Seizing between shofts and bearings is an incidental occurence, so it is difficult to make clear the phenomenon, but it is well-known that its mechanism consists of two processes, birth of the seizing-mucleus and its growth. Therefore, there is no seizure where theie is no seizing-nucleus to come out and even if it does come out it does'nt motter if there is no growth of nucleus.
To make clear the property of seizing, we must study the way of rise of seizing-nucleus and the process of growth of the nucleus. It is the object of the 1st report to make research on how grows the sezing-nucleus on bearing metals.
First, to find out the growing mark of a sezing-nucleus on bearing metals from replica caused by roughness of shaft surface on it, the order of replica by shaft's roughness is innestigated. Then it is found that replica is affected not by load but by its roughness, and that the roughness replicated is less than about H_max=0.5μ.
From the results exprimented on seizing up, it was made clear that there are three typical growing of the nucleus, Slender, Flat and Similer and that among which Slender type is the most suitable one for bearing metals.

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Seizing-up between a shaft and its bearing is caused incidentaly, so it is difficult to make clear the seizing phenomenon. But it well-known that the mechanism consists of two process, being born of seizing-nucleus and it growth.
On the 1st report, I investigated on the procees of growth of the seizing-nucleus on the shaft surface. In this report, I studied the generating incentive of seizing-nucleus with statistical method, because seizing is an accidental-phenomenon as describes before.
Useing an equipment of cross cylinder type, the expreiment was carried out to measure the runing time for seizing up a shaft under several conditions, and to make the histgrams of those times for analysing as statistical-phenomenon.
The results are as follows:
(1) The histgrams are distributed logarithmiconormaly, and the standard deviations of them are proportional to the means of runing time to seizing-up.
(2) The movements to generate seizing-nucleus relate to the products of preventing resistance being on the sliding surface and runing time wihout seizing-up.
(3) The results of (1) and (2) may lead to the theorization of runing-in.
(4) The load and the roughness of shaft suraface act inverse-proportionally upon the movements of generating seizing-nucleus.
(5) The oil film has a large effect upon the results, and it is difficult to maintain it at the same condition, so no-good to infrence seizing-up after smol times of the experiments.

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We reported formerly on a comparison of Hevea, Neoprene GN-A, Hycar-OR-25 and Silicone-T.S. under the same title. In that study, we found merits and demerits of these rubbers and those which have some special merits always possess some great demerits. In designing rubber vibration isolators, it is eagerly desired to make such rubber which would have the merits soley made up from those other kinds of rubbers. In workshops some blended rubbers and coated ones are produced for the purpose of making some improvements on properties. So we prepared some specimens which were blended with two or three of Hevea, Neoprene and Hycar, and some others were coated by Neoprene or Hycar with the thickness of 1mm on the free surface of Hevea stocks. Then we compared such specimens with single rubbers which were reported in the 1st. report by the resonant method. And we observed their dynamical charcteristics, amplitude dependency, oil resistancy along with some other data.
(1) Dynamical characteristics of blended rubber....spring constant k and damping coefficient c were calculated, their variations in relation to temperature have same tendencies with single rubbers. And their values of spring constant decreased and damping coefficient generally increased. So loss factors L became large, which is considered as a bad tendency.
(2) Amplitude dependency of the blended rubber....This tendency of blended rubber is more remarkable than in single one. The position of the peak of the curve in relation to stress amplitude and characteristic function φ(s) moves to the larger side of stress amplitude.
(3) Oil resistancy....After immersing rubbers in machine oil for more than 60 days, we measured the considerable decrement of spring constant and internal friction and found that the oil resistancy of blended rubber was less than that of each component of single rubber. But when Hevea was coated by Neoprene or Hycar, though its oil resistancy was some-what less than that of single Neoprene or Hycar, they fulfiled their requirements very well as the oil-proof material for the Hevea.
These three characteristics chiefly are caused by the structure of blended rubber molecules.

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We observed the failures of five different kinds of cemented carbide tools with grades S1, S3, TX2, TX3, and G1 at cutting plain carbon steel, showing the predominant tool failures for the grades and cutting condition used applying the fundamental classification of the tool failures appearing at the cutting of steels.
In this experiment, we carried out the intermittent cutting test besides the usual continuous cutting. Here, we noticed that the high feed in usual continuous cutting accelerats the occurrance of the crater because of its high temperature and pressure on the top face of tool, while the intermittent cutting accelerats the rise of chipping by its severe impact.
The occurrence of cratering and chipping are the most fundamental causes of tool failures, the grade possessing the properties resisting against these occurrence to the maximum extent being the most favourable for machining practice. In this experiment, we could not find such a grade. This fact shows that the resisting properties of the carbide grade against chipping and cratering are essentially contrary each other, that is, the superior grade in one property is inferior in the other. However, we recognized that it was possible to estimate simply these important properties on applying high feed in normal and intermittent cutting under the moderate cutting condition, respectively.
From the test results, we knew that the grade S1 containing much amount of TiC was best for its highly resisting property against cratering and flank wear, although inferior against chipping. On the contrary, the grade TX3 containing TaC was superior against chipping, although inferior against cratering. Namely, each grade S1 and TX3 has its reasonable applicability for machining practice.
On the other hand, the grade S3 and G1 don't stand for use because of their poor resisting properties against both chipping and cratering, as far as plain carbon steel concerns.

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Creep rupture properties have been invertigated on the vacuum annealed forged bar of commercially pure titanium KS-70. They were prepared by a consumable electrode double melting method within the temperature range from 200 to 800°F (93 to 427°C). (have been investigated.) The results are summerized as follows: (1) In the temperature range from 400 to 600°F (204 to 316°C) the temperature graph of creep rupture strength is indicated by an extremely gentle slope, compared with that of short time tensile strength. (2) The causes of this indication are possibly considered to be the strain hardening, the precipitation hardening influenced by foreign matters of extremely small amount in test material and so on, but they must under go a further study so as to be made decidedly clear. (3) However, it is confirmed by the investigation on hardness and by the analysis that hardening phenomena by oxidation did not occur on the occasion.

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