This report presents the results of an experimental evaluation as to the effects of multi-step braze cycles and chemical milling on the mechanical properties and metallurgical constituencies of Hastelloy-X. The results show little influence on the properties of Hastelloy-X when brazed at temperatures up to 2125 degrees F. but brazing at 2150 degrees F. and 2175 degrees F. result in large grain size and reduced ductility. Rapid cooldown is necessary to obtain maximum ductility, i.e. prevent carbide precipitation in Hastelloy-X when heated to 2175 degrees F. Chemical milling has little effect on the properties of Hastelloy-X if the chem milled surface is abrasively polished to remove 0.0005 inch of chem mill affected material. This amount of material removal will prevent an increase of integranular oxidation and resulting loss in ductility of the Hastelloy-X in an air operating environment at 1600 degrees F.
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