Reference - A novel method of determining residual stress distributions in plates using the incremental slitting technique
| Type | Journal |
|---|---|
| Title | A novel method of determining residual stress distributions in plates using the incremental slitting technique |
| Abstract | A method is described to determine residual stress distributions in homogeneous plates from strain measurements obtained using the incremental slitting method, which is modelled using a linear thermo-elastic analysis originally developed for anisotropic multipleply laminates having arrays of equally spaced ply cracks. A linear thermo-elastic analysis, for the special case where the plate is homogeneous and isotropic, is used within an inverse modelling problem to interpret measured strains, obtained by gradually slitting the plate and measuring strain changes on the external surface during bend deformation, in terms of distributions of residual stress. The model has been used to estimate the residual stress distributions within polypropylene-based samples, including samples with untreated and aminosilane-treated glass flakes. In the internal region of the plate, the residual stress distribution can be estimated reliably as results do not depend on the parameters used for the analysis. Results of predictions near the cut free surface show some variability, which is thought to be attributable to the insensitivity of strain measurements to the length of the slit. To overcome this problem it is recommended that a plate is slit from both free surfaces at different widely spaced locations. Comparisons of the calculated strains with the original smoothed experimental input data showed very close agreement, indicating that the linear thermo-elastic model is appropriate for these samples. |
| Authors |
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| Date | 2011 |
| Issue | 4 |
| Pages | 280-297 |
| Journal | Journal of Strain Analysis for Engineering Design |
| Volume | 46 |
| Websites | |
| DOI | 10.1177/0309324711399683 |
| ISSN | 03093247 |
| Keywords | Bend deformations, Bending (deformation), Crystallography, External surfaces, Free surface, Inverse p, Residual stresses |
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Interrelationship of Function, Shape, Material & Process
Design for manufacturing is critical to ensuring the producibility of a part. Trouble arises when it is considered too late or not at all in the design process. Conversely, process design (controlling the interactions between shape, material, tooling & consumables and equipment to achieve a desired outcome) must always consider the shape and material of the part. Ashby has developed and popularized the approach linking design (function) to the choice of material and shape, which influence the process selected and vice versa, as shown below:
Within the Knowledge in Practice Centre the same methodology is applied but the process is more fully defined by also explicitly calling out the equipment and tooling & consumables. Note that in common usage, a process which consists of many steps can be arbitrarily defined by just one step, e.g. "spray-up". Though convenient, this can be misleading.
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