Characteristics of Phenolic-Urethane Cold Box Sand Cores for Aluminum Casting
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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