【作者】 戴亮；

【导师】 姚泽坤；

【作者基本信息】 西北工业大学 ， 材料加工工程， 2005， 硕士

【摘要】 在非对称高筋薄腹板复杂结构锻件的成形过程中,由于变形程度很大,金属流动情况异常复杂,容易产生回流、折叠等成形缺陷,因此对预制坯的体积分配、润滑以及模具的设计等要求很高。为了发现此类锻件成形过程中金属流动的规律,以及金属在型腔内的填充情况,本次试验采用等温成形的方法对“Z”字形、“Ч”字形、“H”字形截面复杂构件进行物理模拟研究,以优化毛坯尺寸、形状,探索出最优化的成形模具结构参数工艺。 通过铅、铝合金等材料对具有不同高宽比(局部最大高宽比为21:1)、非对称的并有“Z”、“Ч”、“H”字形截面的钛合金薄腹板(腹板厚仅为2.5mm)框结构件的等温成形过程的物理模拟发现,金属向半径增大的凸弧方向流动快于向半径减小的凹弧方向流动;使用非等宽度毛坯情况下,窄板处金属体积少,网格畸变严重。用铝合金模拟钛合金等温成形时,由于材料本身刚度大,流动性差,充填具有大高宽比筋的结构件需多次修整中间毛坯。成形后出模翘曲变形不明显,因此,用铝模拟钛合金等温变形更接近实际情况。更多还原

【Abstract】 For formation procedure of asymmetry aerofoil component with high rib and thin web, it is difficult to examine laws of fill pattern and laws of metal flow. The flaws can be brought if the die and billet are designed no correct, at the same time, it is also needed the well lubricate. In order to find the flow law of metal and metal’s filling capacity of these forging, the physical simulation tests are arranged.The isotherm formation physical modeling of unsymmetrical aerocraft frame part with Z, ч ,and H shape transverse section has been done with lead and LF21 aluminium alloy in this investigation. The results of modeling show the flow of metal toward convex arc to add radius is faster than flow of metal toward concave arc to decrease radius. The deformation of nets is very big at narrow location due to less metal here when same width rib was filled with different width billet. The more times defonnations is needed in filling rib with greater rate at height and width with LF21 aluminium alloy modeling. It makes the forming process be more approximate practical deformation of Titanium alloy. The theoretical and experimental foundation had been provided for determining the billet with appropriate shape and dimension, and the formation processing parameter by this experiment. About parameters of designing frame structural forming die have been providedsimultaneously.更多还原