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REPAIR BY WELDING OF CAST COPPER ALLOYS 69-47 (19690853)
AFS Transactions 1969, p. 198-204 Modern Casting (Oct. 1969),
The feasibility of repair welding of copper alloy castings is considered from the standpoints of economy and practicality. Welding processes are discussed and the preferred method of welding determined as being either of the 2 inert-gas shielded arc processes. Copper casting alloys are divided into 6 classes based on major alloying elements. These classes are silicon bronze, aluminum bronze, tin, bronze, and gunmetals, brasses, cupro-nickel and nickel silver. Some classes are further divided into subgroups which relate to the metallurgical structure and have important effects on weldability. The author discusses his own experience with the welding of tin bronze and gunmetal alloys and the development of a filler wire that deposited pore-free welds of good strength using the metal inert-gas process. The welding of other classes of alloys is reported on the basis of research conducted by leading authorities in several countries, including a unique development by Russian researchers. It is concluded that repair by welding of copper alloy castings is economically feasible depending upon the nature of the alloys, the design of the casting and the condition of the metal in the repair area.

THERMAL BEHAVIOR OF METALLIC MOLDS WITH LONG FREEZING RANGE ALLOYS (3508)
Transactions of the American Foundrymen's Society V 72 P 65-72, 1964 (8 p)
The thermal behavior of cast iron and anodized aluminum molds during solidification of aluminum- 4.5 per cent copper and aluminum-10 per cent magnesium, long freezing range alloy, test castings have been studied. It is found that: a) For the casting and mold wall thickness considered (1) test castings solidify akin to a skin forming alloy, (2) the solidification constant increases with the increase in the mold wall thickness and (3) solidification time of test castings is approximately proportional to square of volume/surface area ratio. b) In general, start of air gap formation takes place earlier in cast iron mold compared to anodized aluminum. c) The maximum interface temperature attained in a just and over sufficient mold is dependent upon (1) start of air gap formation, and (2) percentage of solids formed prior to air gap formation. d) The maximum interface temperature attained in an under sufficient mold is primarily influenced by the start of air gap formation time. e) Heat capacity effect on the interface temperature is reflected upon only at later stages of freezing.

MICROSEGREGATION IN CASTINGS AND INGOTS (3537)
Transactions of the American Foundrymen's Society V 72 P 353-362, 1964 (10 p)
Recent research on microsegregation in castings and ingots at Massachusetts Institute of Technology is summarized. It is shown that simple mathematics are adequate to approximately predict the severity of segregation, as measured by segregation ratio (ratio of maximum to minimum composition over distances the order of dendrite arm spacings). The major source of error in the simple analysis is that it neglects diffusion in the solid during freezing. More detailed analyses which take this diffusion into consideration agree quantitatively with experiment. Also in agreement with experiment, segregation ratio is shown to be nearly independent of rate of solidification over a wide range of rates of solidification, even when diffusion in the solid is an important factor. Dendrite morphology is briefly discussed because of its influence on the form of microsegregates; at least in the latter stages of solidification, dendrites prefer a platelike morphology. Homogenization of castings is considered in the light of the foregoing and it is shown to be extremely difficult, in all but rapidly solidified castings to achieve complete homogenization. Sample calculations are given for low alloy steel. It is shown, for example, that a low alloy steel casting solidified at moderate rate requires at least one hr at temperatures in excess of 2500 F (or much longer times at slightly lower temperatures) to achieve significant homogenization of elements other than carbon. Considerable difficulty is also experienced in obtaining fully homogeneous wrought material, because of dendritic segregation in the original ingot. Mechanical properties of both ferrous and nonferrous castingg are substantially improved by intensive homogenization treatments.

TECHNIQUES FOR IMPROVING STRENGTH AND DUCTILITY OF ALUMINUM ALLOY CASTINGS (2424)
Transactions of the American Foundrymen's Society V 62 P 219-230, 1954 (12 p)
This paper discusses principles and variables involved in making high strength aluminum alloy castings, as well as practical means for controlling factors necessary for obtaining maximum available strength from them. With the necessary conditions attained, mechanical properties equivalent to those of corresponding wrought aluminum alloys can be achieved. Detailed description is give?x of a reduced pressure test proposed by Baker, in England, for indicating gas content of molten aluminum, and evidence of the great value of this test as a quality control tool is presented.

FLUIDITY OF ALUMINUM (3381)
Transactions of the American Foundrymen's Society V 70 P 1029-1039, 1962 (11 p)
Research conducted in the course of a 3 1/2-year fundamental research program on fluidity of aluminum alloys is briefly summarized. Detailed results are reported of work conducted on (1) effects of surface tension and vibration on the ability of metal to enter small diameter holes (0.02 to 0.20 in. diameter) and (2) effects of heat losses in gating systems on fluidity. Vibration is shown to be an effective method of increasing the ability of metal to enter small diameter channels (less than 0.10 in. diameter); it has relatively little effect in larger test channels. Vibration must be applied in such a way that it increases effective metal head. Calculation and experiment indicate that temperature losses in gating systems are generally negligible in practice.

SOME EFFECTS OF COPPER ADDITIONS TO PEARLITIC MALLEABLE IRON (3462)
Transactions of the American Foundrymen's Society V 71 P 477-480, 1963 (4 p)
The effects of copper additions on the mechanical properties of pearlitic malleable have been investigated for both air quenched and liquid quenched grades. A range of copper contents from about 0.5 per cent to about 1.5 per cent was investigated. It was found that addition of copper up to about one per cent produced a distinct improvement in mechanical properties in air quenched pearlitic malleable. This improvement appeared to be the result of an increase in hardenability. It was found that still further improvement in mechanical properties could be obtained by age hardening. Further investigation of copper alloyed pearlitic, especially for possible production of high strength air quenched material, appears warranted.

MARINE CORROSION OF A WHITE COPPER-BASE ALLOY WITH ZINC, MANGANESE, NICKEL AND ALUMINUM (19740255)
AFS Transactions 1973, p. 471-474
A study was made to learn the corrosion resistance in sea water of a white copper-base alloy with zinc, manganese, nickel and aluminum toward potential use in marine castings for sea water service including propellers. These tests show that this new alloy family behaved similar to manganese bronze in short term velocity tests. Nickel aluminum bronze had better velocity corrosion resistance than any of the alloys tested. In the quiet sea water testing program, the regular low aluminum formula (Alloy A) displayed the best overall corrosion resistance. The manganese bronze alloy showed dezincification and the nickel aluminum bronze alloy suffered widespread pitting and crevice corrosion.

TRENDS IN ALUMINUM CASTING ALLOYS (2084)
Transactions of the American Foundrymen's Society V 58 P 69-75, 1950
Casting alloys of aluminum are used in ever increasing amounts. This increase is due to several factors. With time the structural and economic value of this metal has been more and more recognized, and more engineers and foundrymen have become acquainted with the metal. But also, the introduction of newer alloys and the evolution which older alloys have gone through made the metal easier to handle iti the foundry. The expansion of the use of aluminum in die casting is a typical example. Aluminum alloys are cast mainly in sand, permanent mold and die cast ing, but increasing quantities are being consumed by other casting processes such as plaster molding, centrifugal and investment molding. Early American alloys were like the European, the aluminum-zinc-copper alloys. However, since these alloys are inherently hot short they soon lost their standing in favor of the aluminum-copper alloys.

HIGH STRENGTH YELLOW BRASS CASTINGS WELD REPAIR (3221)
Transactions of the American Foundrymen's Society V 69 P 497-503, 1961 (7 p)
An investigation was conducted on the repair welding of high strength yellow brass castings. Test castings oxyacetylene gas and inert-gas-shielded-arc welded with several types of fillers were evaluated. Tensile and bend tests on samples removed from these castings showed that satisfactory high strength, high ductility welds could be obtained by inert-gas-shielded-arc welding with base metal composition filler and high manganese aluminum bronze alloy filler. Several production castings welded in this manner supported the experimental results. Additional information is presented on microhardness tests and metallographic interpretation of the weld deposits.

EFFECT OF TITANIUM ON GRAIN SIZE AND TENSILE PROPERTIES OF AN ALUMINUM-4.5 PER CENT COPPER (NO. 195) CASTING ALLOY (1998)
Transactions of the American Foundrymen's Society V 56 P 398-408, 1948 (11 p)

1–10 of about 2000 matches for copper alloy
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