This paper is the continuation of and the supplement to the previous report on the measurement, with the method of magnetostrictive vibration, of Young’s modulus and ΔE-effect in annealed nickel-cobalt alloys covering the whole composition range.

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Following the previous report, the experiments were carried out on Fe-Si and Fe-Co alloys concerning the following items: 1) the concentration of Cu^••, H^• and Cl′, 2) the change of HCl (37%) quantity, 3) the replica limit and 4) the relation between optimum replica solution and corrosive reduction by HCl. The samples used are shown on the Table 1 and the results of experiments are shown on the Table 2 and Table 3. On the chemical plating, some relations are found between the ions of H^• and Cl′ in the replica solution varied according to the concentration of Si and Co in the alloy. Substituting the concentration of H^• and Cl′ by HCl quantity, these relations are shown on Fig. 1 and Fig. 2.
In the figures, the newly gaind HCl curve is symmetrical with the curve of corrosive reduction against the straight line, which connects the two point of intersection of the HCl curve and the corrosive reduction curve, when gradient of its line is kept constant.
The right-side point of intersection of the both curve represents the replica limit point. Then, the action of H^• and Cl′ in the replica solution is shown quite same with the previous report.

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In this report, the experiments were carried out on Fe-C, Fe-C-Ni, Fe-C-Cr and Ee-C-Ni Cr alloys concerning the following items: 1) the change of HCl (37%) quantity on the 3%Cu (NH₄)₂Cl₄·2H₂O solution, 2) the relation between optimum replica solution and corrosive reduction by HCl, 3) the concentration of Cu^••, H^• and Cl′ and 4) the compositions of replica solution in the Fe-C-Ni, Fe-C-Cr and Fe-C-Ni-Cr alloys.
The samples used are shown on the Table 1 and the results of experiments are shown on the Table 2 and Table 3. On the chemical plating, some relations are found between the ions of Cu^••, H^• and Cl′ in the replica solution varied according to the concentrations of C in the iron. Substituting the concentration of H^• and Cl′ by HCl quantity, these relations are shown on Fig. 1 and Fig. 2. In these figures, the newly gaind HCl curve is symmetrical with the corrosive reduction curve against the straight line which connects the two points of intersection of the HCl curve and the corrosive reduction curve, when the gradient of its line is kept 4/3. The replica solutions which contain HCl quantity at the range of 1.60∼0.00 cc are capable of being replaced by many Fe-C alloys.
Next, HCl quantities in the replica solution for Fe-C-Ni,Fe-C-Cr and Fe-C-Ni-Cr alloys are shown by the mean value of HCl quantities which are used in the case of replica of every Fe-C,Fe-Ni and Fe-Cr alloys.

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The Orientations of single crystals of Al-Cu alloy were determined by Laue and Stereographic projection method. The distortion caused by tension for these specimens were studied. The relation between N′ (the numbers of slip bands per unit length on the normal to the slip plane in No./mm) and S (the resistance on the slip plane to the direction of slip in kg/sq mm) in single crystals of Al had already been reported by K. Yamaguchi that N′ was proportional to S. In single crystals of Al-Cu Alloy this rule holds good in the later stage of distortion. The orientations of crystals are defined by the angle θ (between the axis of specimen and the normal to the slip plane) and \varphi (between the direction of slip and the projection of the specimen on the slip plane.)
As to the relation between θ and Sc (critical shearing stress) Sc is minimum when θ=45°, and it is inclined to increase with the deviation from 45°.
Accordingly, the relation between S and s (shearing strain) depends on the orientation of crystals.

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Abnormal hardening during cold rolling of Cu solid solution. In the 4th report, the abnormal hardening during cold rolling of Al α solid solutions was reported. In this paper, the same experiments were carried out on some Cu α solid solutions, and the same results were obtained. Other α solid solutions may also be the same in result. Why? That is the very interesting problem, and the reason can easily be assumed. In the next stage, many physical properties of such cold rolled solid solutions must be determined, and then the internal movement may be cleared up.

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Metal cast in sand mould flows through a runner and sprues to fill the vacancy of casting. In the present paper weight of metal passing each sprue was measured separately and the metal flow in sprues was discussed. If the metal is assumed to flow through a runner in one direction from the gate, larger part of metal will flow to the sprues nearer to the gate. But,in general, larger part of metal flows to the end of the runner and then goes back and enters into the sprues nearer to the end of the runner. So the proper size and angle of the sprues make the metal flow steady.
The metal flow in a vertical ring was also investigated. When the metal enters tangentially into the bottom of the vertical ring, it fills the ring steadily if r is over 1.5, assuming r to be the ratio of the rectangular sectional area of the ring to that of the sprue. And when the metal enters with an angle of 45° into the ring, it fills the ring steadily if r is over 0.5.

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Concerning the stress in various alloys,a number of interesting papers have hitherto been published. However those are of the homogeneous, and no report has been made on such heterogeneous specimen as double body steel inserted by baking with sintered body. The procedure utilizing the Heyn’s method in the determination of residual stress in double body round bar in this investigation was as follows : The round bar specimens were made by inserting the sintered iron bar made of 0.35% and 1.0% carbon steel in external solid tubed steel by baking. The solid tubes were usually about 60 mm, long and 12 mm, in diameter. The inner circumferential surfaces were machined and ground to a finish, which permitted measurement to ±0.01 mm. The sintered body were made of iron powder which had been cut from the same steel to solid cylinder and stamped. Results obtained are as follows: The magnitude and distribution of residual stresses in double body bar specimen combined with sintered iron body quenched from 950° into ice water have been deducted to compared with single cast body, and the rate of deduction increases as the volume ratio of the sintered vs. the solid increases, and by a suitable procedure,the specimen which retains no stress in the surface and have high hardness by quenching can be obtained.

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The present investigation was carried out to ascertain the effect of nitrogen on the elongation at yield-point and the serrated deformation in steel.
Tensile tests were carried out with irons, low carbon steels and low manganese steels containing various amounts of nitrogen, at the temperatures from 0° to 320°.
All the specimens were air cooled from 950°, and then slowly cooled after tempered for 3 hours at 550°C.
From the present investigation authors concluded as follows:
(1) There is a clear correlation between the nitrogen in steel and the elongation at yield-point or the serrated-deformation.
(2) In pure iron the serrated-deformation increased severely with the increase of nitrogen up to 0.007 percent,over which the slow increasing may be seen.
(3) With the increase of the rate of deformation,the degree of serrated-deformation apparently decreased and the elongation at yield-piont increased a little.
(4) The range of severe increasing of the serrated-deformation and the elongation at yield-point are reduced by carbon.
(5) By the addition of denitrogenizer on low manganese steel the serrated-deformation and the elongation at yield-point diminished or almost disappeared.

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In this report, the relation between graphitization and decarburization of white cast iron in the process of annealing of white heart malleable cast iron was studied. When free cementite in cast iron was diminished by decarburization, it changed to austenite or ferrite. When granule rtemper carbon was decarburized,however,sufficient carbon would diffuse to matrix at first. After some time this diffusion of carbon weakened because some gap broke out between temper carbon and matrix. Such a granular carbon declined by decarburization can not become a source of carbon on decarburization or a collecting nucleus of carbon on graphitization.
Many experimental results which occurred on annealing of white heart malleable cast iron can be explained by the fact mentioned above.
The effect of some elements contained in it such as C, Si, Mn,P, S, Ni and Cr on carbon concentration of decarburized zone was studied in comparison with the effect on graphitization, but could not find a definite connection between those phenomena.

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For the purpose of improving the magnetic shunt alloys hitherto used, the magnetic properties of Fe-Ni-Cr alloys,containing 30-60% of Ni,1-18% of Cr and having no allotropic transformation,were measured at various temperatures ranging from −50° to 100°.It has been found that those alloys with the magnetic transformation point of about 100° show excellent characteristics of magnetic shunt as follows: The permeabilities in 400 Oe at 0° are 5∼20 and their temperature coefficients, 0.003∼0.040,the permeability varing almost lineally with the temperature.And the authors have named them “M.S.(initials in capital letters of magnetic shunt) Alloy”.

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This experiment was performed for the purpose of determining the diagram of Hg-In binary alloys and finding if they would solidify below −60°C at which the Tl-Hg alloy including Tl 8% melts. The ternary system of Hg-Tl-In was also investigated. As the results of thermal analysis using copper-constantan thermocouple which jointed four pairs in series, three compounds In Hg₅ (m. p. −17°C), InHg (−23°) and In₁₁Hg (decomp. at 94°), two eutectic points at In 23% (m.p. −37.5°) and In 50% (m.p. −32.5°) were found as is shown in Fig. 1. Both eutectic alloys did not melt below−60°. The ternary system of Hg-Tl-In did not possess melting point below −60°, but two ternary eutectics are found at the point of 73%Hg,10%Tl,17%In and 51%Hg,8%Tl,41%In at −55° and −41° respectively. (Fig. 4)

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Although silver alloys have favourable properties for casting, soldering and other dental techniques,their fatal defect is the tarnishing by the oral liquid.
In this report, the effect of compositions as well as the surface-treatment of the silver-aluminum alloys chiefly on the tarnish-resistance against natrium sulphide solution, has been studied.
Although their tarnish-resistance against sulphur is not complete, the best result is obtained with the alloy containing about 6% of aluminum and 0.2% of antimony and silicon, respectively. The tarnish-resistance of the alloys containing 6 to 8% of aluminum is found to be improved by tempering at about 390°C, due to the formation of Ag₃Al-phase. While the improvement of the tarnish-resistance of the alloys by heating in the air of ordinary or diminished pressure is found to be small, the alumina-film produced with the anodic oxidation showed the best tarnish-resistance against sulphur.

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The authors studied the distribution and the value of casting stresses in a bell by cutting it in round slices.The stresses showed the maximum value in the vicinity of the change of the thickness in it and these stresses may be considered as contributing to the sound. In spite of the fact that the sound was generally improved in proportion to the increase of tin content, an excessive content of tin retarded resistance to a blow by a wooden bell hammer. The authors pointed out that the content of tin in bells must be in the range of 11% to 13%. On the other hand, various defects in Komano-tume (the lower part of bells) had bad effects on the sound,and must be rectified as for as possible by using a moderate method. A marked segregation in bells was almost due to the construction of mould and the suitable cooling velocity for segregation.

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By studying the NaOH tin-plating solution and the sodium phosphate tin-plating solution,the following conclusions were obtained:
1. The best composition and condition of the plating in the NaOH tin-plating solution are the following:
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But this solution is unsuitable for thick plating.
2. The best composition and condition of the plating in the sodium pyrophosphate solution are the following:
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3. The NaOH solution is unsuitable for thick plating or for room temperature plating. The sodium pyrophosphate solution is suitable for thick plating.(It is possible to plate for 20 hours continuously.) It is also possible to plate at room temperature.

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