挤压及热处理工艺对Mg-Zn-Y组织及力学性能的影响

通过金相显微分析、X射线衍射、扫描电镜及拉伸试验等研究Mg-Zn-Y合金铸态、挤压态及热处理后显微组织及其力学性能的变化.结果表明,挤压后直接时效处理可使沉淀相大量析出,强化效果明显,可提高材料的力学性能.     

Mg—Li合金轧制制度研究

本研究表明Ｍｇ－１０．２Ｌｉ和Ｍｇ－１１．５Ｌｉ二元合金可轧制性优良，Ｍｇ－６．２Ｌｉ二元合金及Ｍｇ－７Ｌｉ－１４Ｚｎ基合金冷轧困难，但在热辊上（８０￣９０℃）易轧。正交实验研究了Ａｇ、Ｌａ、Ｎｄ、Ｃｅ对Ｍｇ－７Ｌｉ－１４Ｚｎ基体力学性能取向性的影响规律。     

三元系彩色热镀锌镀液的热力学性质

利用三元热力学性质的积分模型及活度系数解析式对Zn-Mn-Me和Zn-Ti-Me两系列三元合金镀液的组元活度及活度相互作用系数进行了计算．结果表明，Me为Ni和Cu时，均使呈色元素Mn或Ti的活度提高，Ni的影响程度比Cu显著得多；而Me为Ti和Mn时，Ti降低了Mn的活度；而Mn则提高了Ti的活度．通过与实验结果比较表明，镀液中溶质组元的活度与呈色效果之间有着必然的联系，即，凡是可以提高呈色元素活度的添加元素均有利于镀液综合性能的提高，从而最终优化呈色效果．因此，Mn，Ni和Cu均为彩镀液的有利元素，Ti的利弊与添加的相对量有关．     

Imitation design of temperature field in coloring hot dip galvanization process

Colors were generated by preferential oxidation of the metals in coloring hot dip galvanization process,and the evolution of temperature field during colling after hot dip would be responsible for the coloration results directly.Tht influences of bath temperature and velocity of steel stripmoving on temperature field of the strip were calculated in continuous coloring hot dip galvanization process by means of the ANSYS/Thermal module.The factors were considered including convection heat transfer,latent heat during cooling,and heat radiation in calculation.The effects of temperature field on coloration of sheet steel samples were investigated.     

Effect of rolling process on microstructures and mechanical properties of AZ31B alloy sheets

AZ31B magnesium extruded slabs prepared from LFEC were rolled at fairly lower temperature at 3, 6 and 16 m/min rolling speeds into 1 mm thickness. The results indicate that the microstructures achieved by rolling at low temperature or at low rolling speed are composed of many prismatic regions divided by shear strips due to pile-up of twin crystals; the prismatic regions increase at elevated rolling temperature or at high rolling speed, and finally all are composed of equiaxed crystals without twin crystals due to dynamic recrystallization. After optimizing control of rolling process, excellent mechanical properties would be acquired. The mechanical properties ofAZ31B sheet are ab=350 MPa, cr0.2=300 MPa, and 3=12.0% when rolled at 6 m/min. At the same time, the difference of mechanical properties between transverse and longitudinal direction reduced markedly.     

AZ91D镁合金近液相线铸造半固态坯料的部分重熔

对近液相线铸造AZ91D镁合金半固态坯料进行部分重熔，通过改变部分重熔时的加热温度和保温时间来研究其微观组织的演化规律，结果表明，适当控制加热温度和时间，坯料部分重熔时可获良好的触变结构，且坯料铸造时的高冷却速率因促进了坯料组织细化和蔷薇化而在部分重熔时加快固相颗粒球化进程并使球化效果改善、坯料在近液相线温度静置30min用水冷铁模浇注时，在575－580℃，保温15－30min可获得较理想的重熔结构，而用石墨模浇注时，则为580℃保温15－30min，研究还表明，重熔组织演化过程分球化预备，固相颗粒细化和球化及固相颗粒大长3个阶段，该进程是溶质和空位扩散以及相界面张车共同作用的结果，其中，前者在初期，后者在中后期起支配作用。     

电磁铸造镁合金大规格板坯偏析与组织研究

研究了不同铸造速度条件下截面尺寸为300 mm?800 mm的大规格AZ31镁合金板坯的宏观偏析及组织。结果表明,偏析区域出现在距离锭坯表面20 mm ~ 30mm范围内,板坯心部偏析小。宏观组织可分为表面激冷区,粗大的柱状晶区和内部等轴晶区。低速铸造可减轻宏观偏析,随铸造速度增加,整体晶粒尺寸先增大后减小,表面粗晶区宽度减小。高速铸造时晶粒尺寸最小,但不均匀。合理的铸造速度为32 mm/min。     

镁合金及其成形工艺与应用状况

综述了镁合金的种类、特点及性能，全面介绍了包括塑性成形、半固态成形、RSP等在内的镁合金成形方法，并对镁合金在航空航天、汽车、3C等工业的应用历史及现状进行了概述，分析了镁合金目前存在的问题，指出了下一步研究的重点，并展望了镁合金的发展前景。     

近液相线半连续铸造AZ91D镁合金微观组织研究

用近液相线半连续铸造法制备出具有球状和蔷薇状晶粒的AZ91D合金坯料。考察了铸造速度对合金微观组织的影响，以及对铸锭边部和中心组织差异的影响。实验结果表明，随铸造速度的增加，铸锭逐渐趋向枝晶化，边部和中心组织差异经历了由小到大，再由大到小的变化。并对铸造速度的影响机理进行了分析。