R. F. Decker, A. I. Rush, A. G. Dano, A. G. Freeman
A laboratory study was carried out to establish the basic causes of abnormal grain growth in air- and vacuum-melted Waspaloy, Inconel X-550, and Nimonic 80A alloys. All of the results indicated that small reduction of essentially strain-free metal were the basic cause of abnormal grain growth. Between reductions of 0.4 and 5.0 percent, in most cases, there was a narrow range of reductions responsible for abnormal growth. In a few special cases the responsible reductions were as low as 0.1 percent and as high as 9.7 percent.
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