The rate of isothermal transformation for 0-4% C steels containing about 1 % of tungsten, molybdenum, aluminium, tin, vanadium or cobalt, and 0.31 % of titanium were measured and the beginning and ending temperature curves i.e. S-curves were determined by dilatometric and metallographic methods. By addition of tungsten, molybdenum or vanadium (also chromium in the 1st Report) the S-curves are modified in pearlite range. By utilizing magnetic analysis, the magnetic critical points of carbides separated in several isothermal transformation temperatures were studied, and were certificated that the modifications in S-curves are due to the difference of carbides, which are separated in the transformation temperatures, that is, carbide separated in the lower part of pearlite range is cementite, while that in the upper part, other carbide or double carbide though the chemical formula or atomic structure is not determined. Cobalt, aluminium and tin which does net form carbide or double carbide in steel, does not modify S-curves ; titanium form stable carbide TiC but any modification of the S-curve is observable.

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Two methods to measure the thermal conductivity at high temperatures are experimented on some insulating materials. A direct heating method is found to be applied to the range of relatively low temperatures as 100° or 150° and to have a defect in its bad accuracy, though it is supperior in its simple and easy construction. Another method measuring the thermal conductivity by sine periodic heating has been applied satisfactory to a high temperature up to 1300°. This sine periodic heating method shows satisfactory results in its accuracy at the above given high temperature, for the phase difference of _any two sine-waves in the specimen tested by this method is good for calculation of the conductivity and the lateral heat flow in the specimen has very little effect on its value.

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Die theoretische Entwicklung des rontgenographischen Span nu ngsmessverfahren s and das strenge Messverfahren aus der 360° rotierenden Senkrecht- and ruhestehenden oder schwenkenden Schragaufnahme verdankt man viol der Glockerischen Schule zu Stuttgart. Wie in Japan aber Nishihara and Kojima das Messverfahren aus der Senkrecht- and Schragaufnahme, in der die beiden Filme ruhestehen, entwickelt haben, hat der Verfasser dieses Messverfahren zu einer theoretisch noch genaueren Methode zu führen beabsichtigt, so dass eine beliebige Komponente der Oberflachenspannung durch ein Paar von den Senkrecht- and Schrägaufnahmen mit genüigender Genauigkeit bestimmt werden kann. Der vorliegende Bericht besteht aus dem folgenden Inhalt:- I. Einleitung. II. Formelzeichen and Grundgleichungen III. Naherungsmessgleichungen. IV. Strengmessgleichungen (mit besonderer Berucksichtigung auf Aluminium-Legierungen) and Messverfahren. V. Schwenkungskorrektion. VI. Zusammenfassung.

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The durability of a cutting tool depends not only on the strength of its cutting edge, but also greatly on the rise in temperature due to the friction resistances and the cutting force at the contact parts of the cutting edge and the surface of steel to be cut. In the present study, four different kinds of high speed steels have been used and three kinds of materials have been chosen to cut. The following facts have been revealed in this experiment : (1) The increment of cutting speed, of cutting depth and feed, raises the cutting temperature quickly at first, but thee rate of the rise in temperature rise retards after a certain degree reached. (2) The rate of the rise in temperature differs with the shape of the cutting edge as it does with the cutting force. (3) The machinability of materials can be surmised from the rate of the rise in temperature. (4) The rise in temperature on the bite is nearly proportional to the cutting force, but not always to the durability of the cutting tool.

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