Abstract: Chromium-base alloys, which have been under study now for slightly more than two decades, are attractive as potential competitors with nickel alloys for high temperature applications in advanced jet engines. Although chromium has a strength-to-density advantage over nickel, it is normally brittle at room temperature and is further embrittled by nitrogen during high temperature air exposure.

Abstract: Two innovations in the extractive metallurgy of nickel are described. One is the introduction of the top blown rotary converter (TBRC) to the nonferrous smelting industry for iron slagging and metal making. The other is the application of the Inco Pressure Carbonyl (IPC) process to a wide variety of metallurgical feed materials for the recovery of pure nickel, cobalt and iron.

Abstract: Mar-M alloy 509 is a contemporary Co-base alloy intended for constructional use in a corrosive environment at high temperature. This paper is the result of a continuing investigation to evaluate mechanical, process and physical parameters of this alloy system. The alloy exhibits low room-temperature ductility; heat treatments can improve ductility but will reduce rupture life at moderate stress and temperature (25ksi, 1600°F.) Mar-M alloy 509 exhibits good oxidation resistance to 1900°F and excellent hot-corrosion resistance at 1600°F. The flat negative slope of the Mar-M alloy 509 stress-rupture curve also indicates a high degree of phase stability.

Abstract: Our discussion has covered a great deal of ground and that in rather cursory fashion, but it is hoped that it will serve as an introduction to the subject which will aid the interested reader in the assimilation and assessment of the very large number of papers available in the literature. The basics of the behavior of pores, both voids and bubbles, in solids, with and without driving forces, appear to be well-established. Quantitative agreement between theory and experiment has been obtained in several instances, all involving a dominant driving force, either curvature or thermal gradient. On the other hand, when no driving forces exist, the restraining effects of structural defects must be carefully considered in any “random-walk” analysis. Also, the effects of faceting of pores due to anisotropy of surface tension become very important. Further effects of possible significance include strain field interactions between pores or between pores and surfaces. In short, when no driving force is applied, many normally small effects take on great importance and are extremely elusive of quantitative analysis. On the other hand, the presence of a strong driving force may well “swamp out” these effects and thus provide results in agreement with predictions of an idealized theory.

Abstract: High-purity alloys of cobalt and rare-earth metals were produced by electrodeposition of rare-earth metal on a consumable cobalt cathode. These alloys, rich in rare-earth metals, are suitable for the preparation of cobalt-rare-earth compounds with addition of more cobalt by melting. The compounds can then be made into fine-particle permanent magnets by pulverization and consolidation.

Abstract: This list is by no means exhaustive. However, it does illustrate that metals play a vital role in diverse areas of restorative surgery14 The recent comment by Laing15 seems to sum up the theme of this introductory article: “The surgeon waits at the door of the materials laboratory for the tools of his trade… usually this is the door of the metallurgical laboratory.”

Abstract: Previous studies showed that Ni3Cb precipitation behavior appears to follow a predictable pattern with increased strain in the precipitation range for this phase. Additional investigation was initiated in order to further the understanding of Ni3Cb precipitation under similar strain conditions and to develop some information on the effects of such conditions on the stability of gamma prime and the formation of sigma or other phases often considered detrimental to performance. Samples from a production heat were treated above the Ni3Cb precipitation range and subsequently strained between 0% RA and 35% RA at 1500°F. Light and electron microscopy and X-ray diffraction studies were performed on samples in the as-strained condition; after a 1750°F gamma prime solution treatment; after a 1750°F treatment followed by a double aging, gamma prime precipitation treatment and after a fully aged plus 1250°F-500 hour exposure. It was found that the quantity of Ni3Cb which precipitated during the 1750°F treatment step increases markedly with the degree of strain, that gamma prime stability is not significantly affected by strain or the quantity of Ni3Cb precipitate, and that sigma and similar phases do not form during prolonged exposure at the upper end of the useful temperature range for this alloy, even at the highest strain level investigated.

Abstract: Uniform, fine grain size is generally preferred in forgings of Alloy 718 for optimum properties. However, due to limitations imposed by forging equipment, forging size and forging configuration, it is often impossible to produce this desired grain size; instead, some grain duplexing or grain coarsening occurs in certain areas throughout the forging. Stress-rupture tests were conducted before exposure, and after exposing specimens at 1250°F, 50 ksi or 1300°F, 50 ksi for 500 hrs. on material having (1) uniform fine grain size (ASTM 7 or finer), (2) duplex grain size, and (3) uniform coarse grain size (ASTM 5 or coarser). These grain sizes were obtained in forgings with a simple pansake configuration using varying forging techniques. The results of the rupture tests conducted before exposure showed an excellent correlation with grain size and Ni3Cb plate size. After exposure, rupture ductility increased and strength decreased due to overaging. In duplexed samples the controlling factor appears to be the amount and size of the coarse grain. The optimum grain size for the best balance of rupture properties appears to be ASTM 6–7.

Abstract: The oxygen converting test work, Tables VI and VII, provided sufficiently favorable and reproducible results to warrant installation of necessary facilities for commercial use of the process at the Utah smelter. All nine converters on the aisle were modified to permit enrichment of the blast air with oxygen and to provide for pneumatic feeding of concentrate and precipitate. The smelter material handling system was expanded to allow direct delivery of the moist material to 80 ton feed bins at each converter. An on-site oxygen, plant was constructed by the Linde Division, Union Carbide Corp., near the smelter plant; a high proportion of the oxygen will be directly delivered to the smelter for use in the oxygen converting process.

Abstract: The Hazelett Strip-Casting has the attractive advantage of rapid change of slab width and thickness. It was demonstrated during our program that width was easier to change than thickness.

Abstract: Temperature and movements occurring in the cathode of a reduction furnace were explored by constructing and operating for short periods a number of 10 KA cells or “one-bar furnaces”. Each furnace consisted essentially of a slice across a high amperage industrial furnace and thus contained one cathode bar together with its carbon block (or blocks) and its attendant rammed-carbon side-lining, brickwork, etc. The steel box was specially designed to permit the conditions obtained in a large furnace to be simulated, and also to enable the restraints on expansion to be varied experimentally. Temperatures and outward movements of cathode block and box sections, and arching of the cathode bar, were measured during preheating, starting, and operation.

Abstract: In this survey we have shown that among most of the additions of potential interest, LiF and NaCl are the only substances which increase the specific conductivity of cryolite-alumina melts. However, it should be mentioned that beside the substance which increases the specific conductivity of the cryolite melts directly, there are others which in the technical process appear to increase the conductivity of the electrolyte indirectly, e.g. by improving the separation of the carbon particles from the electrolyte as does MgF2. Furthermore, it must be stressed that the experimental results which have been discussed in the previous chapter were obtained under ideal conditions for pure molten salt mixtures. Therefore, they cannot be utilized directly on the conditions in the technical process. For the study of the influence of various additions on the electrical conductivity under industrial conditions the interactions between the electrodes and the electrolyte,4,84 the general influence of the carbon particles which are present in the electrolyte in the form of “carbon froth”,35,30 as well as the influence of the dissolved metal37–42 on conductivities must be considered.

Abstract: Historical background to and present state of the slag fuming plant at the Boliden Smelter is being reported. Technical and metallurgical operating data are revealed and future possibilities for automatic process control and integration of ore dressing, smelting, fuming, and deleading operations are indicated.

Abstract: This paper describes the results of studies to improve the effectiveness of Na2SO4 for removing copper from molten iron. These studies included the use of sulfate mixtures, recycling of used slags, and additions of Na2SO4 in lump form versus powder. The results can be summarized as follows

Abstract: Filter residues are mixed in high proportion with pyrite cinders and subjected to a modified chloridizing and sulfatizing roast in standard multiple-hearth furnaces. By additions of sodium chloride and of suitable sulfur-bearing materials, the metals Cu, Zn, and Cd, as well as Ag and Au, are rendered soluble to a large extent. By leaching with acid, Zn, Cu, Ag, Cd, and Au are eluted. The remaining iron oxide is conveyed into sintering or pelletizing plants.

Abstract: With a precise calculation of the different materials to be charged into the converter, the steelmaker is able to increase noticeably the regularity of his metallurgical operations.

Abstract: The first continuous casting plant of Nippon Kokan was commissioned on March 23, 1967, at the Plate Dept. of Keihin Works. The one-strand machine is of curcular type for casting a slab of 200 × 1600 mm2, which was planned and constructed by Demag-Stranggiess-Technik and Hitachi Shipbuilding Ltd., with the operational know-how of Mannessmann A. G. The nominal capacity of this machine is 20,000 tons/M. This capacity was reached within six months after beginning operation and in December 1968, 40435 ton/M. was cast without any breakout from the start. A monthly production of over 40,000 tons can be maintained in the future. These results are due to complete mastering of the continuous casting technique and to various technical developments and research which is still being conducted by the steel shop and the Research Center.

Abstract: Results obtained with our experimental 5-tph shallow-bath reactor, or forehearth, demonstrated that continuous steelmaking by the progressive oxygen lancing of a hot metal stream is technically feasible. Carbon, silicon, manganese, phosphorus, and sulfur are removed as a function of distance along the furnace, and metal composition and temperature gradients are well defined. Ease of access to the bath permits rapid measurement of metal carbon and temperature with frequency required for process control. By controlling input variables and end-point temperature, steels have been produced with carbon concentrations ranging from the 0.03 to 1.10%. Product sulfur and phosphorus concentrations of less than 0.02 and 0.01%, respectively, have been attained. The cost of metallics, fluxes, and oxygen per net ton of product is comparable to that of other modern oxygen steelmaking processes. Although the technical feasibility of the process with parallel slag-metal flow has been demonstrated, more extensive testing on a larger scale would be required before it could be considered for commercialization. For example, experimental difficulties were encountered in maintaining steady carbon in the product and in utilizing ore efficiently in the process. Hot metal input to the small forehearth could not be controlled closer than ±10% of the target rate of five tons per hour, and consequently the variation in product carbon ranged from ±0.03 to ±0.12% C. In the runs where control of bath temperature was attempted, only about 35% of the ore was accounted for in the bath, the balance remaining in the slag. In addition to efficient utilization of iron and oxygen units from iron ore, the process economics would require the development of materials or techniques to extend refractory life. Use of prepared scrap as a coolant instead of iron ore would increase the versatility of the process. Also, counter slag-metal flow2,8 might be used to advantage for lowering residual sulfur and phosphorus and for increasing product yield.

Abstract: A method was developed in which beryllium metal was electrowon from BeO in a 60 mole % LiF-40 mole % BeF2 electrolyte at an applied voltage of 2.6 v and a temperature of 700°C. After electrolysis, the metal product and salt were briefly heated at 1300°C to coalesce the beryllium into spheres, then cooled to 900°C and poured through a stainless steel screen for recovery of the metal.

Abstract: Scanning electron microscopy has shown that in the aluminium/silicon and iron/graphite eutectic systems the non-metal is interconnected throughout each eutectic cell, that is, for each initial nucleation event.

Abstract: Uranium metal was prepared by reacting an oxide (UO2 or U3O8) with graphite powder under vacuum conditions. U3O8 prepared from production grade UO3 gave the highest uranium content per unit volume of charge compared to other uranium oxide sources.

Abstract: It is now almost a decade since the introduction of massive federal support to universities for graduate education and research in the materials field. Accordingly, it is appropriate to examine the changes in the nature and activity of the field which have occurred during this period, both in the universities themselves, and in professional practice in industry and government, and also the implications of such changes for graduate education in metallurgy and materials science in the future.