The steel made from sponge iron and loop (Luppe) is generally thought superior to that from steel scraps, because of the former's virgin or fresh quality. However, even such steel wiht virginity, may loose the fresh quality when re-melted.
Steel manufacturers are used to add some necessary alloying elements to the base iron, which has not contained any additional elements, in order to obtain the expected result, while they cannot refine such materials as steel scraps as they are which contain the ordinary steel components alone and consequently reveal no chemical reaction.
It is suggested that the superiority of sponge iron is, in reality, due to the absence of any other steel mixtures, and not due to the virginlty. It is necessary to follow a "dynamic" methol in refining the sponge iron with a considerable amount of carbon. The good result would not be obtained by following the ordinary method of refining, even in case where only a little quantity of carbon is present When steel scraps are used as the original material, the existing components other than iron should be removed first by means of oreing and then necessary elemehts may be added.

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It was intended that metallic materials equivalent or superior to the 110-kg nickel-chromium steels would be made from elements of the domestic resource. The elements Cr, Mn and Mo were thought most efficient among elements of the domestic resource, in so far as the mechanical properties and the mass offect in quenching were concerned. From this viewpoint, chromium-manganese or chromium-manganese-molybdenum steels were prefered and studied, which were found having Properties equivalent or superior to the 110-kg nickel-chromium steels.These steels, containing approximately 0.05% C, 1.0-2.5%, Mn, 7.0-9.0% Cr, and balance Fe (or 0.05% C, 1.0-2.5% Mn, 5.0-7.0% Cr, 0.3-0.5% Mo and balance Fe), were recommended for applieations Where heretofore the 110-kg nickel-chromium steels had been used as struetural parts.

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Bakelised roll neck bearings manufactured by the Yawata Steel Works are called NITTELITE roll neck bearing and of a special synthetic composition. They are used in several rolling mills at Yawata Steel Works, showing such excellent results, as follows.
(1) On a cold roll for tin plate in which the whole series of stands had been fitted with NITTELITE bearings, the saving of power was 79%.
(2) On an 18tn. continuous rolling mill, the power saving was 27%, and the life of the bearings, when compared with that of the Babbit, increased from 10, 000t to 60, 000t
(3) On a wire rod mill the installation of NITTELITE bearings increased the bearing life to 1·6times and the power saving was 13%.
Further, other advantages, the methods for lubrication and the setting up of NIITELITE bearings are described in the present article.

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Effects of the addition of Ni, Fe, Mn, Zn, Cd, Co, Cr, Sb, Ti and W on the mechanial and chemical properties of two-phase aluminium-bronzes was examined. It was confirmed that nickel is not necessarily indispensable element to improve the properties of the two-phase aluminium-bronze, since the presence of nickel in excess of 2% raised the proof stress and hardness, but decreased the ductility remarkably and imparted an almost negligible effect on the corrosion-resistance. As the reslt of the study on Cu-Al-Fe-Mn series alloys, a new alloy "HB-5" was developed, the Properties of which are as follows:
(1) Chemical composition: Al 10·5; Fe 4; Mn 4; Zn 1 max.; Cr 0·5% max.; Cu balance.
(2) Physical properties: Specific gravity 7·28; coefficient of thermal expansion (20-200°C.) 1·91×10-5; Young's modulus 11, 360kg/mm²; electrical conductivity(Cu 100%)5·5%.
(3) Mechanical properties:
Effects of quenching and tempering treatment on the hardness, Charpy Impact value, tensile. properties, microstructure and X-ray intereference ring of extruded aluminum bronze rods (Al 10·5% and 11·7%) were also examined. It was concluded that the hardening or softening of the two-phase aluminum-bronze is due to the sepatation of α from β, or to the decomposition of β into α+δ, or to combination of both changes. It should be noted, however, that the mechanical properties of these alloys with approximately eutectoid composition varies to a considerable extent with a minor variation in the aluminum content, rate of cooling, the mass of specimen, etc. The difficulties encuntered, with the commercial heat treatment of these alloys are presumably due to the abovementioned evidences.

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