Some years age, the author discovered that iron-silicon-nickel alloys comtaining about 8_??_12% Silicon, about 14_??_18% nickel and balance iron show peruninvar characteristics, and applied the name “Senperm” to them. As the magnetic characteristics of Senperm are improved by various heat treatments, we can expect the growth of superlattice in Senperm region as in Permalloy region. Therefore the measurement of electric res resistance at high temperatures, the dependence of electric resistance (p), saturation induction (4πI_∝), and seturation magnetostriction (λ_{_??_∝}) on heat treatment or on the concentration, and X-ray analysis were carried out.
The experimental results show that the magnetic characteristics of these alloys are similar to that of Permalloy and that there would be order-disorder transformation in these regions near 350_??_370°.

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The temperature of the quenching specimen is recorded on photographic paper by means of the oscillograph placed in the circuit of a thermo-couple inserted into the specimen. The results are given for the quenching ability of water, soybean oil and air at various temperature.
From the results, water is superior in quenching ability to other kinds of media such as soybean oil and air. The quenching ability of water is more than four times that of soybean oil and forty times more than air.

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The object of this study is to obtain the best magnetic anisotropy of cold-rolled silicon steel by annealing at comparatively low temperatures say about 800° Experiments were made on the cold-rolling and recrystallization textures, and the relation between the cold-rolling texture and (110) [001] orientation were considered from a crystallographic point of view. From these experiments, which are now being continued, it has become clear that rotation twins and “Sammelkristallisation” phenomena art important.

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(i) When we introduce the idea of sliding resistance and resistance to rupture and use the hypothese of the greatest shearing stress as in the 1st report, we can apply. Woodvine's theory for the bending properties in the (two surface) case of hardened steel. But in this case we must take care of the case break point, which often appears after some plastic d eformation.
(ii) Case hardened steel is not especially rich in velocity sensibility for its charpy value is almost equal to the energy of rupture by statical bending test.
(iii) The case hardened layer on the surface of the greatest bending load is most resistant for sliding.
(iv) In the specimens of (_??_=Const), the impact value per unit area of the high height specimens are superior to those of low height.
(v) We can apply the two layer theory by Woodvine in the all surface case hardened steels.
(vi) In the notched specimen, there is a stress concentration around the notch part. Thus, the case depth which brings on the rupture of separation type moves to the shallow depth.
(vii) This tendency to the rupture of separation type moves to the bigger notch in the lower temperature.
(viii) With the increase of impact velocity, the notch sensitivity does not increase in the case of hardened steel.
(ix) In the high height specimen with the standard notch, its impact energy (E/bh²) is abosrbed much more than that of the lower height specimen.

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In this report, first, I discussed the various methods of case depth measurement by the diffusion theory and showed the experimental results thereby obtained.
a) The measurement by the slow cooled specimen after carburization favors the study of carburization mechanism and comparison of carburization technic. It consists of two methods, one is the reading of carbon difference from matrix carbon conc, the other is the reading of the decided carbon conc. They show definite differences. The reading method of the decided carbon concentration is best for comparison of the with reading of the, hardened case depth.
b) To do the measurement by the hardened (and tempered) specimen after carburization, speciemens of the same dimension should be used pant. This method ascertains its hardness distribution and structure of the used part.
c) We can apply 3 equations of carburization in the carburization of various carburizing steel, such as C steel Cr steel and Ni-Cr steel with 0.2%C and the dimensions of ordinary parts as,
_??_
where e _??_, C=weight concentration, D=diffusion const. T=temp., t=time, S=area, p=density of steel, W=weight increase per unit time, W=weight increase. C₁=const.
d) Chrom steel absorbs carbon sooner than garbon steel, but saturates sooner and at higher temperature its tendency becomes inferior to ordinary. temperature.

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Tinrich binary alloys, as Sn-Ag, Sn-As, Sn-Fe, Sn-Hg, Sn-Mg, Sn-Mn, Sn-Ni, Su-P, Sn-S, Sn-Se and Sn-Si, were prepared and their corrodibilities in HCl, H₂SO₄ and HNO₃ solutions were tested. The results obtained are shown in Tables 1 to 5. Experiments on anodic behavior of Sn-Bi alloys in NaCl solution were also undertaken.

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The research was carried out to utilize the aqueous solution and precipitation of hydrophosphate (containing Zn, Mn and Fe), which decreased the activity of film-formation. And it was found that the precipitation contaning phosphate is possible to be used again asrust preventitative by the addition of a hot solution of 2_??_3 percent of oxalic acid in finely powdered state. The film thus formed is applied as a basis for a coating of paint or other materials.

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