發(fā)布時間：2018-08-17 19:22

【摘要】：隨著人們生活水平的不斷提高,汽車數(shù)量大幅增加,隨之而來的是交通事故頻發(fā)。汽車安全越來越受到人們的重視,而提高汽車的被動安全性是提高汽車安全的重要舉措也是汽車設(shè)計(jì)的關(guān)鍵環(huán)節(jié)。同時,為了節(jié)能減排,緩解能源危機(jī),汽車設(shè)計(jì)過程中應(yīng)當(dāng)兼顧汽車輕量化。一些新型的輕量化材料如：鎂合金、鋁合金、碳纖維等在提高汽車安全性和實(shí)現(xiàn)汽車輕量化方面體現(xiàn)出巨大的優(yōu)勢。雙帽型薄壁管是汽車車身中常用吸能元件,汽車碰撞過程中,尤其是側(cè)面碰撞時,吸能件經(jīng)常會發(fā)生彎曲變形,因此進(jìn)行雙帽型薄壁管橫向耐撞性能研究及輕量化設(shè)計(jì)具有重要的現(xiàn)實(shí)意義。本文首先進(jìn)行了鋼板和鎂合金的材料性能試驗(yàn),分別獲得了其應(yīng)力-應(yīng)變曲線。然后,設(shè)計(jì)了單一材料的鋼雙帽型管的準(zhǔn)靜態(tài)三點(diǎn)彎曲試驗(yàn),并進(jìn)行了有限元仿真模擬及對標(biāo)驗(yàn)證。通過有限元模擬分析了雙帽型管的吸能特點(diǎn),變形模式,研究了厚度對雙帽型管結(jié)構(gòu)耐撞性的影響規(guī)律,研究發(fā)現(xiàn)：在保證結(jié)構(gòu)質(zhì)量不變的情況下,合理搭配上帽和下帽的厚度能夠顯著改善雙帽型管的吸能能力。為了實(shí)現(xiàn)傳統(tǒng)的鋼雙帽型管的輕量化,引入了鎂合金雙帽型管。為研究其橫向耐撞性,對鎂合金雙帽型管進(jìn)行了準(zhǔn)靜態(tài)三點(diǎn)彎曲試驗(yàn),同時進(jìn)行了有限元仿真模擬及分析。結(jié)果顯示：鎂合金雙帽型管的變形模式和鋼雙帽型管大致相同,但是,鎂合金雙帽型管在受載時出現(xiàn)了局部斷裂,這種變形模式某種程度上限制了其吸能能力。為了研究鎂合金雙帽型管的輕量化效果,對鎂合金雙帽型管進(jìn)行了多目標(biāo)優(yōu)化,結(jié)果表明：鎂合金雙帽型管相比傳統(tǒng)的鋼雙帽型管體現(xiàn)出良好的輕量化優(yōu)勢,但是,要達(dá)到和鋼雙帽型管相同的吸能值,所需的結(jié)構(gòu)厚度太厚。由此,為了結(jié)合鋼雙帽型管良好的承載能力以及鎂合金雙帽型管的輕量化優(yōu)勢,引入了鋼-鎂混合雙帽型管,對兩種混合管進(jìn)行了準(zhǔn)靜態(tài)三點(diǎn)彎曲試驗(yàn)和有限元仿真分析,并以上帽和下帽的厚度為變量,并對混合管進(jìn)行了多目標(biāo)優(yōu)化。結(jié)果證明：無論從減重效果還是耐撞吸能方面,鋼／鎂混合管(上鋼下鎂管)的綜合表現(xiàn)都明顯優(yōu)于鎂／鋼混合管(上鎂下鋼管)。相比傳統(tǒng)的單一材料的雙帽型管,上鋼下鎂混合管綜合了鋼和鎂合金各自的優(yōu)勢,一方面可以明顯提高結(jié)構(gòu)的耐撞吸能能力,另一方面又具有良好的輕量化效果,所以上鋼下鎂混合管作為一種良好的耐撞性組件,可以在汽車車身上加以應(yīng)用。
[Abstract]:With the continuous improvement of people's living standards, the number of cars has increased significantly, followed by frequent traffic accidents. People pay more and more attention to automobile safety, and the improvement of passive safety is an important measure to improve vehicle safety, which is also the key link of automobile design. At the same time, in order to save energy and reduce emissions and alleviate the energy crisis, the automobile design process should take into account the automobile lightweight. Some new lightweight materials, such as magnesium alloy, aluminum alloy, carbon fiber and so on, have great advantages in improving automobile safety and realizing automobile lightweight. Double-cap thin-walled tube is a commonly used energy absorption element in automobile body. During the process of automobile collision, especially in side impact, the energy absorber will often be bent and deformed. Therefore, it is of great practical significance to study the lateral crashworthiness and lightweight design of double-cap thin-walled tubes. In this paper, the stress-strain curves of steel plate and magnesium alloy were obtained. Then, the quasi-static three-point bending test of steel double-cap tube with single material is designed, and the finite element simulation and calibration are carried out. The characteristics of energy absorption and deformation mode of double cap tube are analyzed by finite element simulation. The influence of thickness on the crashworthiness of double cap tube structure is studied. The thickness of upper cap and lower cap can improve the energy absorption ability of double cap tube. In order to lighten the traditional steel double cap tube, magnesium alloy double cap tube was introduced. In order to study the transverse crashworthiness of magnesium alloy double cap tube, the quasi-static three-point bending test was carried out, and the finite element simulation and analysis were carried out. The results show that the deformation mode of magnesium alloy double cap tube is approximately the same as that of steel double cap tube, but the strain mode of magnesium alloy double cap tube has a local fracture when it is loaded, which limits its energy absorption ability to some extent. In order to study the lightweight effect of magnesium alloy double cap tube, the multi-objective optimization of magnesium alloy double cap tube is carried out. The results show that the magnesium alloy double cap tube has a good lightweight advantage over the traditional steel double cap tube, but, To achieve the same energy absorption value as the steel double cap tube, the required thickness of the structure is too thick. Therefore, in order to combine the good bearing capacity of steel double cap tube and the lightweight advantage of magnesium alloy double cap tube, the steel-magnesium mixed double cap tube was introduced, and the quasi-static three-point bending test and finite element simulation analysis of the two kinds of hybrid tube were carried out. The thickness of the upper cap and lower cap is the variable, and the multi-objective optimization of the mixing tube is carried out. The results show that the comprehensive performance of steel / magnesium mixed pipe (upper steel and lower magnesium pipe) is obviously better than that of magnesium / steel mixed pipe (upper magnesium steel tube) in terms of weight reduction effect and energy absorption resistance. Compared with the traditional double cap tube with single material, the upper and lower magnesium mixed tube combines the advantages of both steel and magnesium alloy, on the one hand, it can obviously improve the energy absorption ability of the structure, and on the other hand, it has a good light weight effect. Therefore, as a good crashworthiness component, upper steel and lower magnesium mixed pipe can be used in automobile body.
【學(xué)位授予單位】：大連理工大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2016
【分類號】：U463.83

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 王超;王晨;呂振華;;帽形截面薄壁焊接結(jié)構(gòu)軸向耐撞性的優(yōu)化設(shè)計(jì)方法研究[J];汽車工程學(xué)報;2015年06期

2 彭金栓;徐磊;邵毅明;;汽車主動安全技術(shù)現(xiàn)狀及發(fā)展趨勢[J];公路與汽運(yùn);2014年01期

3 喬及森;許雪梅;茍寧年;陳劍虹;;薄壁方管吸能構(gòu)件準(zhǔn)靜態(tài)條件下軸向壓縮及三點(diǎn)彎曲大變形力學(xué)性能[J];塑性工程學(xué)報;2013年04期

4 亓昌;楊麗君;楊姝;;梯度鋁泡沫夾層結(jié)構(gòu)抗爆性能仿真與優(yōu)化[J];振動與沖擊;2013年13期

5 吳旭;王顯會;路先鋒;魏然;;基于自適應(yīng)響應(yīng)面法的薄壁構(gòu)件耐撞性優(yōu)化設(shè)計(jì)[J];機(jī)械設(shè)計(jì)與制造;2013年03期

6 陳吉清;黃信宏;周云郊;蘭鳳崇;;鋼鋁混合汽車前縱梁的耐撞性優(yōu)化方法比較[J];華南理工大學(xué)學(xué)報(自然科學(xué)版);2012年07期

7 武雪原;夏勇;周青;;Influence of flange location on axial deformation stability of double-hat structure[J];Journal of Beijing Institute of Technology;2012年01期

8 涂志軍;徐會波;;汽車電子技術(shù)的應(yīng)用與發(fā)展研究[J];科技資訊;2012年05期

9 牛建輝;朱平;;高強(qiáng)鋼閉口帽形結(jié)構(gòu)準(zhǔn)靜態(tài)軸向壓潰實(shí)驗(yàn)[J];上海交通大學(xué)學(xué)報;2011年11期

10 趙福全;吳成明;潘之杰;劉衛(wèi)國;劉巍;;中國汽車安全技術(shù)的現(xiàn)狀與展望[J];汽車安全與節(jié)能學(xué)報;2011年02期

相關(guān)會議論文 前1條

1 劉大學(xué);孫振平;安向京;賀漢根;;汽車主動安全的發(fā)展及未來[A];中國汽車工程學(xué)會汽車電子技術(shù)分會第七屆（2006）年會暨學(xué)術(shù)研討會論文集[C];2006年

相關(guān)博士學(xué)位論文 前1條

1 周云郊;鋼鋁混合材料車身結(jié)構(gòu)輕量化設(shè)計(jì)關(guān)鍵問題與應(yīng)用研究[D];華南理工大學(xué);2011年

相關(guān)碩士學(xué)位論文 前3條

1 胡海濤;帽型薄壁梁抗彎性能研究及多目標(biāo)優(yōu)化[D];大連理工大學(xué);2015年

2 關(guān)曉潔;鋼鋁混合結(jié)構(gòu)前縱梁耐撞性仿真研究[D];湖南大學(xué);2013年

3 葉靈東;基于行人頭部和下肢綜合防護(hù)的汽車前部結(jié)構(gòu)參數(shù)研究[D];湖南大學(xué);2009年

，

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