CAJ | 학술논문

利用氮气雾化法制备了Al-Zn-Mg-Cu合金粉末,通过扫描电镜、光学显微镜和X射线衍射仪对粉末的形貌及组织特征进行了研究;检测了粉末热挤压法制备的合金棒材的力学性能,并对其断口进行了分析.结果表明:随着粉末颗粒尺寸减小,颗粒形状由以长条形为主转变为以近球形为主.同时,显微组织中的枝晶臂间距减小,晶粒细化效果明显;合金以α-Al相为主,还有少量η-MgZn_2平衡相存在.随粉末颗粒尺寸减小基体过饱和度增加,基体相和MgZn_2相衍射峰宽化;粉末粒度减小,挤压合金力学性能提高;挤压合金拉伸断口属于韧性断裂.
이용담기무화법제비료Al-Zn-Mg-Cu합금분말,통과소묘전경、광학현미경화X사선연사의대분말적형모급조직특정진행료연구;검측료분말열제압법제비적합금봉재적역학성능,병대기단구진행료분석.결과표명:수착분말과립척촌감소,과립형상유이장조형위주전변위이근구형위주.동시,현미조직중적지정비간거감소,정립세화효과명현;합금이α-Al상위주,환유소량η-MgZn_2평형상존재.수분말과립척촌감소기체과포화도증가,기체상화MgZn_2상연사봉관화;분말립도감소,제압합금역학성능제고;제압합금랍신단구속우인성단렬.
Al-Zn-Mg-Cu alloy powder was fabricated by nitrogen atomization process. The morphology and microstructure of powder, mechanical properties of extruded rods and fracture apperance were studied by scanning electronic microscope(SEM), optical microscope(OM) and X-ray diffraction (XRD). The result shows that morphology characteristics of powder changes from strip to near sphericity principally with decrease in size. At the same time, the dendritic arm spacing decrease, which is advantageous to grain refinement.The powder consist of α-Al and a spot of η-MgZn_2 equilibrium phase, whose diffraction peaks broaden with decrease of powder size and increase of degree of supersaturation. The mechanical properties of consolidated rods increase with decrease of initial powder size. Fracture morphology is ductile rupture.