THE INFLUENCE OF ZIRCONIUM ON IRON AND STEEL (I)

Abstract

In foreign countries, the influence of zirconium on iron and steel was studied quite a considerable time: the results were put to practical use. but, in Japan, there are few published systematic studies about this influence of zirconium, in fact, still many unknown points about the effects of zirconium and no commercial uses of it.
The author has studied about this problem since 1941 and reports on this essay I, the influence of a small amount of zirconium on iron and steel, mostly, the results of elemental studies in laboratory scale.
The results of these experiments are summerized as follows.
(1) Commercial zirconium mother alloy of differentiated methods of preparation in assortment, chemical composition, action and yield in melting were tested.
(2) When a small amount of zirconium is added into steel, blowholes in ingot can be reduced and sound ingot gotten, and oxygen and nitrogen contents in ingot can be reduced. The degree of deoxidizing action is stronger than silicon and pretty weaker than aluminium. Zirconium greatly reduces the percentage of acid-soluble nitrogen in an ordinary steel.
(3) Pretty clean steel can be obtained with moderate treatments and many characteristic inclusions are recognized in zirconium-treated steel. Compositions and forms of these inclusions were studied.
(4) Desulphurising capacity of zirconium is stronger than manganese and the maximum value of desulphurisation percentage was 65%.