低温轧制超高强度Al-4Cu-3TiB2原位复合材料的强化机理

摘要

为了开发超高强度铝合金和评估各种强化机制对合金屈服强度的影响，将Al-4%Cu-3%TiB2进行低温轧制，然后再在175°C下快速退火、在125°C下时效。在总伸长率为9%的情况下，Al-4%Cu-3%TiB2原位复合材料得到800 MPa的高强度。使用标准方程来评估固溶强化、晶粒细化、位错强化、弥散强化和析出硬化等各种强化机制的贡献。其中贡献最大的是低温轧制引起的晶粒细化，其次是析出硬化、弥散强化。%Ultra-high strength Al alloy system was developed by cryorolling and the contribution of various strengthening mechanisms to the overall yield strength of the system was evaluated. Cryorolling of Al-4%Cu-3%TiB2 in situ composite followed by short annealing at 175 °C and ageing at 125 °C resulted in an ultra-high yield strength of about 800 MPa with 9%total elongation. The strengthening contributions form solid solution strengthening, grain refinement, dislocation strengthening, precipitation hardening and dispersion strengthening were evaluated using standard equations. It was estimated that the maximum contribution was from grain refinement due to cryorolling followed by precipitation and dispersion strengthening.