Characteristics of Phenolic-Urethane Cold Box Sand Cores for Aluminum Casting
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This work presents the results of a series of tests carried out on mixtures of sand and binders used in phenolic-urethane cold box cores. Two resin binders and silica sand with two grain size distributions were analyzed; the cores were blown with blends of sand that had resins within the range of 0.8 to 1.15%. The mechanical properties of the mixtures were obtained by blowing them into conventional tension test specimens. The strength of the material was recorded at room temperature and at 70C and 150C (158F and 302F). A gas evolution chamber was used to measure the amount of gas that is produced when the mixture of sand and resin is burned. These measurements were carried out on fresh samples that were heated for 30 or 60 minutes at either 70C or 150C (158F and 302F) prior to burning. This study was carried out to determine which resin fulfills the conditions critical to obtaining sound aluminum castings.
Keywordscasting binders aluminum sand cores cold box
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- 2.Campbell, J., Castings, 2nd Ed., Butterworth-Heinemann, Oxford (2003).Google Scholar
- 3.Gundlach, R.B., Ross, B., Hetke, A., Valtierra, S., and Mojica, J.F., “Thermal Fatigue Resistance of Hypoeutectic Aluminum-Silicon Casting Alloys”, Transactions of the American Foundrymen’s Society, vol. 102, pp. 205–223 (1994).Google Scholar
- 5.Wile, L.E., Strausbaugh, K., Archibald, J.J., Smith, R.L. and Piwonka, T.S., “Coremaking”, ASM Handbook, Casting, vol. 15, p. 238, ASM International, Materials Park, OH (1988).Google Scholar
- 6.Archibald, J.J. and Smith, R.L. “Resin Binder Processes,” ASM Handbook, Casting, vol. 15, p. 214, ASM International, Materials Park, OH (1988).Google Scholar
- 7.Brown, J.R., Foseco Ferrous Foundryman’s Handbook, Butterworth-Heinemann, Oxford (2000).Google Scholar
- 8.Locke, C., and Ashbrook, R.L., “Nature of Mold Cavity Gases”, Transactions of the American Foundrymen’s Society, vol. 58, pp. 584–594 (1950).Google Scholar
- 10.Dietert, H.W. Foundry Core Practice, 3rd Ed. American Foundrymen’s Society, Des Plaines, IL (1966).Google Scholar
- 11.Winardi, L., Littleton, H., and Bates, C.E., “New Technique for Measuring Permeability of Cores Made from Various Sands, Binders, Additives and Coatings,” Transactions of the American Foundry Society, vol. 113, pp. 393–406 (2005).Google Scholar
- 12.Naro, R.L. and Pelfrey, R.L. “Gas Evolution of Synthetic Core Binders: Relationship to Casting Blowhole Defects,” Transactions of the American Foundrymen’s Society, vol. 91, pp. 365–376 (1983).Google Scholar
- 13.Velasco, E., Rodríguez, A., González, J.A., Talamantes, J., Colás, R., and Valtierra, S., “Use of Microscopical Techniques in Failure Analysis and Defect Control in Automotive Castings,” Microscopy and Microanalysis, vol. 9 (Suppl. 2), p. 160 (2003).Google Scholar
- 14.W.H. Moore, R.K. Lenhart and Y. Julin, “Effect of Heat on Chemical Binders”, Transactions of the American Foundrymen’s Society, vol. 96, pp. 903–912 (1988).Google Scholar