摘要
针对板材在单点渐进成形过程中受力不均匀,容易出现失稳,并产生堆积、起皱、破裂等缺陷。若将振动技术引入到这种工艺,其成形机理将发生变化,板材加工的质量也将得到提高。因此,通过对工具头局部成形区域的单元体进行分析,建立力学方程。根据板材塑性成形过程中的拉应力与剪应力关系的假设,可以得到力学方程的近似解。按照给定的工艺参数、材料的机械性能参数和振型参数可以得到相关的应力曲线。模拟实验分析表明,在施加振动后,单点渐进成形过程中的应力发生了显著变化;在相同成形角的条件下,与低频振动相比,高频振动对成形应力的影响更加明显;但在低频振动条件下,存在成形角度条件;在高频振动条件下,存在频率条件。
As a non-homogenous force stresses during incremental forming,sheet metal easily tends to instability,and some defects,such as deposition,wrinkle and fracture,will appear.If the vibration technique is introduced to the incremental forming process,deformation mechanism will be different from that of the old process,and sheet metal deformation quality is also improved.Mechanical equations are built by force analysis on element in local contact zone of die head forcing down.According to the hypothesis between tensile stress and shear stress relationship during sheet metal forming,a similar solution of the equations can be obtained.With technological parameters,mechanical performance parameters and vibrational parameters given,some stress curves are obtained.It is shown from simulation experiment that the sheet metal stress has prominent variation during incremental forming with vibration;and effect of forming stress with high frequency vibration is better than that of the low frequency vibration on the condition that the forming angle is the same;and the vibration incremental forming should meet the condition of deformation angle with low frequency or meet the condition of frequency with high frequency.
出处
《机械科学与技术》
CSCD
北大核心
2010年第7期915-920,共6页
Mechanical Science and Technology for Aerospace Engineering
基金
国家自然科学基金项目(50975131)资助
