Stress distributions in two normally intersecting cylindrical shells subjected to internal pressure are discussed on the basis of Donnell's equation for the intersected shell, and Flugge's equation for the intersecting one. A rational boundary condition along the intersection curve is derived by using Energy Principles. Numerical computation was conducted, and the results are compared with experiments.

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This paper is devoted to the microscopic observation and hardness tests on the surface of metals fatigued at ultrasonic frequency (17.8 kc/sec). It was found that, in iron and steel, microcracks were initiated at the boundaries of pearlite and ferrite without any accompanying slipbands. This is in marked contrast with the surface structure seen in those metals fatigued at conventional frequency. In copper, however, no marked difference between both was observed. Micro-hardness of iron failed by fatigue at such a high frequency remained almost equal to that of the annealed state, while that of copper increased as seen in the specimens fatigued at conventional frequency. Results observed above are discussed from a point of view of the strain rate dependence of unidirectional deformation behavior of b.c.c. and f.c.c. metals.

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The time and temperature-dependent ultimate properties of an unfilled SBR was investigated at several strain rates and at ten temperatures between 40 and -57°C. The results obtained are as follows : 1) The time and temperature superposition of the ultimate strain of an unfilled SBR is almost the same as given by W.L.F.'s equation. 2) For the tensile stress at break, the superposition could not be admitted without consideration of the effect of the testing strain rate in respect to the local disproportion of deformation of the cold drawing, especially at low temperatures. 3) The time and temperature-independent failure envelope of unfilled SBR seems to suggest two different types of fracture mechanism. One will be predominant for the fracture of SBR when the material behaves rubber-like at high temperature and another when the material behaves viscoelastically at low temperature. And the substitution of predominance occurs at a particular condition of strain rate and temperature.

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The main requirement for practical photo-viscoelastic analysis is optical and mechanical characterization of the material, which has a strong time and temperature dependence of mechanical and optical properties. It is assumed that polyurethane is a linear-photoviscoelastic material and the correspondence rule for mechanical behavior proposed by Alfrey⁽¹⁾ can be also applied to optical behavior. The birefringence and stress or strain were measured simultaneously under two conditions, one being constant strain rate and the other being constant load. From experimental data, the stress-strain and the stress, strain-birefringence relations were obtained and the coefficients on the Laplace transformed plane of time were calculated. Based on this calculation, a new method of approximation of Prony series was proposed. The result calculated using abovementioned technique from constant strain rate data is well corresponding to the directly calculated result from creep testing. Therefore, it is found very good to apply the theory of linear-photo-viscoelasticity to this material.

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The authors have proposed a new moire method of measurement of plastic strain. The method is based on the principle that the common tangential direction of two interference fringes coincides with the direction toward which the normal strain vanishes, when the master grid is composed of two families of strainght lines. The authors have also suggested a new technique for the calculation of strain which reduces the errors of the measurement by applying the gridwork method. These two methods are applied to the experimental analysis of the plane strain extrusion and the axi-symmetric extrusion. From the experimental results, it has become clear that the undulations of the distribution of the strain and of the hydrostatic pressure become less with the decrease of the die angle or with the increase of the reduction of area. The experimental results of the plane strain extrusion show good agreement with Hill's solutions concerning the non-hardening material in regard to the velocity field, while the experimental results of the axi-symmetric extrusion also show considerable agreement with the authors' upper bound solutions.

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The vibration of a thin cylindrical shell is studied through the method of minimizing the Lagrangian of the vibration of a cylindrical shell. The frequencies and the modes of the cylinder with three supports are obtained and the frequency equations and the frequencies of single cylinders with some boundary conditions are also shown. The method mentioned above is useful to treat the vibration of such systems which have various boundary conditions, or the system consisting of a cylinder and some elastic bodies.

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In this paper, at first, an approximate theory is developed for the mixed-flow turbomachines based on the boundary value problems. The relations between the cascade characteristics and the geometries can be very easily determined by the theory. Then, for the variable-pitch reversible pump-turbines the characteristic diagrams of twelve rotors are obtained to examine the effects of the blade camber and the passage-angle.

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For a viscous fluid flowing very slowly near a pipe inlet and exit when the mass forces of Navier-Stokes equations are negligible, the author solved strictly the equations of motion and obtained the stream function, the velocity distribution, the coefficient of skin friction and the pressure gradient. The results are as follows. (1) When the radius of a rounded pipe is large, the velocity distributions at a straight pipe entrance are near-parabolic. When it is small, they are close to the mean velocity profile. Also, when it is zero, i.e. the entrance is square-edge, the streamlines and the velocity distribution agree with Sampson's solution for a thin orifice. (2) The pressure gradient on the rounded pipe surface is large near a straight pipe inlet, and is small at a large distance from it. Either for inflow or for outflow, separation can not occur as the pressure continues to decrease due to viscosity.

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A new method is proposed for the calculation of radiative heat transfer in the case where the gray gas is contained by a three dimensional furnace and has a heat source. The walls are gray and have each the same temperature. The author tried to calculate the emissive power and temperature distributions of gas and the heat absorption rate of the walls. The calculation was conducted by the Monte Carlo method and programmed for electronic digital computation. The following examples were calculated by computer ; the results affected by the scale of the furnace and the emissivity of its walls, the results affected by the fullness and position of flame. Then, the author compared the calculated results of a thin gas volume with those of a onedimensional gas slab and checked the agreement between both results.

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Experiments have been carried out on a surface of water exposed to the flow of air of the range from 3 to 40m/sec in the velocity and from 30°to 175°C in the temperature. Measured items include not only the heat transfer coefficient, the profiles of velocity and temperature, but also the critical velocity of air for the stability of water surface. Results of heat transfer coefficient measured within the stable region of water surface are nearly in accord with the correlation proposed by Smolsky and Sergeyev, and the heat transfer coefficient becomes greater than that of a solid surface with a rise of the temperature of air. However, the profiles of velocity and temperature measured in the boundary layer are almost in accord with the 1/7 th power law, and it seems likely that they are not affected by evaporation within the range of the present study. Increasing the velocity of air flow, there appears a point at which an abrupt increase in loss of water begins. The velocity of air at the critical point agrees well with the following, wellknown value if the evaporation from the liquid surface is weak. [numerical formula] However, as the temperature of air is raised to cause an increase of evaporation, the deviation of the experimental result from the theoretical value becomes noticeable. It should be concluded, therefore, that the liquid surface subject to evaporation has some peculiarity with respect to the critical velocity for its stability too.

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A new equation of state for steam was formulated for the range of temperatures from 0 to 800°C and of pressures from 0 to 1000 bar. This new equation, in which the specific volume is expressed as the function of temperature and pressure, has a relatively simple form of polynomials and is suitable for computer calculations. This equation was transformed into a nondimensional canonical form (the equation of Gibbs function) from which various derived quantities such as the specific enthalpy, the specific entropy and the specific heat can be obtained by differentiation only. Calculated values of the specific volume and the specific enthalpy agree with the values of the new Skeleton Tables (1963) established by the Sixth International Conference on the Properties of Steam held in New York. The new equation of state and derived functions as well as tables of calculated property values are shown in this report.

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By using dual-number quaternion algebra, the necessary and sufficient condition for the spatial four-link chain having four cylindrical pairs to be constructed is formulated as eight equations. On the basis of these equations, new one-degree-of-freedom mechanisms having two turning pairs and two cylindrical pairs are presented. Moreover the condition for the driving link of the spatial four-link mechanism having one turning pair and three cylindrical pairs to be movable and the condition for this link to make a complete revolution are established.

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When synthesizing those mechanisms whose driver links make full rotations, it is necessary to examine whether the drivers can make full rotations and whether the mechanisms transmit motions well. In order to examine those problems of spatial mechanisms, however, complicated calculations or constructions should be done repeatedly. So, simple methods to know the rotational conditions of the drivers and the transmissibility of motion have been considered. Namely the pressure angle is adopted as the criterion of the transmissibility, and the relation between the pressure angle and the rotational conditions is discussed, citing three kinds of spatial four-bar mechanisms as examples. The pressure angles are expressed in analog circuits.

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Die Funktionsgenauigkeit einer Werkzeugmaschine ist von ihrer statischen und dynamischen Steifigkeit abhangig, weshalb die Steifigkeit bedeutend fur die Werkzeugmaschinen ist. Im allgemeinen sind zwei Arten von Steifigkeit uber das Gesamtsystem, d.h. die Werkzeugmaschine, namlich die Steifigkeit der Einzelelemente und die Steifigkeit der ruhenden und beweglichen Verbindungsstellen. Das Problem von der Verbindungssteifigkeit ist aber bisher kaum behandelt worden, obwohl es von Bedeutung ist. So wurde die Untersuchung uber die Steifigkeit an den Verbindungsstellen, die nach ihrer Form klassifiziert wurden, durchgefuhrt. Im vorliegenden Referat wird besonders uber die Biegesteifigkeit der verschraubten Fugen auf einer vorhandenen Langhobelmaschine berichtet, und die Versuche konnen klaren, ob und in welchem MaBe die Eigenschaften der verschraubten Fugen auf das Steifigkeitsverhalten beeinflusst werden.

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Several types of sensor for detecting tool wear of both on-line and semi-on-line performances are reported. As for a parameter for an on-line sensor, variation of cutting force and relative displacement of machined surface due to flank wear have been experimentally proved to be adequate. The proportionality constants of the relations between cutting forces and wear lands have a close and simple correlation with the physical properties of the work materials. The continuous measurements of flank wear by way of the relative displacement of the machined surface are also highly reliable for an optimizing control of a lathe in view of tool life. In order to obtain more direct information of tool wear, an electro-optical measuring device has been also developed.

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Metal cutting process was investigated from the view point of generation of new surface and hence in association with machined surface characteristics. Discussions were made on the ploughing force on the extreme cutting edge, the depth of the distorted surface layer and the work absorbed in its generation in order to reveal the relation between generating process of ploughing force and surface layer. Following conclusions are drawn from the present study. 1. A part of the ploughing force consists of the force exerted in generation of distorted surface layer. 2. The work done by cutting edge is from 4 to 7 per cent of the work of all cutting operation under normal cutting conditions. 3. The depth of distorted surface layer in actual cutting is nearly equal to that of theoretical plastic zone which is calculated on the assumption that the ploughing force acts as a concentrated force on the semi-infinite surface of work-piece.

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In the deformation processes in a pneumatic high speed hammer, friction is very low. This is due to the fact that much liquid lubricant is trapped between the tool and the specimen. In this paper, the mechanism of lubricant trapping under dynamic compression is analyzed with hydrodynamics and flow stress of the specimen material. The pressure distribution and the thickness of trapped lubricant film are calculated. The film thickness (h) is affected by compressive velocity (V), viscosity of the lubricant (η), diameter of the specimen (R), and flow stress of the material (p₀). These are correlated as hocV^1/3η^1/3R^2/3p₀^-1/3. Compression tests are carried out using a high speed hammer in order to ascertain the analysis. The experimental results agree well with the analytical results. It is found that most of the trapped lubricant remains entrapped even after a large deformation.

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