【摘要】：Al-Zn-Mg-Cu合金由于其輕質(zhì)、高比強度、抗腐蝕性能好、易成形和可焊接等優(yōu)點,越來越受到航空航天、國防軍工、武器裝備等領(lǐng)域?qū)＜覍W者和技術(shù)人員的青睞,其在國防領(lǐng)域的成功應用同樣引起了汽車等民用工業(yè)行業(yè)的廣泛關(guān)注,越來越多的汽車覆蓋件及整車框架已逐步開始試用這類鋁合金。擺動輾壓工藝是通過連續(xù)局部塑性變形來使工件獲得所需形狀尺寸的回轉(zhuǎn)成形加工工藝,適用于薄盤類和法蘭類零件的成形。它具有省力、節(jié)材、沖擊振動噪聲小、產(chǎn)品精度高、投資少等諸多技術(shù)及經(jīng)濟方面的優(yōu)點,在車輛、機械、電器儀表及輕工五金業(yè)得到了快速發(fā)展和廣泛的應用。本文結(jié)合擺動輾壓成形工藝,對新型Al-Zn-Mg-Cu合金杯形件成形進行探究。首先,利用Deform-3D軟件對該類杯形件三種成形方案進行數(shù)值模擬,結(jié)果表明:該類杯形件擺輾成形載荷分別是擠壓成形和壓扭成形的1/4和2/5,省力效果非常明顯。同時,對杯形件擺輾成形的成形過程、等效應變場分布、金屬流動、成形截面網(wǎng)格變化及變形區(qū)分布、損傷場進行分析,結(jié)果表明:杯形件擺輾成形主要分為三個階段,等效應變呈M型梯度變化,杯形件擺輾成形損傷值相對較小,成形效果好。隨后,研究不同坯料高徑比及始輾溫度對成形效果的影響,結(jié)果顯示:最佳坯料高徑比為1.0,始輾溫度390℃。在數(shù)值模擬基礎(chǔ)上,進行不同坯料高徑比及工藝的物理實驗,結(jié)果顯示:杯形件擺輾成形無論從晶粒尺寸還是力學性能上均優(yōu)于擠壓及壓扭成形。最后,結(jié)合擺輾杯形件存在問題,提出了往復擠壓工藝制坯方案,結(jié)果顯示:經(jīng)往復擠壓后的材料塑性顯著提升,組織及力學性能也得到較大優(yōu)化。本文通過一系列研究,成功試制出符合成形要求的杯形件,同時結(jié)合實際問題,提出往復擠壓制坯工藝,為后續(xù)該類材料杯形件更大批量的制造及更高服役條件的需求打下堅實的理論和實踐基礎(chǔ)。
[Abstract]:Because of its advantages of light weight, high specific strength, good corrosion resistance, easy forming and weldability, Al-Zn-Mg-Cu alloy is more and more favored by experts and technicians in the fields of aerospace, national defense and military industry, weapons and equipment, etc. Its successful application in the field of national defense has also attracted wide attention in the field of automobile and other civil industries. More and more automobile panels and vehicle frames have gradually begun to use this kind of aluminum alloy. Swing forging is a kind of rotary forming process which can make the workpiece obtain the required shape and size by continuous local plastic deformation. It is suitable for forming thin disk and flange parts. It has many advantages in technology and economy, such as saving labor, saving materials, low impact vibration and noise, high precision of product, less investment, etc. It has been rapidly developed and widely used in the field of vehicle, machinery, electrical instrument and light industry hardware. In this paper, a new type of Al-Zn-Mg-Cu alloy cup forming process is studied. Firstly, the numerical simulation of the three forming schemes of this kind of cup parts is carried out by using Deform-3D software. The results show that the forming load of this kind of cup is 1 / 4 and 2 / 5 of that of extrusion forming and pressing and torsion forming, respectively, and the effect of saving force is very obvious. At the same time, the forming process, the distribution of equivalent strain field, metal flow, the change of forming section mesh and the distribution of deformation zone and damage field are analyzed. The results show that the forming process of cup forming is mainly divided into three stages. The equivalent strain varies with M-type gradient, and the damage value of cup forming is relatively small, and the forming effect is good. Then, the influence of different ratio of height to diameter of billet and temperature of initial rolling on forming effect was studied. The results showed that the optimum ratio of height to diameter of blank was 1.0 and the initial rolling temperature was 390 鈩，

本文編號：2425952