固溶处理对GH4700镍基合金管组织及力学性能的影响

Effect of Solid Solution Treatment on Structure and Mechanical Properties of Nickel Base Alloy GH4700

研究了1 000～1 150℃固溶处理对GH4700合金(/%:0.05C、25Cr、20Co、1.65Nb、1.47Al、1.69Ti,余Ni)组织及力学性能的影响:结果表明,1 180℃挤压空冷后Φ89 mm×15 mm GH4700管材的抗拉、屈服强度和伸长率分别为1 150 MPa、780 MPa和36%;合金在1 000～1 060℃固溶处理,随着温度的提高,γ'相逐渐溶入基体,合金晶粒明显长大,强度显著降低,塑性显著升高;在1 090～1 150℃随着温度的提高,晶粒长大趋势不明显,合金强度和塑性的变化趋势放缓。1 150℃固溶处理后GH4700合金抗拉强度800 MPa,屈服强度330 MPa,伸长率65%。

The effect of solid solution treatment at 1 000 - 1 150 ℃ on structure and mechanical properties of alloy GH4700 （/% ： 0. 05C, 25Cr, 20Co, 1.65Nb, 1.47Al, 1.69Ti, bal Ni） has been studied. Results show that the tensile, yield strength and elongation of Ф89 mm × 15 mm GH4700 alloy tube extruded at 1 180 ℃ , air cooling are respectively 1 150 MPa, 780 MPa, and 36% ; as the alloy solid-solution-treaded at 1 000 - 1 060 ℃ with increasing temperature the γ′ phase gradually dissolves into the matrix, the grains of alloy grow obviously, the strength decreases markedly and the plasticity rapidly increases; at 1 090 - 1 150 ℃ the trend of grain growth is not appreciable, the change trend of strength and plasticity of alloy is very slow; with solid-solution-treated at 1 150 ℃, the tensile strength, yield strength and elongation of alloy GH4700 are respectively 800 MPa, 330 MPa and 65%.