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1–10 of about 1720 matches for melting methods materials
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MAINTAINING COMPETITIVENESS THROUGH TECH DEVELOPMENT (20072109)
Modern Casting V 96 N 3 P 40-44, Mar 2006 (5 p)
This article describes three research projects by the AFS Thin Wall Iron Group, Magnesium Div and Melting Methods and materials Div. that provide practical information for metalcasters to remain on the cusp of technological advancement. The goal, approach and results for each project are described. The goal of the first project was to develop dimensional data as a function of four principal green sand casting parameters. The goal of the second project was to evaluate a new high temperature magnesium alloy, AE4, with regard to bolt load retention. This alloy would be used for a magnesium engine cradle. The goal of the third project was to develop silicon recovery data when induction melting under a variety of conditions

CHOOSING THE RIGHT METALLIC RAW MATERIALS FOR IRON FOUNDRY MELTING (19670101)
AFS Transactions Vol. 75, (1967) pages 316-320 Modern Casting Vol. 52, No. 4, (October 1967) pages 88-92
The article discusses many of the raw materials available to the melter along with the advantages and limitations of each. In many respects this information is applicable to other melting methods, however, the emphasis is directed toward raw materials for cupolas and is limited to metallic raw materials. Pig Iron: (1) Blast Furnace Pig Iron which gives a high silicon level tends to produce higher levels of manganese, chromium and vanadium. (2) Primary Pig Iron - Not Blast Furnace can provide very low silicon and manganese levels important in some kinds of ductile iron production. Auto Steel Scrap: (1) Selected components, example: wheels or cut frames, are very low in phosphorus copper and chromium. (2) Bundled No. 2 Steel is not used extensively in cupolas. (3) No. 2 Automotive Slab have smaller pieces and might be cleaner than bundles. (4) Shredded or fragmented steel shows a metal analysis directly proportional to the amount of stripping prior to fragmentization. Other Steel Scrap: (1) Structural Steel from bridges have a high phosphorus level. (2) Steel punchings can be used up to 30%. (3) Electrical sheet croppings are high in silicon. (4) Foundry Steel and Cut Rails are premium material. (5) Future Cut Car Sides are relatively high in copper, Nickel and chromium because they are being made of various proprietary high strength steels. Cleaned motor blocks, Drop broken machinery cast are sources of fine scrap. Briquetted borings success is directly proportional to the condition of the briquettes. Coated material contain troublesome lead in terneplate. Galvanized steel is good but Enameled scrap cause tramp elements.

MAINTAINING COMPETITIVENESS THROUGH TECH DEVELOPMENT (20072140)
Modern Casting V 96 N 2 P 41-44, Mar 2006 (4 p)
This article details three research projects conducted by the AFS Thin Wall Iron Group, Magnesium Div, and Melting Methods and Materials Div that provide metalcasters with practical information to maintain competitiveness. The research was funded by industry, AFS and various governmental agencies. Project 1 describes an investigation into four major factors thought to influence dimensional control of gray iron castings, which in turn affects the ability to produce thin-walled gray iron castings. Project 2 describes the effort to produce a magnesium front engine cradle for the 2006 Corvette, resulting in a 35% weight savings from the current production method. Project 3 describes the melt loss, including total yield and alloy loss under various induction melting conditions.

MAINTAINING COMPETITIVENESS THROUGH TECH DEVELOPMENT (20072087)
Modern Casting V 96 N 3 P 40-44, Mar 2006 (5 p)
This article describes three AFS research projects that provide practical information for metalcasters to remain on the cusp of technological advancement. These general description of these projects are (1) dimensional tolerance challenge, (2) magnesium in automotive applications and (3) melting methods and materials. The first project was designed to provide dimensional capability information of iron castings. The second project investigated the creep resistance of a magnesium alloy, AE4. The alloy was evaluated by bolt load retention testing. Corrosion resistance was also evaluated. A magnesium engine cradle for the ZO6 Corvette was successfully produced in this alloy. The final project described in the article evaluated silicon recovery under a variety of induction melting conditions.

SPECIALTY MELTING AS A SERVICE FUNCTION IN A RESEARCH LABORATORY (3219)
Transactions of the American Foundrymen's Society V 69 P 483-493, 1961 (11 p)
Equipment for vacuum induction melting, consumable and inert electrode arc melting, atomic hydrogen melting and zone melting both horizontally and by the floating zone method are described. Applications of this equipment in the performance of service melting of a wide variety of specialty materials for use in a research laboratory is discussed. In this discussion methods are brought out for determining which of the many types of raw materials, crucibles and melting practices is most suitable to the particular job.

CAST IRON STRUCTURE AND PROPERTIES (3290)
Transactions of the American Foundrymen's Society V 70 P 176-186, 1962 (11 p)
By comparison with other materials, the range of properties of cast iron is unusually wide. It extends from chilled cast iron to gray iron and spheroidal graphite cast iron. In contrast to many other alloy systems, we are still in the dark regarding the relationship between chemical composition, structure and properties of cast iron. It can be shown that about 20 factors may influence its properties. Assuming linear relations, which cannot always be expected between factors of influence and target values, it would be necessary to carry out at least 22" experiments (or more than one million) in order to obtain a clear picture. By sorting out some of the influencing factors, one arrives at three complexes which facilitate the approach to putting the questions: 1. T h e actual alloying elements in cast iron can satisfactorily be comprehended by the "degree of normality" (or by the carbon equivalent). 2. T h e influence of the rate of cooling can be controlled by standardizing the test pieces and the molding material. 3. T h e third group of factors can be represented by the conditions of nuclei formation and of crystallization, which are governed by the time-temperature curve of the melting process and by the distribution of certain trace elements. This third group exerts a much stronger effect than is commonly believed. A broad field of scatter will be observed when plotting tensile values (obtained in ordinary foundry practice) against carbon equivalent or degree of normality- This scatter cannot be explained as a result of changes in the quantity ratio among the: elements themselves which are accompanying the iron. This influence is obviously small and the scatter can only derive from changes in the melting process and in the selection of rawmaterials. The scatter of values obtained in normal practice could be imitated by using iron charges which had been prepared from a varietv of pig iron grades and melted under conditions of a defined time-temperature inoculation program. At the same time the eutectic cells became coarser and the graphite in the cell branched out much more. This resulted in decreasing quantities of A graphite and increasing quantities of D graphite. When, after superheating, the melt was allowed to stand, the property values began to aller in the opposite direction, and this became more pronounced after inoculating the melt with ferrosilicon. Inoculation with calcium silicide resulted in the highest degree of normality, coupled with the smallest eutectic cells, 100 per cent A graphite and no D graphite. Distinct differences in the level of these values could be observed among the various pig iron grades used, and differences were still well recognizable when synthetic melts, having small additions of pig iron, were melted or when charges with scrap additions were melted in ordinary foundry practice. Evaluation of these results for practical cupola operation will increase, the degree of accuracy aimed at in the production of cast iron.

USE OF EPOXY RESIN AS PATTERN MATERIAL (2766)
Transactions of the American Foundrymen's Society V 64 P 504-508, 1956 (5 p)
The Pattern Shop and the Materials Laboratory at the Puget Sound Naval Shipyard are now conducting a series of tests to develop and manufacture plastic foundry patterns that will justify their use both economically and technically. They do have their limitations, but when these are recognized and corrective measures taken in the manufacturing processes these limitations can well be overcome, thereby making some of the epoxy resins excellent pattern materials. Several methods have been developed to success fully cast the various types of patterns and coreboxes.

EFFECTS OF GATING PRACTICE ON LEAK TIGHTNESS OF 85-5-5-5 AND 81-3-7-9 ALLOY CASTINGS (2244)
Transactions of the American Foundrymen's Society V 60 P 287-295, 1952 (9 p)
Foundrymen will universally agree that gating practice is an important aspect of foundry operation. There is, however, no universal agreement regarding the best method which should be employed to gate the castings. Recent studies 1< * sponsored by the American Foundrymen's Society have shown that turbulence and air aspiration must be carefully avoided if sound castings of reactive metals are to be produced. On the basis of this work, it appeared that it would be more desirable to gate experimental leak-test cast ings at the bottom in order to avoid the turbulence which would occur if the melt was introduced at the top of the mold cavity. This, however, differed from some commercial practices. Accordingly, an investi gation was undertaken to compare the effects of gating practice on the leak tightness of 85-5-5-5 and 81-3-7-9 alloys. Incidentally, the effects of pouring temperature and melting practice were also determined, and a comparison was made of the relative susceptibilities of the two alloys, 85-5-5-5 and 81-3-7-9, to leakage. This paper describes the results obtained in this in vestigation.

SOME FACTORS AFFECTING SPHERICAL TYPE MACRO-GAS POROSITY IN 85-5-5-5 BRONZE (2343)
Transactions of the American Foundrymen's Society V 61 P 327-346, 1953 (20 p)
The effect of mold materials, binders and coatings on the liberation of gas in S5-5-5-5 bronze when poured into dry sand mold cavities was investigated. Melting methods, degassifying and deoxidizing practices were also studied. The observations were made on a specially designed casting and the results recorded by photograph. More than 250 test castings have been examined. Spherical type macro-gas porosity has been observed on 85-5-5-5 bronze poured into oil bonded silica sand molds. Gassing is the result of a metal-mold reaction or direct absorption of gas which is liberated upon solidification of the metal. Many commercial sand binders were tested. Ounce metal poured in pitch-bonded molds showed no spherical type macroporosity. Cement bonded and natural sand molds produced castings practically free of the macro-gas porosity. Molds made with phenolic, urea, wood resins, etc., gassed ounce metal to various degrees of intensity. Graphite coatings containing pitch and a special coating containing zircon filler in a resin-volatile solvent vehicle inhibited or reduced the gas porosity. These coatings gave poorer casting surfaces. Lithium was found to be an effective degassifier but was characterized by higher metal shrinkage. Deoxidizers were tested and their relation to shrinkage is shown on a special test cast ing. Metal composition also influences macro gas-porosity.

PRECISION CASTING MOLD MATERIALS (3120)
Transactions of the American Foundrymen's Society V 68 P 455-464, 1960 (10 p)
Various types of inorganic binders are discussed with particular emphasis on their chemical formation and high temperature properties. Differential thermal analysis is valuable in the determination of baking temperature required to eliminate refractory composition gaseous products. Mold dimensional stability is determined, for the most part, by aggregate characteristics, with some contribution from the binder (which depends on the original mix bond and liquid percentage).

1–10 of about 1720 matches for melting methods materials
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