It was discovered that electrical contact resistance between graphite and finished surface or steel is abnormally high. The purpose of this research is to clarify the cause. The author measures the resistance of the metals finished by various methods, and electron diffraction patterns are leferred to this. He concludes that the abnormal resistance is due to oxides, and in steel, γ-Fe₂O₃. Further, he discusses the resistance of metal surfaces in reference to conductivity of their oxides, film thickress and breakdown of oxide films.

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The present investigations were projected to examine the effects of surface stresses of the mild steel specimens caused by milling on their deformations due to annealing. The results of experiments are as follows :
1. In this case surface stresses were tension.
2. Comparatively large amount of deformation due to the relief of the surface stresses appeared during annealing.
3. 680°C of annealing temperature was proved to be high enough to relieve the stresses.

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This paper presents some important notes obtained from a basic analysis of heat generation and dissipation during the orthogonal turning at elevated temperatures.
As the cutting velocity, thickness of uncut chip and temperature of work piece increase, the increase-rate of the mean temperature in a zone where shear for chip formation takes place is reduced and makes the mean temperature near to that of work piece.
As the temperature of work piece gets higher, that of tool-chip interface approaches it, and changes in cutting conditions do not have so much effect as at room temperature. The heat generated in cutting at high temperature, which is much less than that at room temperature, flows scarcely into the work piece and tool.

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Statistical Surface Analyser does not show the profile curve of the surface, but it catches the statistics of the population of the surface unit.
The purpose of this apparatus is to sample the surface unit, and the standard deviation and the skewness of the distribution of the surface unit can be estimated from these samples.
In this report, the principle and the capacity of this apparatus, the statistical quality control system of the surface unit and the model case of the measurement of the surface asperity with this system are shown.
The benefits of this apparatus is to be manufactured very easily, and be got the results in a shortest time.

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By measuring cutting resistance and shear angle, shear stress at the slipping plane in cutting was calculated. And the cutting phenomenon was analysed by applying the new theory of cutting.
1) Shear angle increases with the rise of rolling reduction and the containing percentage of Pb.
2) The equation φ+β-α=C' was proposed. Variation of C' among the various brasses was not so much as that of the machining constant C by Merchant.
3) C' depends on the relation between brittleness and shear strength of material te be cut.
4) Shear stress at the slipping plane changes in proportion to the product of shear strength and shock value of Charpy's test.

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