Microstructure of Al-4.99Zr-1.1B Master Alloy and Its Grain Refinement Effect on AZ31 Magnesium Alloy

作者：Wang Shuncheng^*; Gan Chunlei; Li Xiaohui; Zheng Kaihong; Qi Wenjun

来源：Rare Metal Materials and Engineering, 2014, 43(11): 2567-2571.

DOI：10.1016/s1875-5372(15)60002-9

• Al-Zr-B master alloy
• AZ31 magnesium alloy
• grain refinement
• heterogeneous nucleation

An Al-4.99Zr-1.1B master alloy was fabricated by in-situ synthesis from Al melt and K2ZrF4+KBF4 mixed powder. The microstructure of the Al-4.99Zr-1.1B master alloy and its grain refinement effect on AZ31 magnesium alloy were studied by XRD, OM, SEM and EDS. Results show that a large number of fine ZrB2 particles can be observed in the Al-4.99Zr-1.1B master alloy. With increasing the addition amount of Al-4.99Zr-1.1B master alloy, the primary alpha-Mg grains of AZ31 magnesium alloy are further refined and the network structure of the intermetallic beta-Mg17Al12 phase is changed into small blocky structure. Upon adding 0.6% Al-4.99Zr-1.1B master alloy, the average size of primary alpha-Mg grains is reduced from 170 mu m to 45 mu m. The present results indicate that the ZrB2 particles can act as the effective heterogeneous nuclei of alpha-Mg grains and is responsible for the grain refinement of AZ31 magnesium alloy.

• 出版日期2014-11
• 单位广州有色金属研究院