Aluminium plates which have various inclination to rolling direction are cut orthogonally, and the cutting force and the shear angle are measured. Moreover, the anisotropic parameters and the γ-value are determined from tensile test of the same plates. Then, the effects of anisotropic nature on the chip formation are discussed from these results.
The main results are as follows.
(1) The cutting force R changes periodically against the plate inclined angle to rolling direction θ, and takes the minimum value near θ=0°, 90°, 180° and the maximum value at a middle of these. On the other hands, the shear angle φ changes in the reverse phase of R, and the ratio of its variation width to the mean value comes up to 50%.
(2) The slope angle of R to cutting velocity (β-α) is almost invariable for θ. Accordingly, the main factor bringing a large periodical change of R consists in the variation of φ.
(3) These phenomena can not be explained with the theory of plane strain, because of a different aspects of aluminium plate in relation between γ-value and 0 from, for example, steel or copper plate.
(4) The φ (β-α) relationship is almost ploted on a straight line distinguished only by θ, and is out of the solution by Merchant or Lee-Shaffer.

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Cutting of calcium deoxidized steel produces the thin film on the tool face. The aim of this experiment is to study the formation of the thin film and its effect in cutting mechanism. Three factors such as work materials, carbide tools (P 10, P 20), and cutting conditions can be changed, and the range of its formation on the tool face is studied accordingly.
According to the experiment, the thin film is found mountain-shaped, if exposed to the condition of constant feed. When the thin film becomes thickest in each result, the temperature of the tool surface is almost the same, without being much influenced by work materials and cutting conditions. Therefore, the formation of the thin film largely depends upon the temperature on the tool face.
Formation of the thin film reduces the frictional force on the rake face of a tool which results in decrease of the cutting force, increase of the shear angle and reduction of the tool-chip contact length. The results are experimentally proved with a specially prepared tool with gehlenite thin film. Cutting of calcium deoxidized steel is found better than that of sili-cium deoxidized steel in breakability of chips and tool wear.

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Machinability of the low and medium carbon steel deoxidized in different ways is investigated in turning with carbide tools. Ca-Si including three levels of Al and Fe-Si are used as the deoxidizer. The effect of sulpher contents on machinability is also examined. Experimental results show that deoxidation with Ca-Si including a proper amount of Al gives both kinds of the steel the best machinability and that addition of less and higher amount of Al to Ca-Si increases the tool wear. The steel deoxidized with Ca-Si shows better machinability a little than that with Fe-Si. It is also proved that higher contents of sulpher improve the machinability of the steel. These properties of machinability are discussed by observing the non-metallic inclusions in these steels and the formation of the thin film on the tool face in cutting.

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Characteristics of plastic deformation of metals, especially the flow stress with variable strain-rate, are discussed under such conditions that are encounterd in the plastic zone of metal machining. When strain rate are varied during deformation, the flow stress is not determined uniquely by the strain, strain-rate and temperature at the stage considered, but it is greatly affected by the strain-rate history up to that stage.
By using α-brass specimen and impact-compression testing machine, which was reported in the previous paper, the effects of strain-rate history upon flow stress are widely investigated. The results may be summarized as follows :
1. In order to analize the effect of strain-rate history, a new parameter “Equivalent, Static Yield Stress (σ_ES)” is introduced, which is defined as the static yield stress obtained by interruption of high speed deformation at an arbitraly stage of strain.
2. Flow stress of specimens having a same CES may be expressed by the following equation, regardless of histories of temperature, strain and strain-rate of the specimen.
σ=A (ε/ε₀) ⁿexp (α/θ) ·σ_ES
where A, n, α are constants, ε₀ is reference value of strain-rate and ε, θ are strainrate and absolute temperature at the stage considered.
3. While σ_ES is greatly changed by the strain-rate history, it is not affected by the temperature-history as far as heating time is short. For this reason, the effect of strainrate history, but not temperature-history, upon flow stress becomes major interest in such a high speed and high temperature deformation that is observed in metal machining.
4. A method for obtaining CES in the deformation with variable strain rate and temperature is proposed.

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An analysis is presented of the mechanism of contact between the smooth sphere and the rough plane; i.e., the relation between the load and the penetrating depth of the sphere. Applying this analysis, the influence of surface roughness, measuring force, work-piece material and the radius of the spherical-ended feeler on the accuracy of length measurement is discussed theoretically in the case of measurement of the flat work-pieces by the spherical feeler or stylus. A comparison of the calculated values based on this theory with the experimental data shows good agreement. It is found that the measured sizes are influenced mainly by early increase in the measuring force; i.e., from zero measuring force to a force of about 100 g. From theoretical and experimental consideration it would be expected that the larger the radius of the feeler the larger would be the mean measured size obtained by using that feeler. The variations in the measured sizes over an area of a work-piece owing to the effect of the surface rougness are likely to prove to be much more important than the effect of the radius of the feeler.

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This paper deals with the 'white layer' formed between tool and chip, and the reaction layer of diffusion. Three kinds of high-speed steel coresponding with SKH3, SKH4 and SKH5 were coupled with pure iron and diffusion annealed at the temperature of 600°1200°C for several hours. Then hardness measurements, microstructure observations and X-ray analyses were made on the diffused layer. These observations were compared with the white layer of cutting tool. Main results obtained are as follows :
(1) Chemical compositions of the diffused layer obtained at temperature of 900°1200°C for several hours were the same as the white layer formed when machining steel. By quenching the diffused layer was transformed to martensite structure.
(2) The temperature of the tool-chip interface is estimated at the temperature of 800°900°C by the tests, while the mean temperature by tool-work thermocouple method gives about 600°C.
(3) The formation of the white layer which includes alloying elements, expecially rich in C, Cr and V weakens the tool surface.
(4) Thiner diffused layers obtained with SKH4 and SKH5 containing much Co as compared to SKH3.

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Double flank meshing test is widely used because the mechanism and the handling of this tester are very simple. However, it is impossible to detect an worm cyclic error in a test gear by the conventional double flank meshing test with a standard master gear. In this paper we describe on the meshing test which aims to detect the worm cyclic error.
From the theoretical analysis, it becomes clear that if we use the profile shifted master gear with which a test gear meshes at the operating pressure angle φ=α0+π/2J_w (α0 : standard pressure angle, J_w, : number of waves in the worm cyclic error), the worm cyclic error can be clearly detected by the meshing test. The validity of the above theoretical result is confirmed by experiments.

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Described in this paper are dynamic characteristics of the pneumatic micrometer with both hybrid pressure cascade connection and feedback. The dynamic behavior of the measuring system is analogically presented as a 2nd order linear system, ie, both input and output circuits have time constants and transfer gains which change values as a function of the operating point. Damping ratio, natural frequency and equivalent time constant of the system are shown as a function of the output operating pressure and are further studied on an example how they are effected by the circuit parameters, such as the initial operating pressure, the coupling transducer gain, the feedback transducer gain, loading volume and compliances between the gauging nozzle and its counter-face. Means of adjusting the device to obtain required dynamic performance is discussed and it is demonstrated that measurements can be achieved with nearly constant and short response times, throughout the operating range, despite changes in output loading volume.

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