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任 務 書
院（系）： 專業(yè)：
班 級： 學生： 學號：
1、 畢業(yè)論文課題 直角多孔板沖壓連續(xù)模設計
2、 畢業(yè)論文工作自 20xx 年 3 月 12 日起至 20xx 年 6 月 15 日止
三、畢業(yè)設計進行地點 學院
四、畢業(yè)設計的內(nèi)容要求
(一) 設計之原始數(shù)據(jù)：
原始資料： “直角多孔板”實物一件
(二) 設計計算及說明部分內(nèi)容：
1.計算內(nèi)容與方案確定：
（1）成形零件設計：凹、凸模尺寸的計算和布置。
（2）壓力機的選擇
（3）結構系統(tǒng)設計計算：卸料力、推件力、頂件力的計算，排樣圖和工序件圖的設計計算，各工序沖裁力的計算，沖裁、拉深和壓制成形各工序間尺寸的計算，各工序沖裁力的計算 。
（4）強度設計和結構草圖設計：各部件的強度校核。
2. 設計內(nèi)容：
（1）落料、沖孔、拉深多工位級進模模具設計（用計算機完成繪制裝配圖）；
（2）各工序的凹、凸模機構、卸料機構、導料機構和排樣固定等機構的設計；
（3）編寫設計（論文）說明書（不少于2.0萬字，全部用計算機輸出）；
（4）綜述文獻（要求書寫6000～8000字與畢業(yè)設計內(nèi)容相關的綜述文章）
(三) 主要參考資料
1、薛啟翔《沖裁模具設計結構圖冊》，化學工業(yè)出版社。2005.3
2、郝濱?！稕_壓模具簡明設計手冊》，化學工業(yè)出版社 2004.11
3、《材料力學》，高等教育出版社。
4、高軍《沖壓模具標準件選用與設計指南》，化學工業(yè)出版社2007
5、林楓英 《沖壓模具設計基礎》，電子工業(yè)出版社 2005.11
6、《沖壓模具設計與制造過程仿真》, 化學工業(yè)出版社2007
(四)附屬專題
1、專題外文翻譯
檢索與閱讀和設計題目相關的外文資料，并書面翻譯4篇(3000～5000漢字)外文資料。
指導教師
接受畢業(yè)設計任務開始執(zhí)行日期 年 月 日
學生簽名
附件一 英文文獻翻譯
譯文：
板料沖壓成形工藝與模具設計制造中的若干前沿技術
摘要
板料成形技術是最重要的金屬成形方法之一,廣泛應用于工業(yè)領域。因此,成形制造技術及裝備水平已成為衡量一個國家制造水平的重要標志,在很大程度上決定產(chǎn)品的質(zhì)量、效益和開發(fā)能力,決定著一個國家制造業(yè)的國際競爭力。結合相關研究領域的發(fā)展趨勢和最新研究成果及其工業(yè)應用,針對目前板料成形技術發(fā)展現(xiàn)狀,提出板料沖壓成形工藝與模具技術的若干發(fā)展前沿問題。
2 板料沖壓工藝優(yōu)化設計技術中的若干前沿問題
板料成形過程是一個非常復雜的塑性成形過程，許多因素都直接或間接地影響到成形件的質(zhì)量。如果工藝參數(shù)、幾何參數(shù)以及材料等選擇不當，易產(chǎn)生起皺、破裂和回彈等缺陷。傳統(tǒng)的工藝分析和模具設計主要依靠設計者的經(jīng)驗，反復修改各種參數(shù)，并進行修模，耗時長，成本高，難以適應現(xiàn)代工業(yè)的要求。隨著計算機技術和數(shù)值計算方法的發(fā)展，數(shù)值模擬技術逐漸成為板料成形分析的一種重要手段。有限元模擬分析已廣泛應用于板料成形優(yōu)化設計中，然而，對有限元分析結果的判斷和相關參數(shù)的選擇依然依賴于經(jīng)驗。而最優(yōu)化技術的引入，使人們從試錯(Trial-error)的工作中解脫出來。在沖壓成形優(yōu)化領域，優(yōu)化方法可以分為三類：傳統(tǒng)優(yōu)化，啟發(fā)式優(yōu)化和近似模型優(yōu)化。由于板料沖壓成形過程是典型的強非線性問題，而傳統(tǒng)的優(yōu)化方法是基于梯度的，對于Hessian 矩陣為奇異的優(yōu)化問題，顯然難以處理沖壓成形優(yōu)化問題；啟發(fā)式算法包括遺傳算法、粒子群、擬退火等算法，這類算法可以找到優(yōu)化問題的全局優(yōu)化點，可以保證優(yōu)化的精度和效果。但是，優(yōu)化求解中需要反復修正CAE模型并調(diào)用相應的有限元程序，這需要耗費大量的計算資源。隨著設計參數(shù)數(shù)量和復雜度的增加，不僅計算成本會成倍增加，而且計算時間會大幅度增加。基于近似模型的優(yōu)化方法是求解大型問題最有希望的方法之一，鑒于其高效性，廣泛應用于工程優(yōu)化領域，如果能夠高效建立可靠的近似模型，很多大規(guī)模的工程問題可以迎刃而解。近年來，隨著研究的深入，該技術也大量應用于沖壓成形問題的優(yōu)化，成為目前沖壓優(yōu)化領域的研究熱點。
2.1 試驗設計方法
通過試驗發(fā)現(xiàn)，樣本點的布置對具體的工程問題以及相應近似模型的構建具有較強的敏感性，在有限的樣本點范圍內(nèi)，采用不同方法生成的樣本點會導致優(yōu)化結果的差異。針對這些問題，國內(nèi)外很多學者提出了縮減空間的概念?？臻g縮減技術分為兩類，一類是建立在敏感性分析基礎上的設計變量篩選方法[23]。BROWNE 等[24]通過分析凸凹模幾何形狀、壓邊力、凸模壓力、摩擦和拉伸速度等對板厚為0.19 mm 的筒形件成形的影響，采用試驗設計的方法進行了大量的試驗，結果表明：除了壓邊力和拉深速度對最終成形性能影響不大之外，其他參數(shù)對成形性能均有較大影響。NAKAMURA 等[25]采用敏感性分析的方法將影響目標函數(shù)的7 個參數(shù)減少到2 個，有利于優(yōu)化的進行。另一類是基于設計空間的縮減方法。前者主要是通過敏感性分析，篩選出與目標函數(shù)相關性大的參數(shù)作為設計變量。后者則是建立在工程經(jīng)驗和空間分類技術之上，通過對設計變量的分析，將設計變量控制在合理的范圍內(nèi)，并建立更為精確的近似模型。目前已經(jīng)發(fā)展的技術包括：基于分層技術的小設計空間方法[26-27]，移動控制布點技術[28]、基于信任域的布點方法[29]、自適應試驗設計方法[30]、多層次搜尋方法[31-32]等。同傳統(tǒng)的試驗設計方法相比，這類方法將設計空間控制在比較小的范圍內(nèi)，在減少樣本點數(shù)目的同時，避免了全局擬合，使近似模型的精度大為提高。這些方法通常建立在某些假設之上，如凸集合連續(xù)性要求等等。對于實際工程問題的優(yōu)化，“在線”布點技術依然存在以下瓶頸。首先，初始設計參數(shù)區(qū)間的確定是以工程經(jīng)驗為依據(jù)的。對于缺乏先驗性的工程問題，當設計空間過小時，可能丟失最優(yōu)解；反之，近似模型難以構造，精度也得不到保證。其次，對于復雜的非線性問題，隨著設計參數(shù)的增加，迭代次數(shù)和樣本的數(shù)目都會大幅度增加。而每次試驗的開銷達到一定量級時，算法的可行性難以保證。近似模型的精度是影響優(yōu)化結果的最直接因素,在優(yōu)化領域，國內(nèi)外采用的近似模型構造技術種類繁多，常用的包括基于多項式的擬合技術，Kriging插值，徑向基函數(shù)(Radial basis function，RBF)插值，自適應響應面技術等。近年來，近似模型構造技術發(fā)展很快，各種逼近和擬合算法層出不窮。但實質(zhì)上，這些方法并沒有取得突破性進展。總體來說，大多數(shù)近似模型構造方法的性能均是建立在回歸分析、方差分析以及無偏估計等以統(tǒng)計學理論為依據(jù)的基礎之上，判斷這類近似模型優(yōu)劣的標準可以歸結為所謂經(jīng)驗風險最小化準則，但經(jīng)驗風險最小并不一定意味著期望風險最小。簡而言之，這類技術試圖用十分復雜的模型去擬合有限的樣本。因此，導致喪失了推廣能力，難以反映研究目標的實質(zhì)和特性。因此，泛化性能出色的基于概率的支持矢量機回歸近似模型構造技術提供了一種能夠應用于沖壓成形優(yōu)化的選擇。同其他主流方法相比，支持向量機回歸技術的缺陷在于其計算效率，因此需要建立更為高效的試驗設計方法。
2.2 并行優(yōu)化技術
同串行算法相比，并行算法具有以下優(yōu)勢。由于采用并行構架，計算效率大幅度提高，可以擴大樣本數(shù)量，從而導致近似模型精度提高；每個迭代步中的樣本信息遠遠大于串行算法，因此更容易收斂。JAKUMEIT 等[33]建立了并行Kriging 迭代算法，在優(yōu)化板金成形參數(shù)時的結果表明，它確實能更快、更穩(wěn)地收斂優(yōu)化過程；WANG 等[34]建立了基于并行智能布點算法的Kriging 近似模型體系和支持矢量機回歸優(yōu)化體系，并成功應用于拉延筋的優(yōu)化設計。隨著計算機技術的發(fā)展，基于圖形處理器的通36 機 械 工 程 學 報 第46卷第10期期用計算技術(General purpose graphic process unit，GPGPU)發(fā)展很快，它不僅能夠進行圖形處理，而且能完成CPU 的運算工作，更適合高性能計算，并能使用更高級別的編程語言，在性能和通用性上更加強大。從狹義的GPGPU 應用來說，GPGPU 就是功能強化的GPU，彌補了CPU 浮點運算能力的嚴重不足。目前湖南大學汽車車身先進設計制造國家重點實驗室已將該技術成功應用于并行有限元仿真中，已取得初步成效，并已著手建立基于GPGPU技術的板料成形工藝與模具優(yōu)化設計體系。
3 基于CAE 技術的沖壓工藝與模具
制造的若干前沿問題板料沖壓成形工藝發(fā)展歷史悠久，隨著信息技術和其他相關技術的發(fā)展和應用，基于CAE 的沖壓分析越來越多地應用于板料成形工藝的設計中，不僅為工藝設計提供了更加精確的設計方法，同時也為工藝的創(chuàng)新提供了新的途徑，如通過CAE 技術的計算和模擬，在沖壓分析中可以實現(xiàn)基于原理變革的工藝創(chuàng)新和基于計算方法變革的工藝創(chuàng)新。
3.1 拉延筋技術
在現(xiàn)有沖壓工藝技術中，拉延模具通常由凹模、凸模、壓邊圈三部分組成。壓邊圈的壓料面上通常設置拉延筋以控制板料在沖壓中所受的流動阻力，防止工件出現(xiàn)起皺或拉裂等成形缺陷。原有拉延模具的拉延筋的設置一般為垂直材料自然流動方向的直線或環(huán)線。由于拉延筋處的板料變形通常比其他部位的變形更為復雜，傳統(tǒng)的設計計算方法難以定量計算給定形狀和尺寸的拉延筋能提供的流動阻力，這就使得傳統(tǒng)的拉延筋布置和參數(shù)設計主要憑經(jīng)驗和直覺進行，再通過反復的打磨和調(diào)試來獲得符合要求的拉延筋形狀和尺寸。這個過程通常是導致傳統(tǒng)模具調(diào)試時間較長的重要原因。同時對于深拉延件，傳統(tǒng)拉延筋布置和設計用來克服角部起皺或拉裂效果不佳，成形缺陷經(jīng)常出現(xiàn)。為解決上述工藝方案中常出現(xiàn)的成形缺陷，湖南大學汽車車身先進設計制造國家重點實驗室應用CAE 技術，對拉延筋機理進行了深入的研究，發(fā)明了斜拉延筋工藝。新的斜拉延筋技術除在壓邊圈的壓料面上設置有傳統(tǒng)的拉延筋外，還在壓邊圈的壓料面的角部創(chuàng)新性地設置有斜拉延筋。傳統(tǒng)拉延筋主要提供板材在沖壓中的具有被動性質(zhì)的流動阻力，而斜拉延筋則除提供流動阻力外，還可提供具有主動性質(zhì)的引導材料流動的作用力。這就使得斜拉延筋對材料流動具有很好的控制作用，在拉延件沖壓特別是深拉延件沖壓中能有效克服拉延件的起皺或拉裂缺陷。斜拉延筋工藝對設計提出了更高的要求。因為斜拉延筋能提供具有主動性質(zhì)的引導材料流動的作用力，其形狀、位置和尺寸參數(shù)必須足夠精確，否則可能導致相反的效果。由于斜拉延筋的作用機理不同于傳統(tǒng)拉延筋，現(xiàn)有可借鑒的設計理論和經(jīng)驗很少，因此必須發(fā)展能準確模擬真實拉延筋的計算機仿真技術。
3.2 熱成形技術
先進高強度鋼板由于具有強度高、較好的應變硬化能力、較強的均勻變形能力、更高的疲勞特性而得到廣泛應用，特別是在汽車工業(yè)，由于這些優(yōu)越的力學性能而具有更多的降低板厚的可能，通過減少鋼板的厚度，在保證其他性能相當?shù)臈l件下可達到減輕汽車重量的目的。 因此，先進高強度鋼目前已成為較理想的汽車輕量化材料之一。國際上已研制出超輕鋼車身，在滿足2004 年美國碰撞法規(guī)前提下，應用先進高強度可在不增加成本的條件下使車身質(zhì)量減少20%。因此，先進高強度鋼在汽車減重、節(jié)能、提高安全性、降低排放等方面展現(xiàn)了廣闊前景。在高強度鋼板的應用中，由于強度的大幅度提高，給成形工藝和模具設計制造帶來了許多新的困難，如強度增大和厚度減薄導致沖壓成形中的回彈增加，強度和硬度提高導致成形力增大和模具容易磨損等。和普通鋼板相比，高強度鋼板在沖壓過程中不僅會造成較大的彎曲回彈和扭曲回彈，而且還會產(chǎn)生嚴重的側壁卷曲，這將嚴重影響沖壓件的形狀尺寸精度和整車裝配。超高強度鋼的回彈問題對當今沖壓工藝提出了新的挑戰(zhàn)，成為汽車制造行業(yè)和學術界研究的一大熱點。熱沖壓成形技術是解決高強度鋼板難成形問題和減少回彈的有效途徑。熱沖壓是將沖壓板材在奧氏體溫度區(qū)加熱，在高溫下沖壓成形并使其在模具內(nèi)進行馬氏體相變后，在保證高強度的前提下獲得需要的形狀。目前，高強度鋼板采用熱沖壓技術具有以下特點：成形性能得到優(yōu)化，回彈極小，產(chǎn)品尺寸精度高，成形負荷小，不必對沖壓機進行升級；熱成形過程工件可以獲得高延展率，并可以大幅度增加零件的強度。目前的研究關鍵是要建立快速加熱和冷卻過程中的高強度鋼板本構關系變化規(guī)律及對材料強度影響規(guī)律，發(fā)展能準確模擬熱成形過程的計算機仿真技術，通過數(shù)值仿真與模擬，探明高強度鋼板在受熱和受力雙重作用下材料性能的變化規(guī)律和塑性成形機理以及冷卻速度對成形性能的影響機理，從而確定熱成形工藝參數(shù)的變化對成形件質(zhì)量的影響特性。
原文：Some New Topics on Process Design and Mould Manufacture for Sheet Metal Forming
LI Guangyao WANG Hu YANG Xujing ZHENG Gang
（State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body; Hunan University; Changsha 410082）;
機械工程學報, Journal of Mechanical Engineering, 編輯部郵箱 2010年 10期??
summary
Sheet metal forming technique is one of the most important forming methods and is widely applied in industrial fields.Therefore,forming manufacturing techniques represent a country s manufacturing level.Furthermore,the quality,profit and development capability of the product also depend on forming techniques.Some new topics on process design and mould manufacture for sheet metal forming are proposed according to the recent development and applications in this field.
The 2sheet metal stamping process design optimization technique of cutting edge issues in
Sheet metal forming process is a very complex plastic forming process, many factors which directly or indirectly affects forming quality. If the process parameters, geometry parameters and the material choice is undeserved, easy wrinkling, cracking and springback defect. The traditional process analysis and die design for the mainly rely on the experience of the designer, repeated modification of various parameters, and to repair mould, time-consuming, high cost, difficult to adapt to the requirements of modern industry. With the development of computer technology and numerical calculation method, numerical simulation technology of sheet metal forming analysis has gradually become an important means of. Finite element simulation analysis has been widely used in sheet metal forming process of optimal design, however, the result of finite element analysis judgment and selection of relevant parameters is still dependent on experience. Optimization of technology introduction, make people from trial and error ( Trial-error ) work out. In forming optimization, optimization methods can be divided into three categories: traditional optimization, heuristic optimization and approximation model optimization. Due to the sheet metal forming process is a typical nonlinear problem, and the traditional optimization method is based on the gradient, for Hessian matrix is singular optimization problem, it is obviously difficult to processing stamping optimization problem; heuristic algorithm including genetic algorithms, particle swarm, quasi annealing algorithm, this algorithm can find the global optimization problem point, can guarantee the precision and performance optimization. However, optimization requires repeated modified CAE model and calls the corresponding program of the finite element method, which requires a lot of computing resources. With the design parameters of quantity and the complexity increases, not only calculate the cost will be multiplied, and the computing time will increase substantially. Based on the approximation model for optimization method for solving large problems is the most promising method, in view of its high efficiency, widely used in the field of engineering optimization, if can efficiently establish reliable approximation model, many large-scale engineering problems can be smoothly done or easily solved. In recent years, with the deepening of the research, the technology is also applied to a large number of stamping forming of the optimization problem, become the research hotspot in the field of stamping optimization.
2.1methods of experimental design
Through the experiment, the sample points layout of the specific engineering problem and the corresponding approximate model has strong sensitivity, the sample points in a limited range, using different methods to generate samples can lead to optimal result differences. In view of these problems, many domestic and foreign scholars put forward the concept of reduced space. Space reduction technology is divided into two categories, one category is established on the basis of sensitivity analysis of design variables screening method [23]. BROWNE [24] through analysis of punch and die geometry, BHF, convex die pressure, friction and stretching speed on the plate thickness of 0.19mm cylinder forming effect, using the experimental design method for a large number of trials, the results show that: in addition to the blank-holder force and drawing speed on the final forming performance little, other parameters on forming properties of. NAKAMURA [25] by using sensitivity analysis method will affect the target function with 7parameters are reduced to 2, is conducive to optimizing the. The other is based on the design of space reduction method. The former mainly through sensitivity analysis, screening out of objective function and correlation with large parameters as design variables. The latter is based on the engineering experience and spatial classification techniques, through the design variables in the analysis, the design variables are controlled in a reasonable range, and build a more accurate approximation model. Has been the development of the technology include: Based on hierarchical technology small space design method [26-27], mobile control layout technique [28], trust domain based layout method [29], the adaptive test design method [30], multi-level search method [31-32]. With the traditional test method compared to, this kind of method to design space control in a relatively small range, the reduced sample number at the same time, to avoid the global fitting, so that the approximation accuracy is greatly improved. These methods are usually based on some assumptions, such as convex set continuity requirements etc.. For the practical engineering optimization problems," online" layout technique is below the bottleneck. First of all, the initial design parameters interval to determine the engineering experience as the basis. For lack of a priori knowledge of engineering problems, when the design space of hours, may lose the optimal approximation model; instead, it is difficult to build, the precision can not be guaranteed. Secondly, for the complex nonlinear problems, with the design parameter increases, the number of iterations and the number of samples will increase. Each time the test spending reaches a certain level, it is difficult to guarantee the feasibility of the algorithm. Approximation accuracy is influenced by the optimization results of the most direct factor, in the field of optimization at home and abroad, the approximate model construction technology of variety, commonly used include based on polynomial fitting technique, Kriging interpolation, radial basis function ( Radial basis function, RBF ) interpolation, adaptive response surface technique. In recent years, approximate model technology develops very fast, and various approximation algorithm fitting emerge in an endless stream. But in fact, these methods have not achieved breakthrough progress. In general, most approximate model construction method performance are based on regression analysis, analysis of variance and unbiased estimation based on the statistics theory based on this kind of approximate model, judging criterions can be attributed to the so-called empirical risk minimization rule, but empirical risk minimization does not necessarily mean that the expected risk minimum. In short, this kind of technology is tried to use very complex model to fitting Limited sample. Therefore, lead to a loss of generalization ability, cannot reflect the research target of the essence and character. Therefore, the generalization performance of the excellent probability based on support vector machine regression approximation model technology provides a can be applied to the optimal selection of stamping forming. Compared with other mainstream method, support vector machine SVM regression technique flaw lies in its computational efficiency, so it is necessary to build more efficient methods of experimental design.
2.2parallel optimization technique
Compared with the serial algorithm, parallel algorithm has the following advantages. Due to the adoption of parallel framework, computational efficiency is greatly improved, can expand the number of samples, thus leading to improve the accuracy of approximate model; each iteration of the sample information is far greater than the serial algorithm, thus more easily convergent. JAKUMEIT [33] to establish a parallel Kriging algorithm in the optimization of sheet metal forming parameters, the results show that, it can be faster, more stable convergence of the optimization process; WANG [34] was established based on the parallel intelligent layout algorithm of approximate Kriging model system and support vector machine regression optimization system, and successfully applied to the drawbead optimization design. With the development of computer technology, based on the graphics processor through36machine machinery engineering process study reported forty-sixth volume tenth period calculation technique ( General purpose graphic process unit, GPGPU ) is developing very fast, it can not only for graphics processing, and can complete the CPU operation work, is more suitable for high performance computing, and can use more high level programming language, in performance and versatility of a more powerful. From the narrow GPGPU application, GPGPU is strengthening the function of GPU, for the CPU floating point arithmetic ability shortage. Advanced design and manufacturing for vehicle at Hunan University State Key Laboratory of the technology has been successfully applied in parallel in the finite element simulation, has achieved initial results, and has started to build the GPGPU technology based on sheet metal forming process and die design system.
3 based on the CAE technology of the stamping process and die
Manufacture of some frontier problems in sheet metal forming process has a long history of development, with the development of information technology and other related technology development and application, based on the CAE analysis is more and more used in stamping of sheet metal forming process design, not only for the process design provides more precise design method, but also for the technological innovation provides new ways, such as through the use of CAE technology calculation and simulation, stamping in the analysis can be achieved based on the principle of change of process innovation and based on the calculation method of transformation process innovation.
3.1bead technique
In the existing stamping technology of drawing die, usually by concave die, punch, a pressing edge ring is composed of three parts. Blank holder pressure surface usually setting drawbead to control sheet in stamping the flow resistance, prevents the workpiece wrinkling or cracking forming defects. The original drawing mould drawbead setting is generally perpendicular to the flow direction of the straight line or natural materials link. As a result of drawbead of sheet deformation usually than in other parts of the deformation is more complex, the traditional design and calculation methods are difficult to quantify the given shape and size of the drawbead can provide resistance to flow, which makes the traditional drawbead layout and parameter design mainly by experience and intuition, and through repeated grinding and debugging to meet the requirements of the drawing rib shape and size. This process is usually lead to the traditional mold debugging time longer important reason. At the same time for deep drawing, traditional drawbead layout and design to overcome the corner wrinkling or cracking effect, forming defect often appears. In order to solve the above technical scheme often appears in the forming defects of automobile body, Hunan University State Key Laboratory of advanced design and manufacture technology for application of CAE, drawbead mechanism of in-depth research, the invention of oblique drawbead. New slant on drawbead technology except in the pressing ring is arranged on the surface of the binder traditional drawbead, still pressing edge ring binder corner innovatively with inclined drawbead. Traditional drawbead mainly provide sheet in stamping with the passive properties of the resistance to flow, and the oblique drawbead except to provide resistance to flow, can also provide the active nature of the guide material flow force. This makes the oblique Drawbead on material flow and has good control effect, in the drawing stamping especially deep drawing stamping can effectively overcome the drawing wrinkling or crack. Oblique drawbead design put forward higher requirements. Because of an oblique drawbead can provide active nature of the guide material flow force, its shape, position and size parameters must be sufficiently accurate, otherwise may cause the opposite effect. Because of the oblique drawbead mechanism is different from the traditional drawbead, existing reference design theory and experience little, therefore must develop accurate simulation of real drawbead computer simulation technology.
3.2 hot forming technology
Advanced high strength steel plate with high strength, good strain hardening ability, strong uniform deformation capacity, higher fatigue properties and widely used, especially in the automotive industry, due to the excellent mechanical performance and more reduce plate thickness may, by reducing the thickness of the sheet, the other performance conditions can reach the purpose of reducing vehicle weight. Therefore, advanced high strength steel has become the ideal lightweight automobile materials. Ultra light steel auto body international has developed in the United States, meet the 2004crash regulations premise, the application of advanced high strength without increasing the cost of conditions to reduce the 20% body quality. Therefore, advanced high strength steel in vehicle weight, energy conservation, improve safety, reduce emissions and so on shows broad prospects. In high strength steel application, due to the intensity of the increase, to forming process and mold design and manufacturing has brought many new difficulties, such as strength increases and the thickness of lead in stamping forming springback increase, strength and hardness increase in forming force and easy mould wear. And ordinary steel, high strength steel sheet in stamping process can not only cause the larger bending and torsion springback, but also will produce the serious side wall curl, which will seriously affect the shape of the stamping parts size precision and the whole assembly. Ultra high strength steel rebound problem of the stamping process and put forward the new challenge, as the automobile manufacturing industry and academic research area. Hot stamping technology is to solve the difficult problem of high strength steel sheet forming and efficient way reduced bounce. Hot stamping is a sheet metal stamping in the austenitic temperature zone heating in high temperature, stamping and make it in the mold of martensitic transformation, in ensure the premise of high strength required shape. At present, the high strength steel plate by hot stamping technology has the following characteristics: the forming performance is optimized, rebound small, product size and high precision, the forming load is small, do not need to stamping machine upgrade; hot forming process of the workpiece can be obtained with high elongation, and can greatly increase the strength of the parts. The current study is the key to the establishment of rapid heating and cooling process of high strength steel constitutive relation change rule a