The surface structures of a single crystal silicon finished by the electrolytic buffing method were investigated with abrasives added to 4% HF solution. The results obtained were as follows :
(1) The single crystal silicon of very smooth surface and almost free from work damage was finished by electrolytical and mechanical action. The mechanical action was obtained by using a portion of insoluble SiO₂ abrasives in the solutions.
(2) With all the SiO₂ abrasives dissolved in HF or Al₂O₃ abrasives added to 4 % HF, the surface finish by electrolytical action was not smooth, and etch pits were seen on the whole surface.

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In the earlier study the wear and metal removal in single grain wear test have been investigated on many grain-work combinations. On the other hand, a series of plain fly milling test have been made to evaluate the resistance of grain to micro-chipping on the same grains and works, but in this research the metal removal, or G-ratio, has never estimated. In the present paper the numerical results of the G-ratio are presented, which were obtained based on the previous experimental data on micro-chipping characteristic, provided that grain is a sphere. The ratio was determined as a function of depth of cut. From the result of G-ratio, the rating and the compatibility of grain to work have been discussed. The results obtained are summarized as follows : The G-ratio is seen to increase at first with depth of cut and reach a maximum at a depth of cut of 20 to 40μm. The maximum G-ratio ranges from 400 to 7000 in compliance with grain and work material. Specially, the grain type appears to much effective on the G-ratio. Roughly speaking, it is evident that the grain types of having high hardness and medium toughness, such as the 40 SH, the SH or the R 71 grains, have higher G-ratio than the highly friable grain types, the WA or the 2 A grains, and also highly soft grain, the AZ 40 grain, with the exception of the SUS 27 steel, where the tougher grain indicates higher G-ratio.

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Residual strains in ground layer of carbon steel were measured with change of incident direction in X-ray diffraction method. When X-ray irradiates on the ground work surface from the two directions corresponding to the front and the rear of abrasive grain, two sin² ψ-diagrams are found to differ from each other. These two sin² ψ diagrams have a certain fixed correlation with the grinding direction. This phenomenon concerning with the strain dependence upon grinding direction is concluded to be caused by the phase stresses originating between a ferrite and a cementite phase in a plastic flow layer of ground surface. Direction of one principal axis of the phase stresses agrees with the flow direction of the fiber structure in ground layer and is different from that of the macro-residual stress. Equation can be derived which expresses the relation among the macro-residual stresses, the phase stresses and the residual strains measured by X-ray. The macro-residual stress calculated by the equation agrees with the residual stress determined by removing lamellas on the stressed surface layer and following the changes in curvature of test specimen. Calculation shows that in ferrite phase there exists generally the compressive phase stress in the direction parallel to metal flow and the tensile one in the direction perpendicular to it.

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The moiré topographic method is a powerful means for measuring the height of protrusion and the depth of depression of a three dimensional uneven object. But this method is limited in its application just as various other measuring methods. In this paper, the property of the moiré fringes is reexamined from a visual view point. As a result of this study, it is found that an effectively measurable region exists in the conventional relation between the fringe interspacing and the inclination of the object. It is also ascertained that this effectively measurable region can be enlarged by changing the amount of mismatch of the reference grid.

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When ball screws are equipped in machines, there are many cases that the moment acts on the nut due to shaft weight and setting error and the both thrust and radial loads acting on the ball screw. In this paper, we dealt with the load distribution in the ball screw when the moment acts on the nut loaded by some thrust. After the various load distributions were analyzed theoretically, the results were ascertained by means of photoelastic experiments. Main results are as follows.
(1) The effect of the moment on the load distribution in the ball screw is large.
(2) In order to equalize the load distribution in the ball screw loaded by the moment, it is effective to set the first ball on the bottom position of the nut at the working side of radial load acting on the shaft of the ball screw in the axial loading condition of the T-T type.
(3) The theoretical values of load distributions coincide fairly well with the photoelastic experimental results.

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Electron beam welding of aluminum foil using transmission of electron through foil is newly developed. That is, the target is heated and molten by the electron energy which has transmitted through foil and then the foil is welded to the target. From the fraction of energy transmitted and the heat conduction theory, it has been made clear that an electron beam of higher accelerating voltage, larger beam current and smaller diameter is required for welding. Considering these conditions, the experiments were performed. As results, aluminum foil of 20μm in thickness can be welded to stainless steel and copper under the condition of accelerating voltage of 120 kV. Moreover, it is confirmed by the tensile test that the strength of the welded portion is higher than that of foil.

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This report proves that, by the result of analyzing the axial vibration drilling mechanism, the pulsating drilling force under the conditions of 2a>s/2, where a is amplitude, s is feed, and the other drilling force shown by the equation H (t) -H_mean+h sin ωt of 2a<s/2, have been acted on the drill point. Through the analysis of the dynamical behavior on the drill point under each condition, it is analyzed that the former proves the rigidity effect and the stillness effect for the latter. In experiment the actual drilling force can be measured by use of the drill dynamometer with high accuracy and high insensitivity having about 80 kHz in natural frequency and 5% in interference ratio divided in two forces. This obtained force can be equal to one analyzed. Thus, this result proves adequateness of the analyzed force and the theoretical basis of high accuracy drilling with the axial vibration drilling. And it is also found that the drilling accuracy becomes even more higher to apply the rigidity effect positively.

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This Paper describes the behaviour of dislocations and elements in chip and built-up edge, in order to investigate the mechanism of tool wear by means of SEM, TEM and EPMA. The results are as follows :
(1) A remarkable plastic deformed structure in chip and built-up edge have cellular structure and excessive dislocation density. Dislocation density, however, in the high cutting speed decreases due to the elevated chip temperature, and also structure shows dynamic recovery and recrystallization, and dissolution of cementite increases at the same time.
(2) Carbon in built-up edge goes into cohesion on the interface of tool by the short circuit diffusion under the low temperature. As the result, tool is carburized on the surface.
(3) Carbides of tool surface at the low cutting speed easily extract and fall down by the brittleness of carburized tool's matrix. On the other hand, at the high cutting speed, carbides go into a plastic deformation and decomposition by shearing strain and cutting temperature, and then tool's principal elements diffuse and transfer to chip.

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The process of grinding the workpiece that has a pulsative distribution of hardness is theoretically and experimentally analyzed to make it clear how the hardness pulse of workpiece affects the dimensional accuracy in plunge grinding. In such grinding the runout is generated on the part of hardness pulse and varies in amplitude through a grinding cycle. The runout begins to be generated simultaneously with the size generation in the matrix of workpiece. The amplitude of runout increases with grinding time in the sparkin state, becomes maximum in the steady state of the part of hardness pulse, and then decreases with grinding time in the sparkout state. The final runout remains on the part of hardness pulse after the effective sparkout grinding. The amplitudes of the maximum runout and/or the final runout are proportional to the amplitude of hardness pulse, and increase with the pulse width smaller than the critical value, becoming constant with the pulse width larger than the critical.

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The cause of grinding burn has been considered ascribable to the formation of thin metal oxide layer on the ground surface. In this study, the effects of heating temperature and the duration on the tint of finished surface and thickness of oxide film have been investigated for carbon steel. Furthermore, combining the temperature distributions in the grinding surface, with the oxidation rate laws thus obtained, the thickness of the film to be formed in the grinding process is calculated, and the tints of surface due to the film are also estimated for various grinding conditions.

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The influences of cutting tool shapes and cutting conditions were experimentally estimated by the shape coefficient of chip C_R which was proposed for the estimating factor of the facility of chip-excluding in the previous report. The results quantitatively shown by C_R agree with the facts already elicited empirically, and those results are as follows :
(1) The chip-excluding becomes easier as a rake angle and a side cutting angle of a tool become smaller, and a nose radius smaller than 0.8 mm is desirable.
(2) The chip breakers of widely used throw away tips are not effective for the lower feed than 0.1 mm/rev, and the larger feed than 0.2 mm/rev is desirable for the chip-excluding.
(3) In case the depth of cut becomes smaller, the feed larger and the cutting speed higher over the speed at which the built-up edge disappears, the chip-excluding becomes easier.

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For establishing reasonable grinding operations, it is a most important problem to evaluate quantitatively the redress life of grinding wheels in connection with grinding conditions. In this paper, the characteristics of redress lives of shedding type and of dulling type, which are evaluated with the occurence of critical phenomenon in wheel wear and of burn mark on a workpiece respectively, are discussed in connection with wheel grades, grinding conditions and dressing conditions. The results obtained are as follows :
(1) The redress life of shedding type T_C is expressed
T_C=1/-mN log elog {0.5F _(c) /F _(c) -F ₍₀₎ }
where F ₍₀₎ , F _(c) , m and N are the initial grinding force, the critical grinding force, a constant and the number of wheel revolutions respectively.
(2) The redress life of dulling type T_B is given by
T_B=1/-mN log elog {F _(b) -F _(c) /F ₍₀₎ -F _(c) }
where F _(b) is the critical grinding force corresponding to the generation of burn mark on a workpiece.
(3) The redress lives for different wheel grades, grinding conditions and dressing conditions agree qualitatively and quantitatively with the results derived from these two equations.

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A new measuring method is developed which can be applied to the measuring of the radial error motion of axis with a rotating tool. The measuring and cutting tests are conducted with a milling machine to verify this method. The measured radial error motions of axis are compared to the out-of-roundness profiles of the bore, machined by a diamond tool at the same conditions. The following conclusions are obtained :
(1) Radial error motion of axis is exactly measured by detecting the clearance between the master ball (used as a pickup device) and the small metal tip installed to the rotating axis.
(2) Radial error motions of axis measured by this method closely correspond to the out-ofroundness profiles of the bore, machined by a diamond tool.

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