抄録
Kohei Taniguchi By the investigation of the characteristics of ateel mill chilled rolls for the object of improving their propertie, all the results of experiments tried until present on common cast irons are shown to be unsuitable for chilled rolls owing to the remarbkable difference in their properties. So the author deveced a prorer apparatus for this object to study this problem by reasonable method, and gained the following results.
(1) Influences of fifteen elements, namely, C, Al, Si, P, Ti, Co, Ni, Cu, S, V, Cr, Mn, Mo, Sn, W, are investigated in very wide rangest upon the surface hardness and the depth of chill which are so important for all chilled rolls, and are found to be most effective to add nickel with a little amount of chromet to gain hard rolls among those elements.
(2) In copsequence of the above resulte, various effects of nickwl and ohrome, and also combind effects of both elements were again further studied respectively, not only on surface problems but also on many physical and mechanieal properties of the inner grey part of the roll, and at last a very hard and strollg alloy chilled roll was invented, whose chemical composition lies between Ni 3.3, Cr 1.2%-Ni 4.3, Cr 1.6% and has its surface hardness oyer 90 in sclercope number, keeping always a constant chill depth equal to ordinary chilled rolls.
(3) Furthermore a plenty of this kind of heavy rolls has been practically cast in our foundry since that time, and used as tin plate finishing rolls (weight of one roll is 3, 800kg) or thin sheet finishing rolls(weght of one roll is 5, 717kg)act, for these several years gaining a splendid reaulta beyond expeutation.
