其是整個(gè)模具結(jié)構(gòu)和熱沖壓過程的研究，通過數(shù)值模擬對凹模強(qiáng)度、冷卻管布置和其他相關(guān)因素進(jìn)行了優(yōu)化，并且用該模具生產(chǎn)出了拉伸強(qiáng)度為1550Mpa，伸長率為6.5和形狀精度為0.3mm的橫梁。此外，橫梁的剛度和強(qiáng)度比原來的分別提高了2.2倍和3.8倍，在C-NCAP碰撞測試中得到了滿分。通過減小橫截面的厚度和拉深深度，橫梁的重量減輕了9.32，并且提高了節(jié)能和減排效果。關(guān)鍵詞：熱成形，超高強(qiáng)度鋼，機(jī)械特性，汽車輕量化71 引言視曲梁enfan汽車輕量化和乘客的被動(dòng)安全性能成為汽車行業(yè)的發(fā)展趨勢，而節(jié)能環(huán)保被大家深深地重視。超高強(qiáng)度鋼具有重量輕和安全改進(jìn)的性能這一雙重優(yōu)勢使得它的應(yīng)用得到迅速增長，也正是由于高強(qiáng)度和高精度這兩個(gè)特點(diǎn)，使其已成為行業(yè)的熱點(diǎn)。一方面，在成形過程中的參數(shù)是熱沖壓技術(shù)的關(guān)鍵點(diǎn)，另一方面，熱沖壓模具需要設(shè)置冷卻系統(tǒng)以確保沖壓和淬火，這是和普通沖壓模具完全不同的功能。主要參數(shù)包括加熱溫度，保溫時(shí)間，成型速度，沖裁力，開模溫度，流速等，在熱沖壓工藝中主要是為了確保對成型零件的高強(qiáng)度和高精度進(jìn)行優(yōu)化。本文以一個(gè)中國自主品牌的車門橫梁為例，對超高強(qiáng)度鋼板熱沖壓技術(shù)和輕量化設(shè)計(jì)進(jìn)行了研究。2 超高強(qiáng)度鋼車門橫梁的熱沖壓模具的開發(fā)2.1熱沖壓模具材料的優(yōu)化在熱沖壓過程中，相變強(qiáng)化零件成形后通過模具完成，所以模具需要建立內(nèi)部冷卻管道，以實(shí)現(xiàn)冷卻淬火的功能。從材料性能的角度來看，模具材料必須具有較高的導(dǎo)熱系數(shù)，以達(dá)到快速均勻的散熱效果，更好的熱疲勞性能和耐高溫性長期地在冷熱交替的狀態(tài)下工作，需要有好的耐磨性承受劇烈的摩擦和高溫，抵抗坯料表面的氧化。HHD是高鉻含量的熱作模具鋼材料（表1中示出），鉻在使用中可以提高其耐腐蝕性。常溫下，HHD的硬度在HRC48以上，在600可以保持HV498.2，在高溫下顯示出較高的強(qiáng)度和良好的熱穩(wěn)定性。該材料在高溫下還顯示出優(yōu)異的耐磨性，是ASSAB8407材料的三分之一。2.2 超高強(qiáng)度鋼橫梁的發(fā)展和沖壓模具冷卻系統(tǒng)管狀梁是橫梁的一種，它包括無縫管橫梁和焊縫管橫梁，其中焊縫管是由最大拉伸強(qiáng)度約為400MPa焊接鋼板彎曲成管狀制成的，無縫鋼管是用拉伸強(qiáng)度高達(dá)600MPa的材料通過拉伸方法制造的，極少的硬化管得到1400MPa的拉伸強(qiáng)度。這些橫梁具有結(jié)構(gòu)簡單，制造成本低優(yōu)點(diǎn)，但是其防護(hù)性能相對較差。另一種防撞門梁被稱為帽形梁主要?jiǎng)澐殖蓡蚊睜睿║型）和雙帽狀（W型），其拉伸強(qiáng)度可達(dá)1500MPa以上，并通過燙印工藝獲得更高的安全性能，其多應(yīng)用于歐洲和美國的汽車上。一種橫梁從無縫管優(yōu)化成雙帽狀（厚2毫米，長1071毫米和寬99.9毫米）與圖1所示。冷卻管道被布置成均勻分布以維持良好的冷卻效率，如圖2所示，螺栓密封方法用于上模頭和O形密封環(huán)的端部被用在底部，以防止高速冷卻水循環(huán)泄漏。冷卻速度是由水的流速保證的，根據(jù)生產(chǎn)周期進(jìn)行調(diào)節(jié)，并且選擇合適的冷卻水的溫度。2.3 冷卻參數(shù)設(shè)計(jì)熱沖壓模具的冷卻系統(tǒng)不僅影響完成成形和淬火，而且還影響零件的最終性能。這些參數(shù)包括，例如三個(gè)方面從模具表面至冷卻管道深處，管道之間的間距（管中心的距離）和冷卻管的直徑，即位置、布局和管形狀。先決條件數(shù)值模擬模具的初始溫度為20，坯料初始溫度為890，冷卻水的流速為1m/ s，其他冷卻參數(shù)都列于表2模擬結(jié)果如圖3所示。如圖3所示，從模具表面至冷卻管中心隨著距離的增加和管道間距離的增加，平均冷卻速率減小;隨著管道直徑的增加，平均冷卻速度線性增加。對冷卻速度影響最大的因素是離模具表面的距離，其次是管道間距，最后是管道的直徑。也就是說，設(shè)計(jì)模具冷卻系統(tǒng)中首先要考慮的是從模具表面到冷卻管的距離的計(jì)算，并且它還是管道間距和管道直徑設(shè)計(jì)的合理與否的基礎(chǔ)。到模具表面的距離為10mm的散熱管，15mm的管道間距和10mm的管道直徑是最優(yōu)的仿真結(jié)果。冷卻管道的設(shè)計(jì)應(yīng)保證模具能達(dá)到熱沖壓工藝所需要的足夠的強(qiáng)度，因此需要進(jìn)行模具初步的整體強(qiáng)度的測試。下一數(shù)值模擬的邊界條件是摩擦系數(shù)為0.03，成形速度為50mm/ s，應(yīng)力場和應(yīng)力在圖4中示出。結(jié)果表明，模具沒有損壞，因?yàn)槠渥畲笞冃蝺H為0.027毫米，這是在彈性變形范圍內(nèi)。應(yīng)力的仿真結(jié)果表明，該應(yīng)力是遠(yuǎn)遠(yuǎn)沒有超過該坯料的機(jī)械強(qiáng)度，開裂現(xiàn)象就不會(huì)發(fā)生。相應(yīng)的橫梁模具實(shí)體如圖5所示。3 熱沖壓工藝的應(yīng)用3.1 熱沖壓仿真熱沖壓工藝主要是對板材的高溫變形行為進(jìn)行分析，對與其密切相關(guān)的工藝參數(shù)進(jìn)行優(yōu)化。在本文中，寶鋼熱軋BR1500HS（表3中所示的組合物）具有HV193的硬度和666MPa的拉伸強(qiáng)度，鐵素體和珠光體的組織在實(shí)驗(yàn)中測量。從CCT曲線（圖6），可以看出的是，材料的AC3為811，AC1是736，臨界冷卻速率為15/ s，馬氏體起點(diǎn)是在350380之間，終點(diǎn)是在280300之間。實(shí)驗(yàn)對Gleeble-3800熱模的流變行為進(jìn)行模擬研究。樣品是在以15/ s的速度下加熱到950，在此溫度下保溫5分鐘得到均勻的奧氏體組織，然后以70/ s的冷卻速度迅速冷卻到試驗(yàn)溫度下，來完成等溫拉伸試驗(yàn)。在數(shù)據(jù)分析的過程中，用諾頓 - 霍夫定律來構(gòu)建模型： = 50.12 0.31&0.07 exp(2542 T ) 熱沖壓數(shù)值模擬是根據(jù)特性參數(shù)和材料模型來完成的，并將結(jié)果示于圖8。該材料在A區(qū)流動(dòng)速度最快和產(chǎn)生過大的變形，因此這里有20的最大減薄率和這將是最容易產(chǎn)生最大的集中應(yīng)力的地方。該物質(zhì)流動(dòng)時(shí)在B區(qū)被擠壓，其中導(dǎo)致出現(xiàn)最高溫度和厚度增加，因?yàn)檫@是最后接觸模具的地方。兩側(cè)的溫度最低，顯然這里的壓力最大且最先和模具接觸。該部分的最低溫度為600以上，根據(jù)模擬的結(jié)果，能滿足馬氏體相變的要求。在整個(gè)過程中模具的最高溫度低于200，那么成形部分的溫度低于150，制件在溫度為60以下淬火15秒的時(shí)間后，得到結(jié)構(gòu)良好的零件，而不起皺和開裂。淬火時(shí)間對于零件厚度的分布和馬氏體相變的形成是有幫助的，結(jié)果示于圖8。可以看出，在厚度為2mm左右（92.21），熱沖壓后，其厚度在淬火后更均勻（2毫米93.34）。3.2 熱沖壓工藝和優(yōu)化鋼板在高溫下的拉伸強(qiáng)度只有100MPa，如果有坯料夾持力（BHF的簡稱），由于零件的抗拉強(qiáng)度不能足以維持摩擦阻力該材料很快流入，零件被打破，這一現(xiàn)象可以從圖中9可以看出。沒有壓邊力時(shí)很少有部位在沖壓中起皺，因?yàn)樵诟邷貢r(shí)零件的強(qiáng)度低可以伸展自如。在實(shí)驗(yàn)中，溫度參數(shù)對微結(jié)構(gòu)的變化的影響是最大的，沖壓中對力學(xué)性能的成形參數(shù)也是有影響的。淬火時(shí)間和合理的散熱速度對馬氏體相變的影響是明顯的，沖壓力流入成型沖壓件。此外，坯料的熱傳遞時(shí)間是一個(gè)重要的因素，也就是說隨著熱傳遞時(shí)間的增加，初始變形溫度降低，需要較大的壓力完成沖壓。另外，馬氏體相變就不能完成。最佳工藝參數(shù)概括在表4中，在實(shí)踐中得到了質(zhì)量優(yōu)異的防撞梁，如圖10所示。3.3 力學(xué)性能測試和分析拉伸試驗(yàn)、硬度試驗(yàn)、厚度測試、殘余應(yīng)力測試和精度測試的結(jié)果如表5所示，從其中可以得到如下結(jié)論：抗拉強(qiáng)度達(dá)到1550MPa，是冷彎曲管狀梁的3.8倍（約400Mpa），最大減薄率17%滿足了沖壓厚度的要求，白光掃描顯示的在兩端焊接表面的尺寸精度完全滿足焊接件所要求的精度（0.5mm），如圖11所示，并且顯示為均勻的板條馬氏體微觀結(jié)構(gòu)。如圖12所示三點(diǎn)彎曲試驗(yàn)表明，冷沖壓管梁無法持續(xù)承受20mm以上變形量的力，而熱沖壓管梁的彈性好可以承受更大的力，其承受的力是冷沖壓管梁的2.5倍。根據(jù)GB20071-2006汽車側(cè)面碰撞標(biāo)準(zhǔn)，冷沖壓管梁與熱沖壓管梁的車輛側(cè)面碰撞圖像的對比如圖13所示。根據(jù)評估，按照C-NCAP規(guī)定，冷沖壓管梁車輛的得分是10.85分，熱沖壓管梁車輛的得分為16分（滿分）。超高強(qiáng)度鋼對車輛側(cè)面碰撞安全性能整體的提升起到了重要作用，并確保所有碰撞指標(biāo)均達(dá)到了國家標(biāo)準(zhǔn)。與冷沖壓管梁相比，厚度為2mm 的WTYPE熱沖壓梁的安全性能有顯著地增加，重量增加了38。為了滿足汽車車身輕量化的要求，兩種橫梁都在拉深深度和厚度這兩個(gè)方面進(jìn)行優(yōu)化設(shè)計(jì)的開發(fā)。當(dāng)熱沖壓鋼板的厚度從2mm減小到1.6毫米，冷彎管重量增加7.7;保持長度和寬度恒定，同時(shí)深度從32毫米減少到23.6毫米，重量下降9.32，帶動(dòng)所有能源減排。門梁的三點(diǎn)彎曲實(shí)驗(yàn)（圖14）表明，減速板厚或縮小深度，熱沖壓梁的彎曲性能降低同步以及板材厚度對于彎曲加工性起到重要作用，所以汽車零件可以實(shí)現(xiàn)從厚變薄的同時(shí)實(shí)現(xiàn)重量更輕巧塑身的目的。如圖14所示，輕量化的變形優(yōu)化門梁增加15毫米與將深門梁從32毫米減小到2mm相比，原來變形的6.7，變形增加量不會(huì)影響對汽車側(cè)面碰撞試驗(yàn)的結(jié)果，改進(jìn)輕巧的門梁滿足安全要求的兩倍并輕量級。結(jié)論1、 對冷卻管道冷卻效果影響最大的因素是冷卻管道到模具成形面管的距離，接著是管道間距和管道直徑。模具表面和冷卻管道的距離應(yīng)是管道間距和直徑合理設(shè)計(jì)的基礎(chǔ)。2、 熱沖壓模具開發(fā)、優(yōu)化的系統(tǒng)和工藝參數(shù)可以完全保證馬氏體和優(yōu)異的機(jī)械性能，具有平均拉伸強(qiáng)度1550Mpa的，6.5的伸長率，形狀精度0.5毫米;和優(yōu)化過程參數(shù)進(jìn)行加熱溫度為930，保溫4.5min的時(shí)間，形成了速度75毫米/秒，7Mpa的沖擊壓力，15s的熄滅時(shí)間，流程速度1.1米/秒的性能。3、 超高強(qiáng)度鋼板門梁進(jìn)行了優(yōu)化，實(shí)現(xiàn)碰撞測試的滿分，剛度增加了2.5倍，強(qiáng)度提高3.8倍，輕量化9.32，和原來的管道相比，取得安全和輕巧的雙目標(biāo)。致謝這項(xiàng)研究是由美國國家基礎(chǔ)研究發(fā)展計(jì)劃資助中國（2012CB724301），國際科技合作（2011DFA50810）的項(xiàng)目。參考文獻(xiàn)1. 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