CAJ | 학술논문

板料成形过程中工艺辅助面对成形件质量有着重要意义,但其设计非常费时,并且需要根据实验和数值模拟不断修正.本文提出一种工艺辅助面设计优化的方法.根据预期的工件形状,CAD软件会自动生成具有一阶连续的工艺辅助面.这些辅助面由4个几何参数确定并且在随后的优化中将其作为设计变量.有限元网格划分在有用工件和初始辅助面上,在优化过程中将这些网格映射到改变了的工艺辅助面上而不需要重新划分网格.优化过程中采用可行域二次序列规划算法(FSQP),并采用两个目标函数:第一个是厚度函数,以使工件厚度变化最小;第二个是表面质量目标函数,以避免工件外表面的擦伤.FSQP算法和我们的快速逆法成形求解器相结合而得到一个高效的优化程序.本文提出的辅助面设计优化方法在方盒件和减震器罩上得到了成功的应用.
판료성형과정중공예보조면대성형건질량유착중요의의,단기설계비상비시,병차수요근거실험화수치모의불단수정.본문제출일충공예보조면설계우화적방법.근거예기적공건형상,CAD연건회자동생성구유일계련속적공예보조면.저사보조면유4개궤하삼수학정병차재수후적우화중장기작위설계변량.유한원망격화분재유용공건화초시보조면상,재우화과정중장저사망격영사도개변료적공예보조면상이불수요중신화분망격.우화과정중채용가행역이차서렬규화산법(FSQP),병채용량개목표함수:제일개시후도함수,이사공건후도변화최소;제이개시표면질량목표함수,이피면공건외표면적찰상.FSQP산법화아문적쾌속역법성형구해기상결합이득도일개고효적우화정서.본문제출적보조면설계우화방법재방합건화감진기조상득도료성공적응용.
The addendum surfaces are very important for the product quality in sheet forming process, but their design is very time-consuming and requires tedious trial-error corrections. In this paper, a methodology is proposed for the design and optimization of addendum surfaces using a forming modelling solver. Starting with the desired workpiece,the addendum surfaces with C1 continuity are automatically generated. These surfaces are characterised by four geometrical dimensions, taken as the design variables in the optimization procedure. During the optimization, the finite element mesh created on the initial addendum surfaces is mapped onto the modified ones without remeshing operation.The Feasible Sequential Quadratic Programming (FSQP) is adopted as the optimization algorithm. Two objective functions are considered: the thickness function to minimize the thickness variation on the workpiece, the aspect function aiming to avoid the scratching defects. The FSQP is combined with our fast forming solver called" Inverse Approach"and this leads to a very efficient optimization procedure.