摘要
随着高速铣削中材料的去除,毛坯初始残余应力的释放必将引起飞机整体结构件的加工变形。分析具有初始几何误差的毛坯初始残余应力释放造成的加工变形是控制加工质量的核心,对于实现加工过程的精密化至关重要。建立加工变形的力学模型及其相应的有限元方法,揭示毛坯初始几何误差对零件变形的影响规律。以最小变形为目标建立加工位置的优化模型,根据相邻两个加工位置的增量不超出阈值这一条件,提出优化模型的步长递减算法。计算结果表明:无论变形趋势还是幅值,三框整体结构件加工变形的模型计算值、有限元仿真值与试验结果均非常吻合;毛坯有初始几何误差与无初始几何误差两种情况下,三框整体结构件的最佳加工位置分别为22.7543 mm和23.265 mm,相应的零件变形值分别为-0.006 mm和-0.007 mm;毛坯无初始几何误差时,零件在位置22.7543 mm处的变形为0.043 mm;毛坯有初始几何误差时,零件在位置23.265 mm处的变形则为-0.144 mm;所得结果进一步验证了毛坯初始几何误差对零件变形具有极大影响。
In the process of high-speed milling,the release of initial residual stress will cause the machining deformation of aeronautical monolithic component.The machining deformation caused by the initial residual stress release of blank with initial geometric error should be analyzed to control the machining quality,which is very important for the precision machining process.A mechanical model of machining deformation and a finite element method are established to reveal the influence of the initial geometric error of blank on the workpiece deformation.An optimization model of machining position is established with the minimum deformation as the objective.According to the condition that the increment of two adjacent machining positions does not exceed the threshold,a step decreasing algorithm of the optimization model is proposed.The results show that the model calculated values are in good agreement with both the finite element simulated values and the experimental results whether in deformation trend or amplitude.When the blank has initial geometric error or no initial geometric error,the optimal machining positions of the three-frame integral structure are 22.7543 mm and 23.265 mm,and the corresponding deformation values are-0.006 mm and-0.007 mm,respectively.When the blank has no initial geometric error,its deformation at the position of 22.7543 mm is 0.043 mm,and when the blank has initial geometric error,its deformation at the position of 23.265 mm is-0.144 mm.It is further verified that the initial geometric error of the blank has a great influence on its deformation.
作者
林锋
姚婉
秦国华
叶海潮
陶江
LIN Feng;YAO Wan;QIN Guohua;YE Haichao;TAO Jiang(School of Aeronautical Manufacturing Engineering,Nanchang Hangkong University,Nanchang 330063,Jiangxi,China)
出处
《兵工学报》
EI
CAS
CSCD
北大核心
2021年第12期2731-2742,共12页
Acta Armamentarii
基金
国家自然科学基金项目(51765047)
江西省主要学科学术和技术带头人计划项目(20172BCB22013)
江西省科技厅重点研发计划项目(20203BBE53049)。
关键词
飞机整体结构件
初始残余应力
初始几何误差
加工变形
加工位置
步长递减算法
aeronautical monolithic component
initial residual stress
initial geometric error
machining deformation
machining position
step decreasing algorithm