外文翻譯--基于Dynaform沖壓工藝的影響因素分析[中文2604字]【中英文文獻(xiàn)譯文】
外文翻譯--基于Dynaform沖壓工藝的影響因素分析[中文2604字]【中英文文獻(xiàn)譯文】,中文2604字,中英文文獻(xiàn)譯文,外文,翻譯,基于,dyna,沖壓,工藝,影響,因素,分析,中文,中英文,文獻(xiàn),譯文
山東建筑大學(xué)畢業(yè)設(shè)計(jì)
外文文獻(xiàn)及譯文
文獻(xiàn)、資料題目:The Impact Analysis of Stamping
Process Factors Based on Dynaform
文獻(xiàn)、資料來(lái)源:Advanced Materials Research
外文文獻(xiàn): The Impact Analysis of Stamping Process Factors Based on Dynaform
Abstract
Combining with practical needs in production, it carried out the numerical simulation analysis of automobile beam stamping forming process based on Dynaform in this paper. According to quality evaluation index of forming parts, it analyzed the effect of variation of blank holder force,the stamping speed, the coefficient of friction and draw bead on stamping quality. It forecast the quality problems happened in forming process, which provides the theoretical basis for design of stamping process and mold.
Keywords: stamping forming, numerical simulation, process factors, impact analysis, Dynaform
Introduction
Due to high production efficiency, low processing costs and stability of product dimensional accuracy, sheet metal stamping is widely used in the field of automobile manufacturing [1-3].Combining with practical needs in production, it carried out the numerical simulation analysis of automobile beam stamping forming process based on Dynaform in this paper, and analyzed the effect of manufacturing process factors on stamping quality, and achieved the aim of optimizing stamping process parameters and reducing mold trial number.
Establishment of finite element model
According to technical requirements of automobile beam putted forward by automobile manufacturer and stamping processes, the three-dimensional model was bulit with craft supplement which meets the numerical simulation requirements using UG. With importing the three-dimensional model into Dynaform, the model was mesh by quadrilateral using the adaptive grid technology. Then check and repair the finite element model. The finite element model of punch and die was established by using the copy command. The stamping direction was adjusted according to the actual circumstances [4-5]. The blank sheet, blank holder, the die clearance and the positioning was completed. The finite element model of stamping numerical simulation is showed as Fig. 1
Effect analysis of process factors on stamping
Influence of Blank Holder Force on forming. BHF in the sheet metal stamping process can generally be estimated with the following formula:
FBHF=Aq (1)
In equation (1), FBHF is blank holder force (N); A is the contact area of blank holder and blank (mm2);q is the blank holder force per unit area (MPa);In Dynaform, the Static friction coefficient is 0.125, the punching speed is 5000mm/s, the clearance between punch and die is 1.1t (t is the thickness of sheet),and the down mold is fixed without moving[6-7]. It carried out numerical simulation analysis respectively when BHF are taken as four series: 490kN, 540kN, 590kN, 630kN. The Forming limit diagram in numerical simulation is showed in Fig. 2 while the blank holder force is 590kN.
It can be seen from Fig. 2, the part does not cracked after stamping, but wrinkling phenomenon is occurred in edge. It is indicated that the material flow is not sufficient in this position which causes partial thickening, that’s why the process improvement is needed. The maximum and minimum thicknesses of the part are presented in the waste zone, which has no effect on the part quality finally. It focus on the effective area of part after stamping, the maximum thinning rate, maximum thickening rate and other date in effective are under four different BHF are managed in Table 1
It can be seen from Table 1, the maximum thinning rate is gradually increasing and the maximum thickening rate shows a decreasing trend while the BHF is increasing. These two parameters are the evaluation index of sheet quality after forming, but they cannot indicate the equality degree of sheet thickness after forming. Therefore, the uniformity degree of sheet thickness after forming is characterized by the average thickness and deviation in this paper. The average thickness is the mean value of all the nodes’ thickness in the numerical simulation. The average deviation refers to the mean value of absolute deviation between each nodes and the average thickness, and the mathematical expression of the average deviation is , which is used to reflect the dispersion degree of each node thickness, i.e. the uniformity degree of sheet thickness.
It can be seen from Fig. 3, as the blank holder force increasing, the average thickness of part is gradually reducing, while the average deviation is increasing step by step. It is indicated in these part that the dispersion degree of each nodes thickness is increasing along with BHF increasing, and the uniformity of this part after forming becomes worse. Thus, under the circumstance of meeting the requirement of thinning and thickening, we can choose the process program with smaller BHF in order to improve the uniformity of part after forming in the actual production.
Influence of stamping speed on forming. Four programs of numerical simulation analysis in which stamping speed is respectively 4000mm/s, 4500mm/s, 5000mm/s, 5500mm/s were conducted to research the impact of stamping speed on part forming, when the BHF is 590kN. Some analysis data with four programs of numerical simulation are collated in Table 2.
As it can be seen from Table 2, with stamping speed increasing, the maximum thinning rate shows an increasing trend and there is a peak of maximum thickening in this interval. With stamping speed increasing, the average thickness of part gradually becomes thicker after stamping. In the interval of low stamping speed, the value of average deviation is large and when the stamping speed is large, the value is decreased. That illustrates in the condition of high stamping speed, the uniformity of part after stamping could be better. Therefore in the actual production under the circumstance of meeting the requirement of thinning and thickening, we can choose the process program with higher stamping speed in order to improve the uniformity of part after forming according to the actual situation of stamping equipment.
Influence of friction coefficient on forming. Four programs of numerical simulation analysis in which coefficient of friction is respectively 0.1, 0.125, 0.15, 0.175 were carried out in this paper when the stamping speed is 5000mm/s and the BHF is 590kN. The maximum thinning rate, maximum thickening rate and other date in the effective area are managed in Table 3.
It can be seen from Table 3, as coefficient of friction increasing, the maximum thinning rate shows a decreasing trend, while the maximum thickening rate has a valley values in this interval with little value change. Along with friction coefficient increasing, the average thickness of part decreases gradually and the average deviation increases step by step, and the uniformity of part after forming become worse. Therefore in the actual production under the circumstance of meeting the requirement of thinning and thickening, we can choose the process program with smaller coefficient of friction in order to improve the uniformity of the part after forming.
Influence of draw bead on forming. For this part, the two draw beads are respectively arranged on the upper and lower side of the die. The layout of draw bead is shown in Fig. 4. In Dynaform, the contact type select FPRMING_ONE_WAY_S_S. BHF is 590kN, Static friction coefficient is 0.125, the stamping speed is 5000mm/s, the clearance between punch and die is 1.1t, the down mold is fixed without moving. Under the above condition the forming limit diagram with draw bead and without draw bead are shown in Fig. 4.
It can be obviously seen from Fig. 5 that the security area (shown in green) of the program with draw bead is more than it of program without draw bead while other parameters are the same. It indicates that the program with draw bead has the better condition of material utilization and the wrinkling in effective region has been relieved. Therefore, it can improve the utilization of the material during forming with draw bead.
After analysis and comparison of process parameters with different values, combined with actual situation, the final process parameters is as following: the BHF is 590kN, the stamping speed is 5000mm/s and the coefficient of static friction is 0.125, it selects the draw bead layout shown in Fig.4, finally the forming limit diagram of numerical simulation is shown in Fig. 5(left). The consistency is good compared with the actual production situation.
Conclusions
(1) The thinning rate, thickening rate, stress and the strain distribution after stamping are the important indicators which characterize the forming quality. In the effective area, the maximum value of these indicators should be focused on. The uniformity degree of sheet after stamping can be characterized by the average thickness and the average deviation through data processing.
(2) Taking an automobile’s beam forming as an example, the impact of BHF, stamping speed, coefficient of friction and draw bead on forming quality of stamping was researched and the changing trend of the impact was analyzed in this paper. Finally the process parameters were determined combined with actual production situation. The result of numerical simulation has a great agreement with actual situation of production.
(3) The impact of multi-factors on the stamping quality can be studied with analysis of stamping simulation. It can take place the repeated tryout in actual production to achieve the prediction and scientificity of stamping process plan, enhance the accurate and reliability of mold design and decrease the cycle of mold manufacturing and debugging, which has certain significance for the actual production.
References
[1] Huang Yao, Zhu Qing, Wang Leigang, “Simulation on Multi-steps Stamping for Shock Absorber Lid Based on DYNAFORM” , Journal of Hot Working Technology, vol.40,no.15, pp.73-75, 2011.
[2] Heber Castro Silva ,Sérgio Fernando Lajarin ,Paulo Victor P, “Marcondes Analysis of Numerically Simulated True Strain on High Stampability Sheets” , Journal of January-March ,vol. 32, no. 1,pp.21-27, 2010.
[3] Dae-Cheol Ko,Seung-Hoon Cha, Sang-Kon Lee, Chan-Joo Lee, Byung-Min Kim,“Application of a feasible formability diagram for the effective design in stamping processes of automotive panels”, Journal of Materials and Design ,vol.31, pp.1262–1275, 2010.
[4] Wan Min, Li Dongsheng, Qiao Lihong, The computer analysis technology of sheet metal forming, BeiHang University Press, China,2008.
[5] Bao Xiangjun , Jiang Hongfan , He Dannong , Li Congxin, “Numerical Simulation of the Influence of Material Parameters on Autobody Panel Stamping Formability”, Journal of Materials for Mechanical Engineering,vol.25,no.7,pp. 15-17, 2001.
[6] Xie Hui, “Analysis of critical stress and prediction of sheet's wrinkling in sheet metal forming”, Journal of Computational Mechanics, vol.20,no.1,pp.96-100, 2003.
[7] Bor-Tsuen Lin , Chun-Chih Kuo,Int J Adv ,“Application of an integrated CAD/CAE/CAM system for stamping dies for automobiles”,Journal of Manuf Technol ,vol.35,pp.1000–1013, 2008.
13
中文翻譯: 基于Dynaform沖壓工藝的影響因素分析
摘要
結(jié)合生產(chǎn)實(shí)際需要,在本文中,基于DYNAFORM進(jìn)行了汽車大梁沖壓成形過(guò)程數(shù)值模擬分析。根據(jù)零件的成形質(zhì)量評(píng)價(jià)指標(biāo),分析了壓邊力變化的影響,沖壓速度,摩擦和拉延筋的沖壓質(zhì)量系數(shù)。它預(yù)測(cè)成形過(guò)程中發(fā)生的質(zhì)量問(wèn)題,為沖壓工藝及模具設(shè)計(jì)提供了理論依據(jù)。
關(guān)鍵詞:沖壓成形,數(shù)值模擬,工藝因素,影響分析,模擬
引言
Due to high production efficiency, low processing costs and stability of product dimensional accuracy, sheet metal stamping is widely used in the field of automobile manufacturing [1-3].Combining with practical needs in production, it carried out the numerical simulation analysis of automobile beam stamping forming process based on Dynaform in this paper, and analyzed the effect of manufacturing process factors on stamping quality, and achieved the aim of optimizing stamping process parameters and reducing mold trial number.
由于生產(chǎn)效率高,加工成本低、產(chǎn)品尺寸精度穩(wěn)定,沖壓件廣泛應(yīng)用于汽車制造領(lǐng)域。結(jié)合生產(chǎn)實(shí)際需要,在本文中基于DYNAFORM進(jìn)行了汽車大梁沖壓成形過(guò)程的數(shù)值模擬分析,并分析了制造工藝因素對(duì)沖壓件質(zhì)量的影響,并實(shí)現(xiàn)了優(yōu)化工藝參數(shù),減少試模次數(shù)的目的。
有限元模型的建立
According to technical requirements of automobile beam putted forward by automobile manufacturer and stamping processes, the three-dimensional model was bulit with craft supplement which meets the numerical simulation requirements using UG. With importing the three-dimensional model into Dynaform, the model was mesh by quadrilateral using the adaptive grid technology. Then check and repair the finite element model. The finite element model of punch and die was established by using the copy command. The stamping direction was adjusted according to the actual circumstances [4-5]. The blank sheet, blank holder, the die clearance and the positioning was completed. The finite element model of stamping numerical simulation is showed as Fig. 1
根據(jù)汽車制造商提出的汽車梁技術(shù)要求和沖壓過(guò)程的三維模型,建立了工藝補(bǔ)充符合要求,利用UG的數(shù)值模擬。導(dǎo)入到Dynaform的三維模型,模型是由四邊形網(wǎng)格利用網(wǎng)格自適應(yīng)技術(shù),然后檢查和修復(fù)的有限元模型,通過(guò)使用復(fù)制命令建立了沖床和模具的有限元模型。沖壓方向是根據(jù)實(shí)際情況調(diào)整,板料、壓邊圈、模具間隙和定位確定完成后,沖壓成形數(shù)值模擬的有限元模型如圖1。
工藝因素對(duì)沖壓效果分析
Influence of Blank Holder Force on forming. BHF in the sheet metal stamping process can generally be estimated with the following formula:
壓邊力對(duì)成形的影響。壓邊力沖壓過(guò)程一般可以用以下公式估算:
FBHF=Aq (1)
FBHF = Aq (1)
In equation (1), FBHF is blank holder force (N); A is the contact area of blank holder and blank (mm2);q is the blank holder force per unit area (MPa);In Dynaform, the contact type is FPRMING_ONE_WAY_S_S, the Static friction coefficient is 0.125, the punching speed is 5000mm/s, the clearance between punch and die is 1.1t (t is the thickness of sheet),and the down mold is fixed without moving[6-7]. It carried out numerical simulation analysis respectively when BHF are taken as four series: 490kN, 540kN, 590kN, 630kN. The Forming limit diagram in numerical simulation is showed in Fig. 2 while the blank holder force is 590kN.
在方程(1),F(xiàn)BHF是壓邊力(N);A是壓邊和空白的接觸面積(mm2);q是單位面積的壓邊力(MPA);在DYNAFORM,靜摩擦系數(shù)為0.125,沖壓速度是5000mm/s,凸模和凹模之間的間隙為1.1T(T是板材厚度),和下模固定不動(dòng)。進(jìn)行了數(shù)值模擬分析時(shí)分別壓邊力為四個(gè)數(shù)值:490kN,540kN,590kN,630kN。成形數(shù)值模擬中的極限圖是顯示在圖2中,壓邊力590kN。
從圖2可以看出,該部分燙金后不開(kāi)裂,但在邊緣發(fā)生起皺現(xiàn)象。這表明在這個(gè)位置使局部加厚材料的流動(dòng)是不充分的,這就是改進(jìn)過(guò)程的必要性。厚度的最大和最小部分是在浪費(fèi)區(qū),這對(duì)部分質(zhì)量無(wú)影響。最后,重點(diǎn)研究了零件沖壓后的有效面積,最大減薄率,最大增厚率等數(shù)據(jù)有效的是四種不同的壓邊力,如表1 。
從表1可以看出,最大減薄率逐漸增大,最大增厚率呈下降趨勢(shì),而壓邊力是增加的。這兩個(gè)參數(shù)是板帶產(chǎn)品質(zhì)量評(píng)價(jià)指標(biāo)后形成的,但他們無(wú)法表明板材成型后厚度的均勻度。因此,本文的特點(diǎn)是成形后板材厚度平均厚度偏差的均勻度。平均厚度為所有節(jié)點(diǎn)的厚度的平均值的數(shù)值模擬。平均偏差是指每個(gè)節(jié)點(diǎn)的平均厚度之間的絕對(duì)偏差的平均值,和平均偏差的數(shù)學(xué)表達(dá)式,它是用來(lái)反映各節(jié)點(diǎn)厚度的分散度,即板材厚度的均勻度。
從圖3可以看出,隨著壓邊力增加的部分,平均厚度逐漸減小,而平均偏差為逐步提高。這些部分正表明,每個(gè)節(jié)點(diǎn)的厚度分散度隨著壓邊力的增加而增加,而這部分的均勻成形后變得更糟。因此,滿足減薄和增厚的需求的情況下,我們可以選擇較小的壓邊力,提高在實(shí)際生產(chǎn)中形成均勻的部分后處理程序。
Influence of stamping speed on forming. Four programs of numerical simulation analysis in which stamping speed is respectively 4000mm/s, 4500mm/s, 5000mm/s, 5500mm/s were conducted to research the impact of stamping speed on part forming, when the BHF is 590kN. Some analysis data with four programs of numerical simulation are collated in Table 2.
沖壓速度對(duì)成形的影響。四數(shù)值模擬的分析程序中,沖壓速度分別為4000mm/s,4500mm/s,5000mm/s,5500mm/s進(jìn)行了研究沖壓速度對(duì)零件成形的影響,當(dāng)壓邊力是590kN。四的數(shù)值模擬程序的一些分析數(shù)據(jù)整理在表2。
正如從表2可以看出,沖壓速度的增加,最大減薄率呈現(xiàn)增加的趨勢(shì),在這個(gè)區(qū)間的峰值最大增厚。沖壓速度的增加,部分的平均厚度逐漸變厚的沖壓后。在低沖壓速度區(qū)間,平均偏差值較大時(shí),沖壓速度大,價(jià)值減少。說(shuō)明在高沖壓速度的條件下,沖壓后才能更好的均勻性。因此在實(shí)際生產(chǎn)中會(huì)變薄和增厚的需求的情況下,我們可以選擇處理程序具有較高的沖壓速度以提高形成根據(jù)沖壓設(shè)備的實(shí)際情況。
Influence of friction coefficient on forming. Four programs of numerical simulation analysis in which coefficient of friction is respectively 0.1, 0.125, 0.15, 0.175 were carried out in this paper when the stamping speed is 5000mm/s and the BHF is 590kN. The maximum thinning rate, maximum thickening rate and other date in the effective area are managed in Table 3.
摩擦系數(shù)對(duì)成形的影響。四數(shù)值模擬的分析程序中,摩擦系數(shù)分別為0.1,0.125,0.15,0.175進(jìn)行了當(dāng)沖壓速度5000mm/s和壓邊力是590kN。最大減薄率,最大增厚率等數(shù)據(jù)的有效面積是表3中的管理。
從表3可以看出,隨著摩擦系數(shù)的增加,最大減薄率呈下降趨勢(shì),而最大增厚率有一個(gè)谷值在這個(gè)區(qū)間值變化不大。隨著摩擦系數(shù)的增大,平均厚度部分逐漸減小,平均差逐步增大,均勻性和成形變差后。因此在實(shí)際生產(chǎn)中會(huì)變薄和增厚的需求的情況下,我們可以選擇具有較小的摩擦系數(shù),以提高零件的加工程序后形成的均勻性。
Influence of draw bead on forming. For this part, the two draw beads are respectively arranged on the upper and lower side of the die. The layout of draw bead is shown in Fig. 4. In Dynaform, the contact type select FPRMING_ONE_WAY_S_S. BHF is 590kN, Static friction coefficient is 0.125, the stamping speed is 5000mm/s, the clearance between punch and die is 1.1t, the down mold is fixed without moving. Under the above condition the forming limit diagram with draw bead and without draw bead are shown in Fig. 4.
拉延筋對(duì)成形的影響。對(duì)于這部分,兩拉延筋分別設(shè)置在模具的上部和下部。拉延筋的布置如圖4所示。在Dynaform,壓邊力是590kN,靜摩擦系數(shù)為0.125,沖壓速度是5000mm/s,凸模和凹模之間的間隙為1.1T,下模固定不動(dòng)的。在上述條件下的成形極限圖和拉延筋和無(wú)拉延筋,如圖4所示。
它可以明顯看出從圖5,安全區(qū)(圖中綠色)和拉延筋的程序比它的程序沒(méi)有拉延筋而其他參數(shù)相同。這表明拉延筋方案具有材料利用率和起皺的有效區(qū)域解除了更好的條件。因此,可以改善拉延成形過(guò)程中材料的利用。
和不同價(jià)值觀的過(guò)程參數(shù)的比較分析后,結(jié)合實(shí)際情況,最終的工藝參數(shù)如下:壓邊力是590kN,任何沖壓速度和靜摩擦系數(shù)為0.125,選擇了拉延筋的布置如圖4所示,最后形成的極限圖的數(shù)值模擬圖5(左)。與實(shí)際生產(chǎn)情況相比較,一致性好。
結(jié)論
(1) The thinning rate, thickening rate, stress and the strain distribution after stamping are the important indicators which characterize the forming quality. In the effective area, the maximum value of these indicators should be focused on. The uniformity degree of sheet after stamping can be characterized by the average thickness and the average deviation through data processing.
(1)減薄率,增厚率,應(yīng)力和應(yīng)變分布在沖壓是重要的指標(biāo)的特點(diǎn)成形質(zhì)量。在有效區(qū)域,這些指標(biāo)的最大值應(yīng)集中在。在沖壓的特點(diǎn)可以通過(guò)數(shù)據(jù)處理的平均厚度和平均偏差表的均勻度。
(2) Taking an automobile’s beam forming as an example, the impact of BHF, stamping speed, coefficient of friction and draw bead on forming quality of stamping was researched and the changing trend of the impact was analyzed in this paper. Finally the process parameters were determined combined with actual production situation. The result of numerical simulation has a great agreement with actual situation of production.
(2)以汽車的波束成形為例,對(duì)沖壓速度,壓邊力,摩擦和拉延成形質(zhì)量的影響進(jìn)行了研究和沖壓的變化趨勢(shì)進(jìn)行了分析系數(shù)。結(jié)合生產(chǎn)實(shí)際情況,確定最終工藝參數(shù)。數(shù)值模擬結(jié)果與生產(chǎn)實(shí)際情況,一個(gè)很好的協(xié)議。
(3) The impact of multi-factors on the stamping quality can be studied with analysis of stamping simulation. It can take place the repeated tryout in actual production to achieve the prediction and scientificity of stamping process plan, enhance the accurate and reliability of mold design and decrease the cycle of mold manufacturing and debugging, which has certain significance for the actual production.
(3)多因素對(duì)成形質(zhì)量的影響可以與沖壓成形仿真分析研究。它可以反復(fù)試模在實(shí)際生產(chǎn)中實(shí)現(xiàn)對(duì)沖壓工藝方案的預(yù)測(cè)和科學(xué)性的發(fā)生,提高模具設(shè)計(jì)的精度和可靠性,降低模具制造和調(diào)試周期,這對(duì)實(shí)際生產(chǎn)具有一定的指導(dǎo)意義。
參考文獻(xiàn)參考文獻(xiàn)
[1] Huang Yao, Zhu Qing, Wang Leigang, “Simulation on Multi-steps Stamping for Shock Absorber Lid Based on DYNAFORM” , Journal of Hot Working Technology, vol.40,no.15, pp.73-75, 2011.
1、黃耀,朱慶,王雷剛,“減震器端蓋多步?jīng)_壓成形仿真基于DYNAFORM”,熱加工工藝,雜志第40卷,第15號(hào),pp.73-75,2011。
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