外文翻譯-----沖壓成形與板材沖壓-預覽頁
【正文】 ect and indirect testing methods to assess the stamping property of the sheet metal. Practicality stamping test is the most direct method to assess stamping forming property of the sheet metal. This test is done exactly in the same condition as actual production by using the practical equipment and dies. Surely, this test result is most reliable. But this kind of assessing method is not prehensively applicable, and cannot be shared as a monly used standard between factories. The simulation test is a kind of assessing method that after simplifying and summing up actual stamping forming methods, as well as eliminating many trivial factors, the stamping properties of the sheet metal are assessed, based on simplified axialsymmetric forming method under the same deformation and stress states between the testing plate and the actual forming states. In order to guarantee the reliability and generality of simulation results, a lot of factors are regulated in detail, such as the shape and dimension of tools for test, blank dimension and testing conditions(stamping velocity, lubrication method and blank holding force, etc). Indirect testing method is also called basic testing method its characteristic is to connect analysis and research on fundamental property and principle of the sheet metal during plastic deformation, and with the plastic deformation parameters of the sheet metal in actual stamping forming, and then to establish the relationship between the indirect testing results(indirect testing value) and the actual stamping forming property (forming parameters). Because the shape and dimension of the specimen and the loading pattern of the indirect testing are different from the actual stamping forming, the deformation characteristics and stress states of the indirect test are different from those of the actual one. So, the results obtained form the indirect test are not the stamping forming parameters, but are the fundamental parameters that can be used to represent the stamping forming property of the sheet metal. 沖壓成形與板 材沖壓 1．概述 通過模具使板材產(chǎn)生塑性變形而獲得成品零件的一次成形工藝方法叫做沖壓。沖壓加工的原材料一般為板材或帶材，故也稱板材沖壓。 板材沖壓具有下列特點： （ 1）．高的材料利用率。 （ 5）．生產(chǎn)率高，操作簡單，容易實現(xiàn)機械化和自動化。如前所述，材料形狀有板材和帶材。沖壓成形具有如下幾個非常突出的特點。因此，以拉應(yīng)力作用為主的伸長類沖壓成形過程多于以壓應(yīng)力作用為主的壓縮類成形過程。 （ 4）．在沖壓成形時，模具對板材毛胚作用力所形成的約束作用較輕，不像體積成形（如模鍛）是靠與制件形狀完全相同的型腔對毛胚進行全面接觸而實現(xiàn)的強制成形。 由于沖壓成形具有上述一些在變形與力學方面的特 點，致使沖壓技術(shù)也形成了一些與體積成形不同的特點。借助于電子計算機與先進的測試手段，在對板材性能與沖壓變形參數(shù)進行實時測量與分析基礎(chǔ)上，實現(xiàn) 沖壓過程智能化控制的研究工作也在開展。 3．沖壓變形的分類 沖壓變形工藝可完成多種工序，其基本工序可分為分離工序和變形工序兩大類。 從本質(zhì)上看，沖壓成形就是毛胚的變形區(qū)在外力的作用下產(chǎn)生相應(yīng)的塑性變形，所以變形區(qū)內(nèi)的應(yīng)力狀態(tài)和變形特點景象的沖壓成形分類，可以把成形性質(zhì)相同的成形方法概括成同一個類型并進行體系化的研究?；谶@樣的分析，可以把各種形式?jīng)_壓成型中的毛陪變形區(qū)的受力狀態(tài)與變形特點，在平面應(yīng)力的應(yīng)力坐標系中與相應(yīng)的兩向應(yīng)變坐標系中以應(yīng)力與應(yīng)變坐標決定的位置來表示。 （ 2）判斷原材料沖壓性能的科學方法 ，確定可以確切反映材料沖壓性能的參數(shù)，建立沖壓性能的參數(shù)與實際沖壓成形間的關(guān)系，以及沖壓性能參數(shù)的測試方法等。雖然在沖壓生產(chǎn)中所用金屬板材的種類很多，但最多的原材料蛀牙是鋼板、不銹鋼板、鋁合金板及各種復合金屬板。另一方面，為了能夠依據(jù)沖壓件的形狀與尺寸特點及其所需的成形工藝等基本因素，正確、合理地選用板材，也必須對板材的沖壓性能有一個科學的認識與正確的判斷。但是 ，這種評定方法不具有普遍意義，不能作為行業(yè)之間的通用標準進行信息的交流。間接試驗法的特點是：在對板材在塑性變形過程 中所表現(xiàn)出的基本性質(zhì)與規(guī)律進行分析與研究的基礎(chǔ)上，進一步把它和具體的沖壓成形中板材的塑性變形參數(shù)聯(lián)系起來，建立間接試驗結(jié)果（間接試驗值）與具體的沖壓成形性能（工藝參數(shù)）之間的相關(guān)
畢業(yè)設(shè)計相關(guān)推薦
鄂ICP備17016276號-1