A Consideration on "Greyness" of Tin Plates

Abstract

Synopsis:Greyness of tin plates which were manufactured from semi-killed steel ingots was investigated. The authors could not find the influence of Cr, Ni, and Cu ordinally included in normal raw materials.The appearance of the defects was studied mainly by the microscopic examination and it was whether greyness in rimmed tin plates had the similar oxide layer or not, and the existence of that oxide was clarified. Finally, the differenoe of oxidizing degree of various low carbon steel was studied by annealing test, and the knowledge of the effect of chemical composition on oxidizing was examined.In conclusion, it was confirmed that the very existence of the thin oxide layer was the most important and direct causes of greyness.