The strain acting upon the belt was measured by means of detecting the electrical signal from the strain gauge, contacting with the serrated contact wheel, pasted on the inside belt as mentioned in the 1st report. It was found that as the gauge located on the land of serrated contact wheel, the strain values had been able to evaluate the grinding ability caused by the different surface velocity and the hardness of the serrated contact wheel. In this paper, the ratio of the effective depth of cut to setting depth of cut Z is used to explain the relation between belt tension P acting in grinding as an example. The main results are as follows.
(1) In the various surface profiles and the surface velocities of the serrated contact wheels, P is nearly increased in linear proportion to Z but each tendency is defferent quantitatively.
(2) The relation between P and Z is affected very much with the spring constant because of the relation between the belt tension P' assumed having same spring constant considered various rubber hardnesses and surface profiles of the serrated contact wheels and Z has nearly one proportion.

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There are two contact phases in roll forming process. One is the conjugate action between the roller tooth and the blank tooth. The other is the non-conjugate action between the tip edge of roller tooth and the fillet surface or the bottom land of blank tooth. In the reports of this type published to date the operations are classified as the rough and the finish rolling because of the amount of material that must be moved by the rolling. But in this report the operations are classified by the above contact phases, and the experimental consideration is done to get the effect of phases on the pitch error and the profile error for the module m 3, spur and helical gears. The following results are obtained: If the gear blank meshes with dies holding conjugate action during rolling, the accumlated error after rolling is 5 to 20 μm, and the profile error is 13 to 20 μm, where the material used is JIS S 20 C steel, the tooth depth of pre-gashed blank is 6.0 to 7.0 mm in range. But in the same condition the material and the pre-gashing depth the non-conjugate action at the fillet surface of the blank tooth may be inserted into the process, the accumlated error after rolling becomes 10 to 20 μm, the profile error becomes lower grade 20 to 30 μm. After rough rolling, the rolled gears are further processed by finish roll holding conjugate action. In this case the accumlated error held the same level, but the profile error is improved 15 to 20 μm, though 40 μm in rough rolling. Further, when the rough and finish combined rolling is applied to the high hardness metal JIS S 55 C steel, the profile error is improved higher grade 5 to 10 μm.

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The study appears from the going discussing that the metal physical properties of the chip may allow a deeper insight into the morphology of the chip produced by use of dislocation theory. An experimental investigation has been carried out with the aim to analyze, in some detail, the general facts under which the chip tensile strength and hardness change occur. And it describes to fundamental relation of the micro- and macro-chip formation mechanisms on polycrystalline aluminium of high purity (99.78 and 99.998 percent aluminium). The main results obtained are summarized as follows.
(1) The tensile strength σ_B of the chip increases from 2 to 6 times value of the bulk. The fact is investigated by the dimension of the very small magnitude dimple pattern in the fracture surface.
(2) The lamellae of the chips are always generated perpendicular slip direction <111> to chip flow direction in micro- and macro-chip formations. And the minimum lamella slip spacing was the order of 100-150 atomic planes spacing.
(3) The shear stress τ_av of the macro-chip formation process developed by Zwolkin-Piispanen-Merchant is in good agreement with value calculated of the average shear stress for polycrystalline aluminiums using a dislocation theory in the micro-chip formation.

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In this paper, the topography for external surface of a grinding wheel after dressing is given by replica method, under the dressing feed f_d=25 μm/rev and f_d=250 μm/rev. From this topography, the relation between dressing feed and distribution in depth of cutting edges formed on wheel surface by dressing operation is shown and the numbers of grains remaining on the surface after dressing operation are drawn. Otherwise, the numbers of grains existing on an ideal section of an actual wheel are calculated, and these results are compared with experimental results. The main results obtained are as follows:
(1) Distribution in depth of cutting edges formed by dressing operation is nomal distribution, and dressing feed influences the standard deviation and the shape of a wheel surface.
(2) Abrasive grains remaining on a wheel surface after dressing operation are about 52% of all grains to exist on the surface, and dressing feed scarcely affects this value.

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On the superfinishing stone of fine grain, soft grade and sulphur treated, which have been recently employed to comply with the request for high stock removal together with lowest cost and high quality surface, an efficient utilization of the critical stone pressure P_c is emphasized again in this paper as an important characteristic concerned with actual performance for an advanced selection and manufacture of the well-fitted stone for the object. Chiefly from the finishing data of the bearing steel with stones of WA 3000 V (S) having various structure and hardness, the relations are discussed between stone specification and P_c, stone wear rate W_c/P_c, stock removal T_c or economic ratio T_c/W_c at the pressure of P_c. Consequently, it is proved that the user can almost appoint the right stone which holds excellent performances coincidently in T_c and T_c/W_c by P_c and the Rockwell hardness RH of the stone. In practice, this stone is desirable to be applied at the pressure of (0.8-0.9) P_c, for example, to secure a mirror finished surface of high quality and a stable stock removal. Furthermore, the universality of relationships between stone specification and the above characteristics and the possibility of selecting a fitted stone by the above procedure are checked up with three different examples in grain size, working material or conditions.

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In chatter vibration during cylindrical grinding, the workpiece vibrates with considerable amplitude. In this paper, the amplitudes of chatter vibration in other elements, i. e. wheelspindle, wheelhead, headstock, tailstock and table, are experimentally observed and the dynamical system with eight degrees of freedom is established, considering the results of rigidity measurements and resonance curves. As a function of an equivalent spring, coupling the grinding-wheel and the workpiece, the frequency of workpiece is computed and compared with frequencies of systems with lower degrees of freedom, in which the motions of elements with smaller amplitude are neglected. As a result of analysis, it is indicated that the behavior of workpiece can be evaluated in its own system, including coupling stiffness. Further it is shown that the workpiece, which is held between centers, acts as a mass supported on springs and also possesses a spring characteristic as a beam, and by means of Transfer Matrix method the mode of vibration of workpiece system can be obtained, which lies closely to the experimental one.

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Ferrite plates were rubbed against the cast iron disk on which the oil containing the abrasive grains (1000 or 4000 mesh) was supplied and wear of ferrite was studied. An olive oil was mainly used. A kerosene was also used in some experiments. Wear amount is directly proportional to the sliding distance. Wear rate α (mm/mm) generally varies linearly with the contact pressure P_n, although the α versus P_nrelation for the 4000 mesh grains in olive oil exhibits a breaking at a pressure of about 400 g/cm². When the 1000 mesh grains are used, the variation of wear rate with the crystallographic plane of ferrite is clearly observed and the degree of wear resistance is as follows: (100)>(110)>(111), (211). When the 4000 mesh grains are used, the wear rate is slightly dependent upon the crystallographic plane. In case that both abrasive grains are used, the wear rate of polycrystalline ferrite is greater than that of single crystal ferrite. This seems to be due to the occurrence of brittle fracture at the grain boundaries of polycrystalline ferrite. The values of the coefficient of wear are of the order of 10^-5 mm³/kg·mm for the 1000 mesh grains and of 10^-7 mm³/kg·mm for the 4000 mesh grains, respectively. An electron microscopy of ferrite worn surfaces suggests that wear on the 1000 mesh grains is mainly due to the brittle fracture such as cleavage and quasi-cleavage, while wear on the 4000 mesh grains seems to be mainly due to a plastic deformation such as micro-cutting.

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The static, thermal and dynamic deformations of the machine tool structure are measured by means of holography. The whole optical system for laser holography is placed on the heavy reinforced concrete block supported by several air cushions. The double exposure method is used in the static and thermal tests, while the time average method is used in the dynamic tests to obtain the mode shape and vibration amplitude of the structure at a resonance frequency. The transient thermal deformation of the structure is evaluated by taking the interference photographs at a certain interval during the cooling-off period of the structure and by assembling these results in the preceding intervals. Holography is also proved useful to examine the mechanical behaviors of the machine interface.

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When particles are conveyed along a helical trough attached on a circumference of a cylindrical bowl, motions of these particles are influenced by centrifugal force being pressed on the inside surface of the bowl. In this case, the equations of motion are expressed by non-linear differential equations as the centrifugal force is proportional to the square of the particles velocity. The mean conveying velocity can be calculated numerically by digital computers, and the conveying velocity factor V which was defined already in the previous report can be also calculated. V becomes the function of four dimensionless quantities, while the conveying velocity factor in the linear direction conveying is the function of three dimensionless quantities. The 4th factor R is a quantity which is proportional to the ratio of vibration amplitude a to the radius of the bowl r. Some theoretical results are shown in various diagrams. These results show that the influence of bowl-wall is small when a/r is small which is usually the case, and the conveying in bowl type conveyor can be approximated by linear direction conveying, which is a developed helical trough. It is confirmed that the experimental results agree well with the theoretical ones.

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Dissolution mechanism of stainless steel is investigated experimentally on Electro-chemical Machining using sodium nitrate solution. The results are as follows.
(1) The kinds of gas generated in the working gap are mainly oxygen from anode and hydrogen from cathode. These gases are generated by the electrolysis of water in machining.
(2) Valencies of work material in dissolution are 3 for iron and 6 for chromium.
(3) NO₃ ion in the electrolyte is partially reduced as the proceeding of the process, and then NO₂ and NH₄ ions are generated in the electrolyte.
(4) The quantity of the generating gas obtained from experiment is less than the calculated one from the experimental value of current. The quantity of the generating gas from unit machining area and in unit machining time is influenced by flow rate, while it is not influenced by electrolyte temperature and applied voltage.
(5) The rate of the oxygen gas in all generating gas from unit machining area and in unit machining time increases with the increase of electrolyte temperature.

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This report describes the trial manufacturing of a screw lead measuring machine with laser interferometer and its characteristics, comparing with the first trial machine. The measuring capacity for a thread length of a screw to be measured is 1 m, while it is 500 mm in the first trial machine. The other characteristics are as follows: (1) The optical system is improved to avoid the back talk of laser. (2) In the electronic circuit, the correction circuit for atmosphere and DA conversion circuit for simultaneous digital and analog recording are added. (3) Beside the function of the measurement of cumulative pitch error, the functions of the measurement of lead error of screws and nuts are added, where the lead error is the combination of cumulative pitch error and cyclic error. (4) The reproducibility of measurement is expressed by a standard deviation as follows: 0.3 μm for the measurement of cumulative pitch error of ground screw having thread length of 800 mm, 0.2 μm for the measurement of lead error of ground screw having thread length of 250 mm and 0.4 μm for the measurement of lead error of cut nut having thread length of 80 mm.

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This paper describes first, the exo-electron emission phenomena from the heat-treated abrasive grains. And then the effects of the exo-electron emission from the grains were examined on the affinity between the reginoid bond and the grain-surface. Second, the exoelectron emission phenomena from the diamonds and the CBN grains were compared. The main results are as follows:
(1) Al₂O₃ series grains which were heat-treated at temperature of under 600°C gave a strong emission intensity, but SiC series grains gave no emission without regard to the heat-treatment.
(2) The grade of the reginoid wheels baked with the Al₂O₃ grains which were heat-treated at temperature of under 600°C was weaker than that at temperature of over 600°C, but the grade values of the reginoid wheels with the SiC grains which were heat-treated at 200°C and 1300°C were same. Because the exo-electron emission from the grains when the wheel is baked will interrupt the affinity between the bond and the grain-surface.
(3) The man-made diamonds gave a weak emission intensity and the nature diamonds gave no emission. But the CBN grains gave more stronger intensity than that from WA grains. And a spontaneous emission occured even at normal temperature from the fractured CBN grains.
(4) It was suggested that in grinding process the exo-electron emission influenced on facilitating of bite of cutting edge on metal surface, and on adsorption of grinding fluid to the metal surface.

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Basing on the experience that the plastic strain distribution produced in the indentation process is similar in its pattern to the maximum shear stress distribution obtained from the elasticity theory, the formulation for the indentation strain can be derived. Such a strain may be dealt with the same manner as the elongation or contraction produced by the single axial load. If the material of specimen is known, the indentation strain is determined by the shape of indenter and the amount of indentation. Particularly for the cone indenter, the strain is defined by only its angle of apex. The strain in the spherical indentation is given in the form
ε_s0 = 1/K_s · E/π (1 - ν²) · α/R_s
The work-hardened index obtained by using such a strain expression is similar to that usually observed in the tension test.

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