Alloys in the iron-chromium-molybde num-nickcl syste m were examined after qu enching from 2,200°, 2,000°, 1,800°, 1,650°, and 1,500° F. Composit ional l imi ts of s tability of se ven phases were summarized in diagram s. F e, Mo was foun d. to be a stable phase; and a ternary phase, not previou sly r eported, was identifi ed to hav e the approximate composition of 4 p ercen t of chromium, 53 p ercent of iron, and 43 p er ce nt of molybdenum.

Mono-and bicrystalline rods of copper were subjected to different degrees of cold-swaging and were examined with X-ray diffraction and metallographic methods. The results indicate that swaging causes the crystals to rotate until either an octahedral or a cubic axis becomes parallel with the rod axis. Whether the crystal assumes the octahedral or the cubic orientation depends upon which axis initially formed the smaller angle with the rod axis. Crystals approaching the octahedral orientation developed secondary crystals, after approximately 60-percent reduction in area. On further swaging, these secondary crystals approached the cubic orientation. Crystals initially approaching the cubic orientation remained one crystal after 95-percent r eduction in area.

The data from reports of 35 laboratories, comprising more than 2,000 analytical determinations, indicate that the vacuum-fusion method yields accurate r esults for the oxygen contents of plain-carbon steels either aluminum-killed, siliconkilled, or of the rimming type; the aqueous-iodine method yields accurate results for some types of killed steels and low results for other steels; more data, and particularly more concordant data, are necessary to define the accuracy of the other methods employed in this cooperative analysis.The vacuum-fusion procedures are reviewed and recommendations given for obtaining optimum results by this method. CONTENTS Page

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A photometric study was made of t h e refl ection of plane pol ari zed li ght no rmalh' incident in a metallographic microscope upon specim ens of tin, aluminum, and monel with variou s surface treatments. A high degree of correlation was found in most c9,se~ between the extin ction position and the projection of the optic axis or of the cubic axis making the greatest angle with the surface normal. Moreo ver, a fourth power sine relationship was obser ved between the change of intensity and t he angle between t.he s urface normal and the optic ax is in t in. The inte nsity correlation in the case of the cubic metals was not so clear, but a sli ght indication of position d epend ence was obse rv ed for a luminum . The res ults indicate that the optically anisotropic effects obser ved with cubic m etals can be caused both by an isotropic fi lm s a nd by oriented surface conto urs, but that the latte r is the source of t hose effects that are correlated \\'i t h t he crystall ograph ic ori e ntation of t he grain.