The effect of nickel, manganese, chromium, molybdenum, tungsten, titanium, vanadium, cobalt and silicon, each alloyirg up to 2%, on the austenitic grain size and its growth of 0.8%, C steel were studied by carburization method, heating at 850°, 925° and 1000° for 1, 2, 3, 4, 6 and 8 hours respeictively.
Manganese and cobalt increase the austenitic grain size and promote its growth by heating. Silicon has a small effect on the grain size and its growth in less content than 1.5%. Nickel, chromium, molybdenum and tungsten refine the brain size and the addition of these elements raise the coarsening temperature. The addition of vanadium or titanium is very effective; steels alloyed more than 0.3% of one of these two elements show very fine grain size, No. 9, and any grain growth is not observable even on heat at 1000° for 8 hours.

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Young's modulus of elasticity of iron single crystals has been measured at room temperature by the method of magnetostrictive oscillation, and the elastic constants have been determined by the combination of the data obtained from the above measurement apd the measured value of volume compressibility of polycrystalline iron. The results are in good accordance with those hitherto obtained.

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The crystal-structure of Co electrodeposited from cobalt sulpLate solution have been investigated by means of X-rays. The conditions of electrolysis are as follows: The current density varies from 0.01 to 0.1 A/cm², and tl, e PH of the solution from 1.2 to 7 and the temperatute of the bath keeps always the constant temperature 30°. The results of the author's investigation areas follows: (1) At low current densities with high Pa the electro-deposits are almost of the hexagonal close-packed lattice. (2) In all other cases the deposits are always of the mixture of the hexagonal close-packed and the face-centered cubic lattices. But it is observed that, in general, the former modification tends to become stronger at higher values of PH than at lower ones, whilst the latter modification shows an opposite tendency. The case of PH=2 is an exceptional one. The anomaly of the behaviour of the α(10 1) line is also observed.

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Der Gleichgewichtszustard sowie das Seigerungsverhalten des Al-Sn Systems n urde mittelst thermischer Analyse, mikroskopischer Methode and der von einem der Verfasser corgeschlagenen Zentrifugalmetallurgie untersucht.
Das von M. Hansen angegebene Zustandsdiagramm wurde im wesentlichen bestätigt and der eutektische Punkt wurde bei 225°±3°, 0.53% Al bestimmt.

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Many kinds of high speed steels are commonly used to day, but their compositions belong mainly to a type, so called 18-4-1, type which contains 18% W, 4% Cr and 1% V, and also to some high grade high speed steels with 2_??_18% Co. In the present investigation the ordinary 18-4-1 type steel and that cdntaining 5% Co are used as specimens; they have been prepared in Tan.mann resistance furnace from iron with low percent of C manufactured from high grade iron sand produced in Izumo provins, and ferroalloys of Cr, W, V and Mo. We have measured the hardness and the cutting durability, and observed the microstructure of these specimens, applying different heat-treatments. And the effects of the various elements, such as C, Cr, W, V and Mo, on above mentioned two kinds of high speed steels are studied, From the results of these investigations, we can produce a new kind of high speed steel superior that of the conventional high tungsten high speed steels.

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To eliminate nickel from the heat-resisting light alloys, the author has carried out some experiments with alloys of aluminium not containing nickel. Among these alloys, he select the alloy in a series of supper duralumin, or Y alloy in which manganese is substituted for nickel. The alloy has the following nominal composition.
Cu 4.0%. Mg 1.0%. Mn 1.0%. Al remainder. The experiments have been carried out not only on the physical and mechanical properties, but on the practical use of the alloy as a part of the aero-engine.
These results are fairly good, and therefore the alloy is recognized as the substitute alloy for Y alloy, which can be used for the casting alloy of aero-engine parts.

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