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The nickel-base single crystal superalloys is the key material for manufacture of advanced aero-engine turbine blades , guide vanes , and continuously improve the ability of the Order of the temperature and reduce the cost of the alloy is a major research goal of the class alloy . Low Cr and high refractory (W, Mo, Nb, Ta, Re , etc.) often used to improve the order of the temperature and the ability of elements of the total alloying pathway , in particular the use of rare metals Re significantly improve the high temperature creep of the single crystal alloy and lasting performance . Typically , international single crystal alloys Re content of 3% or 6% , the alloy also increased from one generation to the second and third generation , but the cost of Re-containing single crystal alloys increased approximately an order of magnitude or more , seriously restricting the promotion of the alloy applications , development of low-cost single crystal alloy is very meaningful . In this paper, a 1% Re - containing , low-cost single crystal alloy heat treatment mainly Re - containing aggregate , gold cast structure , combined with the DSC analysis to determine the alloy solution process , discusses the solid solution impact on the distribution of alloying elements and the aging time and temperature of the γ ' size , and finally determine the optimum heat treatment process of the alloys . The results are as follows : single crystal alloy cast structure by γ, γ ' and γ / γ ' eutectic phase composition , the addition of Re did not change relative to the type of precipitation in the cast alloy , γ / γ ' eutectic shaped Maung , Re-bearing alloys dendrite is relatively small and arranged more closely solution treatment can significantly improve the segregation of alloying elements position gradually becomes smaller until all the solid solution , as the solution temperature increases , dendritic , add 1 % Re γ / γ ' eutectic solution temperature has little effect , the alloy basic solid solution after solution treatment of 1290 ° C / 4h , γ' average size of approximately 0.3 - 0.4μm aging treatment temperature of the γ 'phase morphology and size have a greater impact . Aging temperature rise was a growing trend , γ ' particles feet γ ' particles of cubic degree performance is increasing and then decreasing trend after 1290 ℃ / 4h solid solution treatment and then by 870 ° C / 96h cryogenic once aging the heat treatment process , most of the γ ' particles cubic size has significantly improved , Ah ' average size of 0.5 μm , selected as the best heat treatment process
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