Mechanical Properties of Nano Particle Dispersed Aluminum Alloys and Elucidation of Their Strengthening Mechanism

本课题的目的是研究通过单辊淬火法制备的Al-Fe-Cr-Ti-M （M: Co和Ni）合金，再通过粉末冶金法制备少量Co或Ni以细化准晶颗粒分散的Al-Fe-Cr-Ti合金的力学性能，并阐明其强化机理。目前取得的部分结果如下：1)在铜辊（Vc）圆周速度为40 M /s的条件下，单辊法快速凝固（Al_<0.93>Fe_<0.03>Cr_<0.02>Ti_<0.02>）_<100-x>M_x （M:Co或Ni，x=0 ~ 3）合金的组织为非晶单相。2)在Vc=10 M /s下制备的快速凝固（Al_<0.93>Fe_<0.03>Cr_<0.02>Ti_<0.02>）_<100-x>M_x （M:Co或Ni，x=0 ~ 3）合金具有约50 nm的准晶颗粒均匀分散在fcc-Al相中的结构。3)在准晶颗粒分散的Al-Fe-Cr-Ti合金中，通过添加Co稳定过冷液相，通过控制Fe金属和Cr金属的最佳组成来细化准晶颗粒，具有准晶颗粒的形成能力。4)粉末冶金准晶颗粒分散Al_<91>Fe_5Cr_2Ti_1Co_1合金在573 K和673 K时的高温强度分别为365 MPa和208 MPa。5)准晶颗粒分散Al_<91>Fe_5Cr_2Ti_1Co_1合金表现出良好的热稳定性，即在573 k下保温200 h后，其组织和力学性能仍保持不变。6)准晶颗粒分散Al- fe - cr - ti - co合金在573 k下仍能进行压缩塑性工作。7)基于Orowan-Martin的沉淀硬化机理可以理解纳米颗粒分散Al基合金的强度。

The purpose of this project are to study of mechanical properties of the rapidly solidified Al-Fe-Cr-Ti-M (M : Co and Ni) alloys prepared by a single roller quenching method and then by powder metallurgy method, which added a small amount of Co or Ni in order to fine particles in quasicrystalline particle dispersed Al-Fe-Cr-Ti alloys reported previously by us, and to elucidate their strengthening mechanism.Parts of the results obtained up to now are described below :1)Structure of rapidly solidified (Al_<0.93>Fe_<0.03>Cr_<0.02>Ti_<0.02>)_<100-x>M_x (M:Co or Ni,x=0 to 3) alloys prepared by a single roller method at a circumferential speed of copper roller (Vc) of 40 m/s show an amorphous single phase.2)Rapidly solidified (Al_<0.93>Fe_<0.03>Cr_<0.02>Ti_<0.02>)_<100-x>M_x (M:Co or Ni,x=0 to 3) alloys prepared at Vc=10 m/s have the structure in which quasicrystalline particles of about 50 nm dispersed homogeneously in fcc-Al phase.3)Quasicrystalline particles in quasicrystalline particles dispersed Al-Fe-Cr-Ti alloys can be fined down by an addition of Co metal stabilizing the supercooled liquid state and by controlling optimum composition of Fe metal and Cr metal with forming ability of quasicrystalline particles.4)Powder metallurgy quasicrystalline particle dispersed Al_<91>Fe_5Cr_2Ti_1Co_1 alloys show high elevated temperature strength of 365 MPa at 573 K and 208 MPa at 673 K, respectively.5)Quasicrystalline particle dispersed Al_<91>Fe_5Cr_2Ti_1Co_1 alloys shows good thermal stability, that is, its structure and mechanical properties do not change even after holding 200 hr at 573 K.6)Quasicrystalline particle dispersed Al-Fe-Cr-Ti-Co alloys are capable of compression plastic working at 573 K.7)Strength of nano particle dispersed Al based alloys can be understood based on precipitation hardening mechanism by Orowan-Martin.