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Transactions of the American Foundrymen's Society V 63 P 687-688, 1955 (2 p)
We have cut cleaning room labor by approximately 5 man-hours per ton and percentage defective by a little more than 20 per cent by furnishing cleaner steel castings to the cleaning room. This has been done through the concerted effort of all departments of the foundry. To begin with, the heads of all departments meet daily to interpret production and cost factors from the casting blueprint.

AFS TRANSACTIONS 1970, p. 338-342
This study has demonstrated that decarburization associated with the casting of steel into the Avnet-Shaw process molds can be related to the mold temperature and the casting cooling rate. Decarburization can be completely eliminated by flushing all O2 from the mold and replacing it with high purity Ar. Hexamethylene tetramine (HMT), (CH2)6N4 additions are not effective in eliminating decarburization but rather recarburize the steel surface after a given amount of decarburization has occurred. The effective use of HMT is highly process sensitive since it may result in a decarburized zone beneath the casting surface. Certain mold additions were found to be effective in reducing or eliminating decarburization of 8620 or 52100 steel. Carbon additions reduced decarburization but their effect depended upon the particle size of the addition--the optimum size being about 100 mesh. Of a series of deoxidizers studied, ferroboron and ferromanganese additions (2%) were found to essentially eliminate decarburization in the 52100 steel. Additions of Ti, Mg-bearing ferro-silicon, Si- Mn and ferrovanadium were also effective in reducing the amount of decarburization in 8620 and 52100 steels.

AFS TRANSACTIONS (1970), p. 293-296
The system of gating sand castings using fluid flow criteria developed by AFS for gray iron has been simplified and reduced to a single equation. The hypothesis that this equation can be used to calculate the gating system for any alloy with the correct choice of X and K was tested by several experiments. A computer program was written to quickly and accurately calculate choke areas from the necessary input. Concurrently, the surface area to volume ratio approach to the risering of stainless steel was investigated. Work of other authors was collected and a graph of riser size (dia equals height) vs surface area and volume was generated using metal shrinkage and mold wall movement data from the literature. Using the AFS gating equation with X=0.279 lb/in. and K=0.4 and the risering graph mentioned above, trials were run in HL-40 stainless steel. Three sizes of high temperature support brackets were successfully cast; one separately, the other 2 back to back from a common gating system. The system was adopted by the production foundry. Pictures and diagrams of the gating systems used and the proper values of fluidity and density, the AFS gating equation for gray iron can be applied to stainless steel with success; riser sizes for stainless castings in green sand can be determined by using a surface area to volume ratio-technique with proper values of total shrinkage during solidification inserted in the defining equation.

Transactions of the American Foundrymen's Society V 70 P 654-658, 1962 (5 p)
With increased use of the Charpy test for specification and for material selection, misinterpretation of the test and overrating of its value has occurred. This paper examines the Charpy test critically, and by indicating the behavior of different steels under each of the embrittling factors of the Charpy test, it limits the interpretation of the test and the possible uses of the test.

Framework for a Comparative Life Cycle Assessment of Magnesium and Steel Autoparts (20082878)
Proceedings of the Third International Conference on Light Metals Technology Sept 24-26 2007 Quebec, Canada P243-248
The physical properties of magnesium alloys can be exploited for substituting carbon steel components in cars for a subsequent reduction in fuel consumption and tailpipe emissions, while maintaining the same safety performance. A collaborative life cycle assessment (LCA) between Canada-USA in partnership with Australia is being undertaken for the “Magnesium Front End Research and Development” project. Energy use and potential environmental impacts of using magnesium alloys are assessed in relation to conventional carbon steel front-end parts used in a North America (NA) build luxury vehicle driven for 200,000 km in NA. The scope of this cradle-to-cradle LCA study is limited to NA with the exception of the production of magnesium ingots that is occurring in China. Preliminary LCA results indicate the importance of a wider availability of magnesium life cycle inventory data and demonstrate the fundamental importance of the “end-of-life” recycling of magnesium in order to realize the full benefits of lightweight materials.

Stainless Steel Thrives on Tough Product Applications (20082688)
Modern Metals V38 N2 P47-51
Several recent applications of stainless steel including explosive containers, fuel rod control elements, auto exhaust manifolds and keyless entry systems are described. Each part/component is discussed and the advantages that resulted from switching to a stainless steel alloy are considered. Reported benefits include increased strength, weigh reduction, extended durability and corrosion resistance. Alloys being utilized in new applications include Armco’s Nitronic 50 and 305, 309 and 310 stainless.

Transactions of the American Foundrymen's Society V 68 P 756-764, 1960 (9 p)
The rapid rise of basic oxygen steelmaking in the wrought steel industry has led to an analysis of its possible future in the steel foundry. While this process has made a wide range of carbon and low-alloy wrought steels, it has not yet been used for steel castings. Operating, metallurgical and estimated cost comparisons have been made for a basic cupola oxygen furnace shop vs. an arc furnace installation. Here, costs, operating and metallurgical flexibility are in favor of the arc furnace, but an oxygen furnace installation may offer interesting possibilities. Of necessity, this study was limited, so that further analyses on a specific basis is indicated. The final answers as to the practicality of oxygen steelmaking for castings remains with the steel foundry operators.

Effect of High Thermal Conductivity Die Steel in Aluminum Casting (20082950)
International Journal of Metalcasting V2 I2 P47-55
Recently, the application of aluminum die cast parts in automobile manufacturing has increased because of the greater demand for automotive weight reduction. For even wider application, it is necessary to reduce manufacturing costs and improve product quality. A material possessing a thermal conductivity 50% higher than the conventional 5% chromium hot work tool steel, AISI-H13, was developed as a die material for high and low pressure die casting machines.

AFS Transactions 1971 p. 25-30
A new cast maraging stainless steel composition strengthened with silicon was developed. Nominal composition is 9% Ni--11.5% Cr--2.0% Si--0.05% Al--0.05% Ti. The alloy is heat treated by solution annealing one hour at 1900 F (1038 C) and maraging 3 hours at 850 F (454.4C) Nominal yield strength of the alloy is 155 ksi, Charpy V-Notch impact strength is 50 ft-lb. Atmospheric corrosion resistance is superior to Type 410 stainless steel. The alloy can be air melted. Fluidity, pattern shrinkage, casting soundness and freedom from segregation in heats up to 200 lb all appeared satisfactory. Each heat was cast into two dry sand molds: a double keel block. Each leg of the keel block measured one in/by seven in. by 1/12/ in. high. A larger casting was poured as a single keel block whose leg measured 2 x 13 1/4 x 8 3/4 in. high. All heats were poured at 2850 F (1565.6C). Alloys with lower nickel-plus-chromium contents had much poorer toughness. Alloys containing 8-10% ni and 10-12% Cr, on the other hand, had quite good properties. These alloys typically had yield strengths on the order of 150 ski and Charpy impact energy values of 56 ft-lb. It is noteworthy that while the lower silicon contents gave lower strengths, on the order of 130 ski, the Charpy Impact energy values were on the order of 100 ft-lb.

Transactions of the American Foundrymen's Society V 71 P 783-790, 1963 (8 p)
This progress report summarizes the significant data which have been obtained concerning the (1) nature, (2) causes and (3) means of prevention of macroinclusions in steel castings. Based on this summary, new techniques for research are proposed and illustrated. 1. In aluminum killed green sand castings it has been shown that typical macroinclusions are composed of corundum (A1203) and a silicate glass. In some cases of high F e d content the corundum is altered to hercynite (FeOAl203). 2. Inclusions of this type can originate from four sources: a) During deoxidation with aluminum in the ladle. b) Reaction of Al with the ladle refractories. c) Reaction of Al and other elements in the steel with air and mold gases during pouring. d) Reaction of the steel with mold materials. The volume of the inclusions can be increased by agglomeration with loose sand of the mold. 3. Several means of prevention have been tried. The addition of fluxes such as calcium fluoride with the hope of causing the inclusions to seep into the mold wall resulted in unsatisfactory casting surfaces. The control of metal flow, using a whirl gate as an inclusion trap has been successful in some cases. New techniques are proposed to evaluate more definitely the causes of macroinclusions. These include a melting furnace with vacuum or controlled atmosphere in which inclusions can be generated under controlled conditions and collected for examination. With a satisfactory basic investigation of the kinetics of inclusion formation, better remedial measures should develop.

1–10 of about 6180 matches for steel
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