The experiments are made for a soft mild steel rod (S 25C) and a steel plate (SPC-1) under the constant blasting condition, viz. blasting pressure, 3 kg/cm₂ (the bead speed measured at the middle point on the nozzle centerline about 100 m/s) : blasting distance, 100 mm : weightmixing ratio of water with glass beads, 1/1.8 (glass beads of 158 μ in mean shot diameter). The fatigue strength under the rotatory bending and the residual stress calculated from the variation of camber on the etching are inspected.
Comparing the experimental data with those of the usual shot peening, main results obtained are as follows :
1) The endurance limit ratio is greater than or equal to that in shot peening, and the influence of “over peening” is very little.
2) The residual stress zone is decreased by about one-fifth, and the maximum value of residual stress exists in a nearer part to the blasted surface. These results mean that the fatigue strength becomes to be high.
3) The obtained surface is smooth and grossy satin or matte.

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In conventional surface grinding, the size and form errors greater than several μm are unavoidable, because of the stick-slip motion at the slide of wheel-heads, the elastic and thermal deformations of machine tools, workpieces and chucks, the fluctuation of lubricant film thickness on table slideways, the variation of the wheel and table speeds, the wear of grinding wheels and so forth.
The paper describes some experiments with a surface grinding machine equipped with a special attachment, which is composed of a cantilever, a weight and a hydraulic servo mechanism and causes the machine tool structures to deform slightly in response to a command and corrects the errors due to the above-mentioned sources. The machining errors have decreased to 0.3 μm in the size decrease error from a reference surface and to 1 μm/60 mm in the longitudinal form error by using the attachment.

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In order to clarify the mechanism of crater wear of carbide cutting tools in the region of low cutting speed which accompanies the built-up edge, the states of wear particles are analyzed using electron probe micro analyzer.
The findings are; (1) the cause of crater wear is attributed to the falling down of the built-up edge and the “belag”, (2) the mechanism of this type of wear is identical to the “tear by sticking matter” which is found and named in the first report.
Further, the method for rapid tool life testing is contrived in the speed range mentioned above, and this method exhibits good approximation.

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By making huge chips of a-brass using a material testing machine, anisotropy in metal cutting process is investigated.
The results of experiments are summalized as follow :
1. The theory of anisotropy due to R. Hill is verified to be in good conformity with the experimental results.
2. Relative direction of the anisotropy axis, which is in the plane of flow, to the direction of maximum shear strain rate varies from -45° to 45° during chip forming process, while the directions of maximum shear strain rate and maximum shear stress are almost in coincidence during the process. The angle η' between the both directions varies ±1 degree at most.
3. In spite of produced anisotropy, research works presented hitherto based upon the so-called shear plane model appear to be still appropriate because of η'=0 unless the shear stress on the shear plane is discussed. However, any stress analysis with isotropic theory will be not fruitful due to the large anisotropy.
4. The cutting model proposed by M.C. Shaw may be explained by the effect of anisotropy. However, it will be not much useful due to the small value of η'.

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In this investigation, surface grinding experiment has been carried out to evaluate the influence due to jet pressure of grinding fluids on grindability such as residual stress and changed structure in grinding layer, and excess cut, that is concave shape, at the central portion of ground surface is observed. And the residual stress and concave shape are investigated in relation to the grinding temperature, most influential dominating factor of this. A summary of the results are shown below.
(1) As the jet pressure of grinding fluids changes from 0 kg/cm²to 6 kg/cm², residual stress, the amount of excess cut and grinding temperature are shown about constant value.
(2) As the jet pressure of grinding fluid (the fluids containing sulfurized oil and spermwhale oil) changes from 0 kg/cm² to 18 kg/cm², reduction of changing value of residual stress in grinding layer is shown about 50-80%, and then the amount of excess cut could hardly be observed.
(3) It can be seen that change of the grinding temperature, residual stress on grinding surface and the amount of excess cut are in good corresponding relation with the change of jet pressure of grinding fluid.
(4) As the jet pressure of grinding fluid changes from 0 kg/cm² to 18 kg/cm², reduction of hardness and depth of the hardness distribution in hardened layer are shown about 20-40 %.

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Thermal deformations of machine tool column in steady-state are studied in this paper, as a part of the study on the thermal deformation of machine : tools.
Temperature distributions and thermal deformations of cast iron column and plastic model column are measured in stead-state condition when the internal heat sources are given. Then the temperature distribution and thermal deformations of column are analyzed by the finite element method.
From this study the following results are obtained. When the column wall is heated by a point heat source, highly warmed zone is limited in the small area around the heat source, and thermal deformations are performed by these small area. As the results, at the upper wall from the heat source thermal displacements are proportional to the distance from the heat source, and bellow the heat source thermal displacements are extremly small.

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This paper presents a general method for analyzing and designing cam mechanism which has a one-degree-of-freedom follower system. To improve the dynamic characteristics of the positioning system composed of cam mechanisms, the residual vibration amplitude must not change widely by the fluctuation of cam rise time. Dynamically ideal cam can be obtained by determining the contour to have a desired characteristics curve, which show the relation between vibration amplitude and cam rise' time. Herein the design method of cam contour is described by which the residual vibration are reduced to desired small amplitudes at plural arbitrarily chosen rise times taking into account of viscous damping. By this method a stable cam at high speed can be obtained. Then the cam profile which extinguishes the vibrations at N arbitrarily chosen rise times is determined by (2N+5) power polynomials.
Moreover a method to extinguish the vibrations at plural arbitrarily chosen rise times, even if the follower is viscous damped, is described. These theoretical results are verified by some experiments.

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In this paper, using the probability expression (p.d.f.) on the 3-dimensional characteristics of the solid surface as we explain in the lst report, the general expressions standing for the basic quantities on the state of affairs of all contact phenomena for all contact condition, for example the number of contact spots and the real contact area, are obtained according to the probability theory.
And moreover the more detailed expressions are developed from the above expressions for the γz^ν type distribution concerned withe the roughness amplitude z as one of the typical distributions of all solid surface roughness.
It is pointed out that the analysis for the mechanism of the contact phenomena is possible according to the typical relationship, which is obtained by our method, between the deformable coefficient and the approach, and then its evaluation method is concretely demonstrated.
The method determining the factors, still more, concerned with the 3-dimensional characteristics, the geometrical parameter, of the solid surface, which is needed in case of the analysis for the quantities of the state of the contact phenomena, is releated.

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