Analysis of the limit strains of coated sheet steel for different strain paths

✍ Scribed by Jerzy Gronostajski; Waleed Jalal Ali; Magdy Samuel Ghattas

• Publisher: Elsevier Science
• Year: 1990
• Tongue: English
• Weight: 410 KB
• Volume: 22
• Category: Article
• ISSN: 0924-0136
• DOI: 10.1016/0924-0136(90)90036-t

✦ Synopsis

The FLDs for linear and complex strain paths have been determined experimentally for polyethylene-, acryl-and PVC-coated steel sheets. Each material has been studied under three conditions: as received; coated with zinc after the removal of the plastic layer; and as bare steel after the removal of all coatings. The complex strain paths were carried out in such way, that in the first step of deformation the specimens were in the in-plane condition and during the second step in the out-of-plane condition. As a result of the investigations performed, it was ascertained that the forming limit curves, their position and their shape obtained for different strain paths, depend on the kind of coating. It can be stated that, in general, coatings improve the formability: the effect of the acryl coating is less than that of the polyethylene, whilst the polyethylene effect is less than that of the PVC. A zinc coating gives the least effect. The improvement of the formability of steel sheet depends on the coefficient of friction between the tools and the sheet steel.