Optimisation of structure and texture of tinplate for easy-opening can ends
- J. Gil Sevillano 2
- C. García-Rosales 2
- C. Torrente 1
- M. A. Arias 1
- M. Rettagliata 3
- C. Sciaboni 3
- R. Sauer 4
- K. Stein-Fechner 4
- 1 Aceralia, Apartado 90, E-33480 Avilés (Asturias)
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2
Centro de Estudios e Investigaciones Técnicas de Gipuzkoa
info
Centro de Estudios e Investigaciones Técnicas de Gipuzkoa
San Sebastián, España
- 3 CSM, Via di Castel Romano, 100, I-00128 Rome
- 4 Rasseistein-Hoesch, Koblenzestrabe 141, D-56625 Andernach
ISSN: 0256-7121
Año de publicación: 2002
Tipo: Informe
Otras publicaciones en: Official Publications of the European Communities
Resumen
A wide range of standard tinplate qualities currently used for EOE production, including two DR tinplate qualities, have been studied and their EOE performance has been correlated with their mechanical and textural properties. The study has also been extended to an Al alloy and to several non-EOE steel sheets. Numerical simulations of the easy-opening process have been performed in parallel with the experimental tests. The main results of the project are as follows. - A high strength and a low ductility are both beneficial for lowering the maximum tear force of a pre-cracked scored tinplate EOE. DR tinplate grades are excellent for the application. Maximum tearing forces equal to or lower than the forces needed in the opening of aluminium ends of similar geometry have been measured with tinplate steel. - The role of crystallographic texture on EOE performance has been explored but no benefit from it has been found within the textures found in materials of interest for the canning industry. - Highly realistic numerical predictions of the EOE opening process have been made by two of the project partners using two different commercial codes. Both studies coincide in the paramount importance of mode III 'essential work of fracture' (the work spent in cracking the score residual section) on EOE performance of a material, and, in particular, in the determination of the maximum tearing force in the opening process. It seems to be the only fracture parameter needed for simulation, the other material parameters being the elastic-plastic properties of the sheet. Only the tear force needs more material parameters for a good quantitative prediction. - The 'essential work of fracture' of scored sheets can be measured using two-leg straight-scored specimens. lt is a parameter used in fracture mechanics for characterising the fracture of thin sheet ductile materials. For the tinplate materials, its value ranges from 20 to 60 KJm-2 (work of fracture per unit surface of crack advance).