CAJ | 학술논문

使用半连续铸造法制备Mg-xGd-0.6Zr(x=2,4,6,质量分数)镁合金,研究不同Gd含量对Mg-xGd-0.6Zr合金组织与力学性能的影响,优化Mg-6Gd-0.6Zr合金的固溶处理工艺.采用光学显微镜、X射线衍射仪、扫描电子显微镜、能谱仪和显微硬度仪对合金的组织和力学性能进行表征.结果表明,随着合金中Gd含量的增加,晶粒尺寸略减小:Mg-xGd-0.6Zr合金的显微硬度与Gd的摩尔浓度呈线性关系.在铸造过程中由非平衡凝固形成的Mg2Gd和Mg3Gd在固溶处理时将转变成Mg5-05Gd平衡相;当固溶温度超过460℃时,Mg<,5.05>Gd溶解到a-Mg中.Mg-6Gd-0.6Zr合金的优化固溶处理工艺为(300℃,6 h)+(460℃,10 h).
사용반련속주조법제비Mg-xGd-0.6Zr(x=2,4,6,질량분수)미합금,연구불동Gd함량대Mg-xGd-0.6Zr합금조직여역학성능적영향,우화Mg-6Gd-0.6Zr합금적고용처리공예.채용광학현미경、X사선연사의、소묘전자현미경、능보의화현미경도의대합금적조직화역학성능진행표정.결과표명,수착합금중Gd함량적증가,정립척촌략감소:Mg-xGd-0.6Zr합금적현미경도여Gd적마이농도정선성관계.재주조과정중유비평형응고형성적Mg2Gd화Mg3Gd재고용처리시장전변성Mg5-05Gd평형상;당고용온도초과460℃시,Mg<,5.05>Gd용해도a-Mg중.Mg-6Gd-0.6Zr합금적우화고용처리공예위(300℃,6 h)+(460℃,10 h).
Mg-xGd-0.6Zr (x=2, 4, 6, mass fraction) alloys were prepared by semi-continuous casting process. The effects of Gd content on the microstructures and mechanical properties of Mg-xGd-0.6Zr alloys were studied and the solid solution treatment process of Mg-6Gd-0.6Zr alloys was optimized. The microstructures and mechanical properties of all the studied alloys were analyzed by optical microscope, X-ray diffraction, scanning electron microscope equipped with energy dispersive spectroscope and micro-hardness tester. The results show that the grain size slightly decreases with increasing Gd content and there is a close linear relationship between Gd content and micro-hardness of Mg-xGd-0.6Zr alloys. The second phases Mg2Gd and Mg3Gd formed due to non-equilibrium solidification during the casting process can be transformed into equilibrium phase Mg5.05 Gd which can dissolve into a-Mg solid solution phase at solution temperature of 460 ℃. The optimized solid solution treatment of Mg-6Gd-0.6Zr alloy is (300 ℃, 6 h) + (460 ℃, 10 h).