CAJ | 학술논문

高性能镁稀土合金中常常含有较多的贵重金属Y和Zr,研究用便宜的元素代替贵重元素而不影响力学性能具有重要的意义.利用OM,SEM-EDS,TEM-EDX研究了质量分数为0～1%的Al对Mg-5Gd合金显微组织、相组成的影响.结果表明:少量的Al能显著细化α-Mg枝晶,Gd与Mg形成Mg5Gd化合物,在晶界和晶内均匀分布.Al与合金中的Gd形成高熔点、硬质的、短棒状Al3Gd分布于晶界,并随着Al含量的增加,Al3Gd的数量增加.当Al含量超过0.8%后,Al与合金中的Mg形成脆性的Al12Mg17相,严重降低材料的塑性.
고성능미희토합금중상상함유교다적귀중금속Y화Zr,연구용편의적원소대체귀중원소이불영향역학성능구유중요적의의.이용OM,SEM-EDS,TEM-EDX연구료질량분수위0～1%적Al대Mg-5Gd합금현미조직、상조성적영향.결과표명:소량적Al능현저세화α-Mg지정,Gd여Mg형성Mg5Gd화합물,재정계화정내균균분포.Al여합금중적Gd형성고용점、경질적、단봉상Al3Gd분포우정계,병수착Al함량적증가,Al3Gd적수량증가.당Al함량초과0.8%후,Al여합금중적Mg형성취성적Al12Mg17상,엄중강저재료적소성.
High property magnesium alloys frequently contain expensive elments such as yttrium and zirconium.It is significant for this kind of alloys to develop inexpensive elment instead of expensive composition and do not decrease the property.The effect of 0~1% Al addition on microstructure characteristics and composition of second phases in Mg-5Gd alloys was discussed with OM,SEM-EDS and TEM-EDX. A remarkable grain refinement effect was found when a little of Al was added to the Mg-5Gd alloy. The second phase particles Mg5Gd, formed by Mg and Gd, distributed uniformly in α-Mg matrix and some clusters existed at the grain boundaries of Mg-5Gd alloy. A high melting point, hard, block-shaped phase Al3Gd, formed by Al and Gd, distributed at the grain boundaries and the amount of Al3Gd increased with the enhancing of Al content. When the content of Al exceeded 0.8%, the brickle phase Al12Mg17 was found in the Mg-5Gd-Al alloys.