“盐浴”冷却温度对FGH95合金组织与持久性能的影响

Influence of molten salt cooling temperatures on microstructure and stress rupture properties of FGH95 Ni-based superalloy

通过对不同工艺处理的FGH95合金进行组织形貌观察及持久性能测试,研究了"盐浴"温度对合金组织与持久性能的影响.结果表明:经1 150℃固溶及650℃盐浴冷却时和时效处理后,细小γ'相在晶内弥散析出,且少量碳化物在合金中弥散分布;随盐浴温度降低,细小γ'相尺寸逐渐减小,碳化物数量增加.当盐浴冷却温度降低到520℃,合金中细小γ'相尺寸进一步减小,且较多细小碳化物在晶内弥散析出,可改善晶内强度,使合金在实验条件下具有较长持久寿命.

By means of microstructure observation and enduring properties measurement, an investigation has been made to study the influence of the molten salt cooling temperatures on microstructure and stress rupture properties of FGH95 Ni-based superalloy. The results show that, when the alloy solution treated at 1 150℃ is quenched in molten salt at 650℃ and aged, the fine y＇ phase dispersedly precipitates in the grain, and less carbide phase distributes in the alloy. With the molten salt temperature decreases, the size of fine y＇ phase de- creases gradually, but the amount of the carbides increases. When the molten salt temperature is 520 ~C the size of fine y＇ phase decreases gradually, but the amount of the carbides increases. When the molten salt tem- perature is 520℃, the size of fine phase in the alloy decreases further, and there are more carbide particles which discontinuously precipitate in the grain and along the grain boundaries. The carbide particles are dis- persedly precipitated in the grain, which improves the grain strength and makes the alloy possess longer endur- ing life under the experimental condition.