摘要:本文以烧烤炉内板作为研究对象,采用模拟软件dynaform进行拉深模拟。本文主要以减薄率作为判断板料成形性能的指标,研究内容主要有两点,一是研究常压边力、变压边力以及分区压边力对深锥形件成形性能的影响;二是研究在第一次拉深中采取不同的压边力对第二次拉深造成的影响。研究的方法是通过改变压边力大小或者加载模式,观察并分析该板料在拉深后的拉深极限图、厚度分布图以及最小壁厚和最大减薄率等来比较不同压边力加载模式对该板料拉深的影响。模拟结果发现在常压边力的模拟中,压边力为62.5KN下拉深后的最大减薄率比在67.5KN下拉深的最大减薄率小4.445%;采取斜率由大变小的下降型变压边力可以使减薄率减少3.770%;采取三段分区压边力的减薄率最高要比两段分区压边力的减薄率小2.615%。并且在第一次拉深中的压边力为67.5KN的样品在第二次拉深中的减薄率和不稳定性要比在第一次拉深中压边力为62.5KN的样品要高。这说明采取下降型的、斜率先大后小的变压边力方案,以及较多分区的分区压边力对该产品的成形性能的改善程度较高;在第一次拉深成形中采取较小的压边力更有利于第二次拉深成形。
关键词:压边力;深锥形件;dynaform;拉深
Abstract:In this paper, taking the grill inner plate as the object of study, the DYNAFORM is used for deep drawing simulation. The thinning rate is used to evaluate the formability of sheet. The main research concludes two points: the effect of constant blank holder force, variable blank holder force and pide blank holder force on the formability of cone parts; the effect of taking different blank holder force in the first drawing on the second drawing. Changing blank holder force or loading mode to observate the drawing limit diagram and the thickness distribution diagram, and analyze the minimum wall thinning and the maximum wall thinning, which mean to compare the effects of different blank holder force on drawing. The result shows: the thinning rate under 62.5KN is 4.445 percent lower than the thinning rate under 67.5KN; the thinning rate can be reduced by 3.770 percent by taking variable blank holder force which the force and slope are decreased; the thinning rate of which blank holder is pided into three parts is 2.615 percent lower than the thinning rate of which blank holder is pided into two parts. At the same time, the thinning rate and instability of which blank holder force is 62.5KN are lower than which blank holder force is under 67.5KN in the second drawing. It shows that decreased force and slope, variable blank holder force will improve the formability of the product, and more regions devided can improve it too.Taking lower blank holder force is more conducive to the second drawing in the first drawing.
Keywords: blank holder force; deep cone parts; dynaform; deep drawing;
目录
第一章绪论 1
1.1 研究背景 1
1.3 本文主要内容 5
第二章有限元模型的建立 6
2.1 DYNAFORM软件简介 6
2.2 深锥零件拉深方案 6
2.3 数值模型的建立 7
2.4 相关参数和模拟条件的设置 9
第三章不同压边力加载模式模拟结果及分析