TITLE:
Investigation into the Deep Drawability of 0.1%C Eutectoid Steel
AUTHORS:
Samson Oluropo Adeosun, Olatunde Israel Sekunowo, Sanmbo Adewale Balogun
KEYWORDS:
Eutectoid Steel; Drawability; Annealing; Cupping; Anistropism
JOURNAL NAME:
Journal of Minerals and Materials Characterization and Engineering,
Vol.11 No.10,
October
31,
2012
ABSTRACT: The phenomenon of anisotropism in most rolled products necessitates that the rolling direction that enhances desirable mechanical property is established. In this paper, the comparative deep drawability of as-received and annealed mild steel containing about 0.1%C was investigated. The flat steel sample was divided into two and classified as as-received and heat treated respectively. The heat treated sample was obtained by annealing at 950°C after been soaked for 5 hours and deep drawn at ambient temperatures (35°C - 42°C). From both samples, circular specimens were machine- blanked parallel to the rolling directions inclined at 0°, 45° and 90° respectively and were prepared for deep drawability test while rectangular specimens were prepared for tensile test. Both specimens, as-received and annealed were then sub- jected to tensile, cupping and microstructural analyses. Results show that the contribution to increased formability at 90° rolling direction seems to have come from the spheroid-like pearlite grains induced during annealing while the sta- bility of spread observed was achieved through a modest increase in strength. Thus, the resistance of annealed eutectoid steel to cupping is quite minimal at 90° to the rolling direction. The desirable drawability characteristics developed by the annealed eutectoid steel specimen are: cup-height, 30 mm maximum and ear, 6.4% maximum.