2026 알루미늄 합금에서 사전 변형이 시효 및 기계적 특성에 미치는 영향

초록

This study explores a method to enhance the precipitation hardening of AA 2026, an aluminumalloy superior to AA 2024, which is utilized in aerospace structural applications due to its high specificstrength and favorable precipitation hardening characteristics. The objective was to improve the alloy'smechanical properties by applying cold deformation prior to aging treatment, aiming to achieve weightreduction while meeting required strength specifications. The experimental procedure involved a solution heattreatment at 500oC for 4 hours, followed by cold tensile deformation ranging from 0% to 10%. Agingtreatments included both natural aging, conducted at room temperature for over 168 hours, and artificialaging at 190oC for durations of 4 and 8 hours. Results indicated that during natural aging, the yield strengthof AA 2026 increased in proportion to the extent of prior deformation, with minimal variation in thestrengthening effect across different deformation levels. In contrast, artificial aging led to a pronouncedincrease in yield strength that correlated with the amount of prior deformation, highlighting significantdifferences in both the aging strengthening effect and the aging kinetics. The findings suggest that the optimalaging condition for achieving a balance between elongation and strength is a pre-deformation of 3-5% followedby artificial aging at 190oC for 4 hours. Under these conditions, the alloy attained a yield strength exceeding500 MPa while maintaining an elongation of approximately 10%, demonstrating the potential for enhancedperformance in aerospace structural applications.

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