Research on the High Silicon Malleable Cast Iron by the Addition of Bismuth

High silicon malleable cast iron was manufactured by adding 0.05 per cent of bismuth. The mechanical properties of this iron are better, and the periods of malleablized heat treatments are shorter than those of conventional malleable cast irons. The chilling tendency caused by the addition of bismuth begins to fade in 5 minutes after its addition to a molten iron

Studies of the Quality, Relaxation and Wear Resisting Properties of Vanadium High Grade Cast Iron

We studied Relative Harte, Reife Grad and stress released heat treatment and wear resisting property of vanadium high grade cast iron, and found that these are superior to those of plain high grade cast iron. On the stress released heat treatment at 500～600℃, for 6 hours, vanadium cast iron keeps of better mechanical properties compared to those of plain cast iron. Vanadium cast iron is more resist to abnormal abrasion causion caused by increase of friction velocity

On Various Properties of Nodular Graphite Cast Steel

This paper describes at first the outline of the theory of high grade cast iron manufacturing that has been clarified by one of the authors through a fundamental study of the relation between cast iron and its oxygen contents. In place of the relation between the oxygen content of cast iron and its qualities, the relation between tensile strength in cast state and variation of structure was examined. A little difference in the degree of deoxidation of cast iron was indistinguishable by analysed oxygen content. To grade the qualities according to the variation of structure is the most accurate and simplest method. When nodular graphite hyper-eutectoid cast steel containing less than 1.7 per cent carbon is produced the theoretical foundation for determining carbon and silicon contents is to choose the reciprocal relation between the points on the line Eγ or in the lower areas under the line Eγ in the basic projection diagram of the Fe-C-Si system. According to this theory, an investigation of the various properties of nodular graphite hyper-eutectoid cast steel was carried out. The results obtained can be summarized as follows : (1) This cast steel does not call for so careful selection of materials, and is of higher value in mechanical properties than those of DCI, malleable iron and cast steel. (2) Since this metal has far better castability than cast steel and DCI, it is possible to manufacture castings of thin section and complicated shape. (3) Compared with gray cast iron and malleable cast iron, this cast steel is very useful for electric and magnetic material. (4) Wear resistivity of the pearlitic type of this metal is far superior to any of the ordinary cast iron, pearlitic cast iron and DCI. Wear resistivity of the ferrite type is the same as that of DCI, but it is far superior to the black heart malleable cast iron. (5) This cast steel is material that has excellent property for induction surface hardening, even in the case of ferrite type, and after heat.treatment it has the about 40～50 R_c in the surface hardness. The Jominy hardness curves of nodular graphite cast steel were measured. Compared with the pearlite type, cast steel of ferrite type has low quench-hardness bccause of its carbon concentration in austenite

Studies on the Wear Resisting Properties of the Spheroidal Graphite Cast Steel

The mechanical properties of the spheroidal graphite cast steel were already reported by the authors. This investigation has been made to compare the wear resisting properties of the spheroidal graphite cast steel with those of other cast irons. The surface hardness of the wear test pieces before and after the wear testing was measured. The results of this investigation can be summarized as follows : (1) In the dry abrasion between specimens of the same quality, the spheroidal cast steel is remarkably improved its wear resisting properties by oil quenching and tempering treatment. (2) In the dry abrasion and oil abrasion between specimens of the different qualities, in the pearlitic type, this cast steel is superior to the ductile cast iron. (3) In the case of dry abrasion, the difference between the surface hardness of the wear test pieces before and after wearing, became larger with an ordering of ferrite, pearlite, quenching and tempering matrix, and bainite. These differences have no relations to graphite shapes or wearing amounts

Some Investigations on the Cerium-treated Cast Iron

The effects of the addition of cerium on the macro- and microstructure of hypoeutectic and eutectic cast iron have been investigated and further, some experiments, were carried out to produce the high strength and rapid-malleable cast iron containing high silicon by the addition of cerium. The results obtained were as follows : (1) With the increase of the cerium content, the structure of cast iron changed from a grey iron to a white iron passing through an inverse chilled iron. When the composition of cast iron was fixed, the amount of cerium necessary to get white cast iron from a deoxidized melt was less than that from an oxidized melt. (2) It was verified that white cast ironization with the addition of cerium was not caused by its alloying such as in the case of manganese or chromium, in which they form special carbides, but by the supercooling of melt accompanied with strong deoxidation by cerium. (3) The mechanical properties of cerium-treated rapid malleable cast iron having the high silicon contents are higher than those of the commercial black heart malleable cast iron, and by controlling the amount of cerium, carbon and silicon in cast iron, the castings of a larger section than the maximum size which has been applied to ordinary malleable cast iron can be made

Study of Magnesium Treated Nodular Cast Iron by Reducing in the Electric-Arc Furnace

Magnesium treated nodular cast iron (D. C. I.) was investigated by the reducing refining in the acid and the basic electric-arc furnace. By the reducing refining in arc furnace the oxygen and sulfur contents in molten metal were decreased, and so magnesium amounts necessary for the ductilization of graphite decreased. This reducing degree of magnesium amounts were examined. Further, the shrinkage cavities in the basic and the acid furnace were compared

Study On Wear Resisting Properties of Deoxidized High Grade Cast Iron. I : On Wear of Flake Graphite Cast Iron

Comparison was made between wear resisting properties of deoxidized high grade cast iron and those of other cast irons, and the following results were obtained : Deoxidized high grade cast irons have superior properties in wear resistivity by its strong, tough qualities, and graphite carbon. The reason is that the pearlitic matrix has strong and tough qualities, wormy flake graphite or spheroidal graphite being created by the deoxidation. Eutectic graphite cast iron does not prove wear resistivity under heavy load

A Rare Case of a Symptomatic Tumor Found in the Groin Area : An Atypical Location Unexposed to the Known Causes

Nevoid basal cell carcinoma syndrome (NBCCS), also known as Gorlin syndrome, is a rare hereditary condition characterized by a wide range of developmental abnormalities and a predisposition to neoplasms. The syndrome consists of early-onset and/or multiple BCC. Herein we report a rare NBCCS case in which the first BCC onset occurred in the groin area. To the best of our knowledge, there have been no reports of first-onset BCC in the groin area in an NBCCS patient of any race