Intriguing uniform elongation and accelerated radial shrinkage in an amorphous SiOxnanowire as purely induced by uniform electron beam irradiation

The nanowire demonstrates a tensile pulling-free uniform plastic elongation and an accelerated radial shrinkage at nanoscale under uniform e-beam irradiation.

Springback Angle and Plastic Elongation Prediction of Thin-Walled Tube Bending by FEM

Springback is an inevitable phenomenon while the load is released due to the elastic property after tube bending. This leads to an increase in the radius of curvature and elongation by plastic deformation, a reduction in the bending angle of the bent tube, a decrease in dimensional accuracy and fits with others difficulty. By elastic–plastic finite element methods (FEM), a reasonable simulation model for thin-walled tube bending is established to define the relationships between process parameters and springback angle, plastic deformation. With 210 kinds of models, the results show that: 1) Springback angle and plastic elongation of bending tube are related to bending angle, bending die diameter and tube thickness. 2) Controlling functions for plastic elongation and springback angle in bending tube process are given, which is verified by tube bending experiments.

Prediction of Bend Allowance and Springback in Air Bending

In the fabrication industry, one of the critical challenges is to maintain close geometric tolerances in finished products, particularly in the air bending process. In many cases, this problem is related to springback and plastic elongation/compression of the sheet, as it undergoes deformation in bending. Springback refers to the elastic recovery of the bent sheet after unloading, whereas bend allowance refers to the elongation of the sheet during bending. Both factors, if not predicted properly, may lead to dimensional inaccuracies in the finished product and cause difficulties in the assembly. Therefore, it is essential to predict springback and bend allowance in order to obtain the final desired geometry. A new analytical model was developed to predict springback and bend allowance simultaneously in air bending, and a user-friendly computer program, BEND (Version 3.0), was developed. Results obtained from the BEND program were compared to other analytical predictions and experimental results available in the literature. It was concluded that the proposed analytical model and the computer program predicted bend allowance and springback within acceptable accuracy.