基于細觀損傷的7075鋁合金HFQ溫?zé)岢尚涡阅苎芯?/H1>
發(fā)布時間：2019-05-17 05:37
【摘要】：近年來,汽車行業(yè)的飛速發(fā)展帶來了能源大量消耗的問題。生產(chǎn)出安全且節(jié)能環(huán)保型汽車成為了汽車產(chǎn)業(yè)發(fā)展的主題。實現(xiàn)這一目標(biāo)的有效方法之一是汽車輕量化技術(shù)。在確保穩(wěn)定提升汽車強度和安全性能的基礎(chǔ)上最大限度的減輕汽車的質(zhì)量,設(shè)計出質(zhì)量輕且節(jié)能安全的零部件從而提高汽車的動力性,極大的減輕燃料的消耗以滿足當(dāng)代人們對汽車的要求。鋁合金材料密度低,比強度高,是理想的輕質(zhì)工程材料。然而,運用傳統(tǒng)的鋁合金溫成形工藝,樣件成形后容易產(chǎn)生回彈變形。因此在傳統(tǒng)的溫成形工藝基礎(chǔ)上,出現(xiàn)了新型的鋁合金溫成形技術(shù),即溫?zé)岢尚?淬火一體化工藝(Solution Heat treatment-Forming-Cold Die Quenching),簡稱HFQ成形技術(shù)。該工藝在提高鋁合金成形性能的基礎(chǔ)上,可以有效降低成形件回彈,獲得較好的力學(xué)性能。材料成形過程中從變形開始直至破壞是一個逐漸劣化的過程,材料內(nèi)部結(jié)構(gòu)不可避免地存在初始損傷和各種缺陷,例如微裂紋、微孔洞的等缺陷的存在。由于GTN細觀損傷模型考慮了材料內(nèi)部的損傷,其表征材料內(nèi)部損傷演化的各個參數(shù)都具有明確的物理涵義,將GTN細觀損傷模型引入到金屬板材數(shù)值成形仿真技術(shù)中,可以更有效的幫助我們研究損傷對于材料成形的影響。GTN模型中損傷參數(shù)的準(zhǔn)確確定成為了相關(guān)研究的關(guān)鍵因素之一。圍繞上述問題,本文首先對7075鋁合金的基本力學(xué)性能進行了研究,在25℃-475℃溫度范圍內(nèi),0.01s-1應(yīng)變速率條件下完成單向熱力拉伸實驗。通過熱拉伸試驗獲取材料的基本力學(xué)性能。將獲得的基本力學(xué)性能數(shù)據(jù)整理并應(yīng)用到基于GTN模型的ABAQUS仿真軟件中建立單拉模型。采用單向拉伸數(shù)值模擬—響應(yīng)曲面優(yōu)化—遺傳算法確定GTN參數(shù)。為了獲取準(zhǔn)確的細觀損傷參數(shù),本文通過實驗和數(shù)值仿真的方法,研究了基于GTN損傷模型的鋁合金板材在HFQ工藝條件下的溫?zé)岢尚涡阅堋＝Y(jié)合深沖盒模具研究了細觀損傷對于板材成形性能的影響。結(jié)果表明:初始成形溫度、壓邊力都對成形有重要的影響。升高初始成形溫度,有效的改善了7075鋁合金的成形性能。在相同溫度下,壓邊力的增大使得鋁合金的成形性能顯著降低�；贕TN模型的數(shù)值仿真結(jié)果與實際實驗結(jié)果趨勢相同。相關(guān)研究成果可為后續(xù)的鋁合金溫成形性能數(shù)值仿真研究及工藝優(yōu)化提供理論支撐。
[Abstract]:In recent years, the rapid development of the automobile industry has brought about a large number of energy consumption problems. The production of safe, energy-saving and environment-friendly cars has become the theme of the development of the automobile industry. One of the effective ways to achieve this goal is automobile lightweight technology. On the basis of ensuring the stable improvement of the strength and safety performance of the vehicle, the quality of the vehicle can be reduced to the greatest extent, and the light weight and energy saving and safe parts are designed to improve the power performance of the automobile. Greatly reduce fuel consumption to meet the requirements of contemporary people for cars. Aluminum alloy is an ideal lightweight engineering material because of its low density and high specific strength. However, by using the traditional warm forming process of aluminum alloy, the springback deformation is easy to occur after the sample is formed. Therefore, on the basis of the traditional warm forming process, a new type of thermoforming technology for aluminum alloy has emerged, that is, the integrated warm forming and quenching process (Solution Heat treatment-Forming-Cold Die Quenching), referred to as HFQ forming technology. On the basis of improving the formability of aluminum alloy, this process can effectively reduce the springback of forming parts and obtain better mechanical properties. In the process of material forming, it is a gradual deterioration process from the beginning of deformation to the destruction. The internal structure of the material inevitably has initial damage and various defects, such as microcracks, micropores and so on. Because the GTN meso-damage model takes into account the internal damage of the material, and each parameter describing the damage evolution of the material has a clear physical meaning, the GTN meso-damage model is introduced into the numerical forming simulation technology of sheet metal. It can help us to study the effect of damage on material forming more effectively. The accurate determination of damage parameters in GTN model has become one of the key factors in related research. Focusing on the above problems, the basic mechanical properties of 7075 aluminum alloy were studied in this paper. The unidirectional thermal tensile test was completed in the temperature range of 25 鈩，
本文編號：2478846
本文鏈接：http://sikaile.net/kejilunwen/jiagonggongyi/2478846.html
[Abstract]:In recent years, the rapid development of the automobile industry has brought about a large number of energy consumption problems. The production of safe, energy-saving and environment-friendly cars has become the theme of the development of the automobile industry. One of the effective ways to achieve this goal is automobile lightweight technology. On the basis of ensuring the stable improvement of the strength and safety performance of the vehicle, the quality of the vehicle can be reduced to the greatest extent, and the light weight and energy saving and safe parts are designed to improve the power performance of the automobile. Greatly reduce fuel consumption to meet the requirements of contemporary people for cars. Aluminum alloy is an ideal lightweight engineering material because of its low density and high specific strength. However, by using the traditional warm forming process of aluminum alloy, the springback deformation is easy to occur after the sample is formed. Therefore, on the basis of the traditional warm forming process, a new type of thermoforming technology for aluminum alloy has emerged, that is, the integrated warm forming and quenching process (Solution Heat treatment-Forming-Cold Die Quenching), referred to as HFQ forming technology. On the basis of improving the formability of aluminum alloy, this process can effectively reduce the springback of forming parts and obtain better mechanical properties. In the process of material forming, it is a gradual deterioration process from the beginning of deformation to the destruction. The internal structure of the material inevitably has initial damage and various defects, such as microcracks, micropores and so on. Because the GTN meso-damage model takes into account the internal damage of the material, and each parameter describing the damage evolution of the material has a clear physical meaning, the GTN meso-damage model is introduced into the numerical forming simulation technology of sheet metal. It can help us to study the effect of damage on material forming more effectively. The accurate determination of damage parameters in GTN model has become one of the key factors in related research. Focusing on the above problems, the basic mechanical properties of 7075 aluminum alloy were studied in this paper. The unidirectional thermal tensile test was completed in the temperature range of 25 鈩，
本文編號：2478846
本文鏈接：http://sikaile.net/kejilunwen/jiagonggongyi/2478846.html
最近更新
教材專著
