(中南大学 粉末冶金国家重点实验室，长沙 410083)
摘 要: 采用熔炼铸造与锻造变形方法制备含0.3%Sc的AA7150铝合金。通过拉伸测试、剥落腐蚀测试、金相及透射电镜等技术方法，研究不同淬火工艺对锻造态铝合金性能及显微组织的影响。结果表明：铝合金在空气中自然冷却时，T6时效态合金的抗拉强度与抗剥落腐蚀性能层严重降低；而室温水淬的T6时效态合金比室温油淬的T6时效态合金具有更好的塑性。当预先采用(80 ℃，30 s)水淬火或(80 ℃，30 s)油淬火再15 ℃水淬时，T6时效态合金的抗拉强度明显得到提高，且抗剥落腐蚀性能也得到了改善。预先80 ℃淬火能提高T6时效态合金性能的主要原因是时效态合金晶界析出相的尺寸与离散度明显增大。
关键字: AA7150铝合金；淬火；力学性能；剥落腐蚀；显微组织
aluminum alloy AA7150 with minor Sc
（State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China）
Abstract:The aluminum alloy AA7150 with 0.3%Sc was prepared by melting and casting technique and forging deformation method. The effects of different quenching techniques on the tensile strength, exfoliation corrosion properties and microstructure of the alloy were investigated by using tensile testing, exfoliation corrosion, optical microscope and transmission electron microscopy (TEM). The results show that the air quenching at room temperature decreases the tensile strength and exfoliation corrosion-resistance properties of the alloy after aging at T6 treatment. The elongation of the alloy with water quenching at room temperature is higher than that of the alloy with oil quenching at room temperature. The tensile strength and exfoliation corrosion properties can be improved after (80 ℃, 30 s) water quenching+15 ℃ water quenching or (80 ℃, 30 s) oil quenching+15 ℃ water quenching. Prequenching at 80 ℃ can improve the grain boundary precipitation of the alloys, which is the reason why the properties of the alloy after aging at T6 treatment are improved.
Key words: aluminum alloys AA7150; quenching; mechanical properties; exfoliation corrosion; microstructure
