Be对AZ91镁合金组织、力学性能及耐腐蚀性能的影响

Effects of Be on Microstructure,Mechanical Properties and Corrosion Resistance of AZ91 Magnesium Alloy

研究了Be含量对AZ91镁合金的铸态组织、力学性能和耐腐蚀性能的影响。结果表明,AZ91镁合金中添加合金元素Be后,初生相α-Mg的大小以及γ-Mg17A112相的形态、大小与分布发生了明显的变化。Be对AZ91镁合金抗拉强度和伸长率的影响具有相似的趋势,即随着Be含量的增加,AZ91镁合金的抗拉强度和伸长率呈现先降后升、然后又降的趋势。当Be含量为0.15%时,抗拉强度和伸长率分别达到最大值167.74MPa和5.87%,分别比未添加Be时增加了11.4%和215.6%。AZ91镁合金中添加Be的腐蚀率均比未加Be时高,说明Be的加入可降低AZ91镁合金的耐腐蚀性能。

Effects of Be addition on the as-cast microstructure,mechanical properties and corrosion resistance of AZ91 magnesium alloy were described.It is indicated that size of primary α-Mg phase and morphology,size and distribution of γ-Mg17Al12 phase in microstructure can be greatly changed with the addition of Be into the AZ91 magnesium alloy.Meanwhile,with increasing in Be addition,tensile strength and elongation of the alloy are firstly decreased then increased and then decreased.Tensile strength and elongation of the alloy with 0.15% Be addition are 167.74 MPa and 5.87%,respectively,which are increased by 11.4% and by 215.6%,respectively,compared with those of the alloy without Be addition.The corrosion rate of the AZ91 magnesium alloy with Be addition is higher than that of one without Be,showing the deterioration of corrosion resistance of the alloy with Be.