摘要
为了研究微量Sc、Zr在Al-Mg-Mn合金中的作用,采用铸锭冶金方法制备了Al-6.0Mg-0.5Mn-(Sc、Zr)合金,通过光学显微镜、显微硬度、透射电镜组织观察和低频扭摆法测量内耗方法研究了微量Sc、Zr对Al-6.0Mg-0.5Mn的组织、再结晶行为及内耗性能的影响.研究表明:添加质量分数为0.21%Sc和0.15%Zr可显著细化Al-6.0Mg-0.5Mn合金铸态组织;粒状Al3Sc1-xZrx相对位错、晶界有强烈钉扎作用,抑制合金再结晶;冷变形后的Al-6.0Mg-0.5Mn-0.21Sc-0.15Zr合金的内耗表现出非线性特征,频率越低或温度越高,合金内耗Q-1越大.在频率为1Hz、应变振幅为4.6×10-5下,冷变形Al-6.0Mg-0.5Mn-0.21Sc-0.15Zr合金升温Q-1-T曲线上在326℃时产生内耗峰,该峰可由Al3Sc1-xZrx沉淀粒子与位错脱钉机制解释.微量Sc、Zr可以细化Al-Mg-Mn合金组织,抑制合金的再结晶,导致合金在升温Q-1-T曲线上产生内耗峰.
To study the effects of trace So, Zr on Al -Mg- Mn alloy, Al -6.0 Mg- 0. 5 Mn - （Sc,Zr） alloy were prepared by ingot metallurgy, and its microstructures, recrystallization processing and internal-friction properties were studied by means of optical microscope （OM） , micro-hardness testing, transmission electronic microscope （TEM） and low-frequency torsion method. Results show that, 0. 21wt. % Sc and 0. 15wt. % Zr can fine the casting mierostrueture of Al -6. 0Mg -0.5Mn alloy. The strong pin dislocation and grain boundary of AlSc1-xZrx particles prohibit.the alloy＇ s reerystallization. After 54% cold deformation, the Al- 6.0Mg- 0. 5Mn- 0. 21Se -0. 15Zr alloy shows non-linear internal friction character. The internal friction increases with the increased temperature and decreased tested frequency. An internal friction peak occurs at 326 ℃ in heating Q^-1- T curve tested at the frequency of 1 Hz and the strain amplitude of 4.6 × 10^-5, which is induced by dislocation interacting with fine precipitation particle Al3Sc1-xZrx, and can be explained by the mechanism of dislocation pull-ff from the pinned Al3Sc1-xZrx particles. It can be concluded that the trace So, Zr can fine the microstrneture and prohibit the reerystallization of Al- Mg - Mn alloy, and cause the appearance of internal friction in the alloy＇ s heating Q ^-1 - T curve.
出处
《材料科学与工艺》
EI
CAS
CSCD
北大核心
2009年第4期496-500,共5页
Materials Science and Technology
基金
国家十一五科研项目(YS-005-06)
