When one of the two block gauges adhering to each other is firmly fixed, the force required to slide the other in the direction parallel to its surface in contact with one surface of the fixed block gauge is considered to have a bearing on the wringing force of the block gauge. This force is called the tangential resisting force. Studies and reports have been made on this force, but without a theoretical analysis on it, they have failed to clarify the cause for its generation. This report presents a theoretical analysis on the tangential force and clarifies its characteristics through an experiment. The conclusion reached in this report is as follows:
1) The tangential resisting force must be studied as divided into two forces, dynamic and static ones.
2) The static tangential resisting force is proportionate to the cohesive force as described in Report 1. The coefficient of cohesion corresponding to the proportional constant is 0.150.20.
3) The dynamic tangential resisting force having a bearing on the coefficient of viscosity requires correction. The relation between the coefficient of correction and the coefficient of viscosity is expressed as α=3η+ 16.6.

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This paper describes the effects of the artificially controlled shear angle on the metal cutting process. From the experiments in which commercially pure lead is cut with various controlled shear angles, constant cutting speed, and depth, and various rake angles, the following results were obtained.
(1) Taking rake angle (α) as parameter and increasing the controlled shear angle (φ), the points (φ, β-α) move along a right convex curve on the φ vs β-α plane on which critical points giving a minimum value of cutting force (F_c, min), lie in the vicinity of Merchant's Line.
(2) The variation of φ does not influence the friction force on the rake face (CF), and the angle which gives a minimum cutting force (F_c min) gives a maximum value of coefficient of friction on the rake face.
(3) Hydrostatic pressure on the shear plane increases with the increase of φ, and does not influence the shear stress on it.
(4) It has been confirmed either the shear plane model does not agree with the cutting mechanics for low cutting speed or the angle φ is such that the total cutting power is not minimum.

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In this paper, with relation to the theoretical analyses on grinding mechanism which were described in the previous reports, following experiments are performed:
(1) Measurement of the tip angle and the distribution density of cutting edges. Special mention is made to the difference between results of surface roughness method and replica method in measuring the distribution density of grain tips.
(2) Measurements of the cutting pulses by grain tips in grinding. Successive cutting edge space is also discussed under the assumption that conical grain tips distribute three-dimentionally at random in grinding wheel. The experimental results agree approximately with the theoretical in consideration of difficulties of measuring cutting pulses when the magnitude or the spacing of cutting pulses is very small.

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This paper deals with one of the series of investigations about the mechanism of friction and lubrication in metal deforming processes. In the previous paper, the lubrication system that was presented, described a method by which the characteristics could be estimated by means of the microphotography of the deformed metal surface. Now in this paper, the mechanical characteristics of lubricant trapping has been proposed on the basis of the observation of a cross-sectional shape of the metal surface which is constructed from Talysurf record. Further the lubrication mechanism of metals and alloys is decided and shown in detail by the diagram.
An experimental analysis is given in which the surface asperities of a deformed specimen depends on the film thickness of lubricant, the trapping rate of lubricant and the roughening rate of free surface during deformation when the initial surface is flat. The high friction observed in the cace of bearing steel and high speed steel, and the low friction in the cace of aluminum, iron and stainless steel were all assessed by the results of experimental analysis mentioned above. It is found that the materials with the high coefficient of friction had thelow values of trapping, film thickness and roughness, and the materials with the low coefficient of friction had the high values of the same. In order to test the effect of flow stress, experiment is carried out, using the Vickers hardness H_v of the metal surface (H_v is substituted for the flow stress). It has been concluded that the behaviour of surface asperities varies according to the trapping, film thickness and roughness, and these are not related to the flow stress, which suggests unsolved problems for this relationship.
In another result, the grain size of the annealed bearing steel could be measured by means of the light-compression method with semi-solid lubricant.

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The mechanism of chip formation on turning with a self-propelled rotary cutting tool is complicated as compared with a conventional type. In this paper, the rotation of tool, the contractibility of chip, the flow angle of chip, the sectional form of chip and the normal shear angle are experimentally investigated. Furthermore, the mechanism of chip formation is analyzed in comparison with that of the same tool with the fixed edge.
The results obtained are as follows.
1) The normal shear angle of the rotary cutting tool is less than that of the tool with the fixed edge and the contractibility of chip is larger. These results are considered that the section area of chip is smaller and the chip is lengthened to the flow direction of chip, for the decrease of chip pile up rate in a plane perpendicular to the cutting edge, that is, the increase of chip flow angle is larger as compared with the increase of chip thickness.
2) The tool rotation varies by the friction of tool mount, the affinity of tool and chip interface and the property of workpiece and so forth, but these influences are less. The tool rotation is mainly determined by cutting speed and inclination angle of tool.

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In this report interference phenomenon between a grain groove and grinding force with the single grain passing through close the groove is researched theoretically and experiment-ally. Assuming that grinding force with a single grain consists of ploughing force and friction force, the factors which control grinding force may be approximately given with dynamic yield pressure of workmaterial, ratio of piling-up area, net contact area, friction coefficient and contact ratio between tool and workmaterial. Applying these factors, specific grinding force defined as grinding force per theoretical chip area can be shown as a function about pitch ratio γ, distance between ajacent tool-groove normalized by theoretical width of the groove. This theory approximately agrees with the experimental values obtained with a pyramidal diamond tool. To put this briefly, specific grinding force remains constant in approximately γ>3, but varies according to γ in approximately γ<3, taking the maximum value in γ≈1.51.7, the minimum value in 0.81.0, remarkably increasing as γ decreases furthermore, in other words, interference phenomenon is caused. The abovestated results suggest that interference phenomenon has much effect on abrasive working force.

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The two theories gave a nearly satisfactory solution for a problem about the mysterious flexibility shown in high-energy-rate-forming of a hard metal. The one is the deformation theory of zero-thickness-plate under lateral impact, and the other that of strain-wave-stracture which states about the thickness-criterion indicating the limit of application of the zero-thickness-theory, using the strain-wave which is deduced from the same theory. But it was found afterwards that the theoretical wave form differed a little from the observed one. And to clean up discrepancy and related conflicts, New Deformation Theory has been developed, under the consideration of the plate thickness δ₀. The main results are summarized as follows:
1. If we consider merely the changing profile of a thin plate, its deformation is well explained by the theory of zero-thickness-plate.
2. If the strain of plate comes into question, there must be considered the longitudinal elongation infront of the material point where the maximum curvature K₀ occurs. The strain e is given by: ε=1/2K₀δ₀(δ_c/γ_c-γ)²(γt/ξ-γ/γ_c)², where : the velocity of propagation of the maximum curvature K₀ along the plate, γ_c: that of sound, ξ the original coordinate of the specific particle-point on the material-plate, and t: the time measured from the instant when the impact begins.
3. In the portion by where the maximum curvature has past, the strain ε increases from 1/2K₀δ₀ to 1/2(U/c)², where c: the horizontal velocity of propagation of the maximum curvatureK₀ relative to the space-fixed-coordinate-system, and there the deforming motion occurs almost entirely in accordance with the theory of zero-thickness-plate.

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In this paper a frequency response analysis of a hydraulic feed system of machine-tool is described and a method to improve the dynamic characteristics of the system is developed. From the basic equations given in the previous paper, a transfer function of the table motion is introduced. The experimental analysis for the frequency response gives a good agreement with the theoretical analysis and from this result it is made clear that the basic equations are also valid for the frequency response. The frequency response obtained indicates that the dynamic behaviour at the table characteristic frequency region is the most important problem in the hydraulic feed system. Considering this result, a method in which the internal leakage in the cylinder is used to improve the dynamic bahaviour at the table characteristic frequency region is discussed both experimentally and theoretically. The result obtained indicates that this method is effective for the purpose.

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Described in this paper, is a pneumatic method of gauging a very short length placed in a vacuum room. In this micrometer, air flows from the atmosphere into an intermediate chamber through a filter and an orifice, and then leaks into the vacuum chamber through a measuring nozzle. The variation of the gap between the nozzle and its counterface causes the pressure change of the intermediate chamber. Both static and dynamic performance of the micrometer is concretely studied with experimental examples.

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In this report, as one of the study on the elastic modulus of grinding wheel, the correlation between the elastic modulus E_R measured by the ultrasonic forced vibration method which give the dynamic forces and the components of abrasive stones is discussed. And then, the elastic modulus E_P and E_S are respectively measured by the ultrasonic pulse method with the semi-dynamic forces and the compression test with the static forces. The differences in the elastic modulus obtained by these methods are also discussed.
A summary of the results is shown below.
(1) The elastic modulus is influenced on the volume rate of abrasive stone's components.
(2) The correlativities between the abrasive stone's components and the elastic modulus E_R, E_P are better than E_S. And the elastic modulus E_R agrees very well with E_P, but E_S is slightly different from the others.

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