No abstract

Metallurgical investigations such as recrystallization, martensitic transformation and dynamic behaviors of dislocations have been carried out with a 500 kV electron microscope. The critical foil thickness sufficient to observe the same dynamic behaviors of these phenomena as occurred in bulk specimens is about 1 µ for recrystallization in aluminum and iron alloys, and 3 µ for cell formation in aluminum. On the other hand, foil thickness which allows observation with the 500 kV electron microscope is practically above 8 µ for annealed aluminum and above 2 µ for annealed iron and copper, and it is about one half in order to allow continuous observation of the dynamic behaviors of phenomena. It is concluded that the 500 kV electron microscope has great advantages for the dynamic investigations of metals, especially of materials with the atomic number smaller than 15 such as aluminum and many of ionic crystals.

No abstract

A new instrument, Gonio-Microscope, has been developed which permits measurement of the direction of the normal to a plane surface with an area as small as 10×10µ2. The accuracy of the measurement is within ±0.5 deg. for a small component plane of an etch pit. A special feature of this instrument is that the measurement is made simultaneously with the observation of the position and shape of the plane being measured. This was successfully applied to the determination of grain orientation, structure of twin bands and slip bands, and the shapes of tapered cross sections of razor blades.

Note: ƒAE* and ƒÕ** are the deviation angles of rolling plane and direction from the indicated orientation, respectively.