连铸保护渣的好坏决定着铸坯表面质量以及连铸是否能够顺利进行.采用SHTT的方法研究了BaO和MgO质量分数对CaO-Al2O3系高铝钢保护渣熔化温度、结晶性能的影响.研究表明,MgO能够提高保护渣的熔化温度;保护渣的熔化温度随BaO质量分数的减少而升高.MgO可以抑制保护渣结晶;当BaO部分取代CaO时,随着BaO/CaO比例增大,保护渣结晶性能降低;同时BaO和MgO不影响连铸保护渣的晶体矿相和形态.

Hot compression tests of the homogenized Al-5.87Zn-2.07Mg-2.28Cu alloy were performed on the Gleeble-3180 thermal simulation machine at the temperature range of 350～450 ℃ and the strain rate range of 0.01～ 10 s-1.The results show that the power dissipation efficiency of the alloy is increased with increasing temperature and decreasing strain rate at each true strain.The flow instability region is enlarged and the optimum processing parameters of the alloy are changed with increasing strain.With increasing in deformation temperature and decreasing strain rate,the flow stress of the alloy is decreased,and the main softening mechanism is changed from dynamic recovery to dynamic recrystallization.When the temperature is 420 ℃,the dynamic recrystallization occurs at all strain rates.

中国文化与汉文化有着千丝万缕的联系，中文称汉语，人数最多民族的为汉族。因此笔者选取了与汉文化密切相关的“阿娇”典故作为研究对象。在日常生活中，我们经常使用“阿娇”、“金屋藏娇”等，但大多数人对“阿娇”典故的来源不是很清楚。为此笔者从典形、典义为脉络，对“阿娇”典故进行追根溯源。

利用Gleeble-1500热模拟试验机对均匀化7050铝合金在573～723℃和0.000 5～1 s-1变形条件下进行热压缩试验.通过线性回归分析计算出均匀化7050铝合金的应变硬化指数以及变形激活能,获得了均匀化7050铝合金热压缩变形条件下的流变应力本构方程.并借助扫描电镜(SEM)、电子背散射衍射(EBSD)和透射电镜(TEM)显微分析,对不同热变形条件下合金的微观组织演变进行研究.结果表明,均匀化7050铝合金在高温压缩变形过程中有动态回复和动态再结晶现象.髓着变形温度升高和应变速率下降,合金位错密度降低,流变应力减小.在热变形过程中,合金的主要软化机制由动态回复逐渐演变为动态再结晶,热变形组织由位错亚结构转变为再结晶组织.

The optical microscopy, orientation distribution function and scanning electron microscopy were used to investigate the fatigue properties and the rate of fatigue crack growth of 7475-T7351 alloy plate with thickness of 25 mm. The results show that the fatigue strength is anisotropic for the plate, it is 300 MPa along the transverse direction and 310 MPa along the longitudinal direction, respectively, and the fatigue life is longer than 1×107 cycle. Under the conditions of Kt=1, stress ratio R=0.1 and stress intensity factor amplitude ?K=30 MPa·m1/2, the fatigue crack growth rate da/dN along the longitudinal and transverse direction are 2.73×10?3?4.41×10?3 mm/cycle and 5.76×10?3?8.22×10?3 mm/cycle, respectively. The fatigue cracks mainly initiate on the non-metallic inclusions containing O, Na, Cl and coarse second phase on the sub-surface. A large number of striations are observed in the fatigue propagation zone, and a mixture of small dimples and cleavage is observed on the fracture surface in the fatigue fracture zone.

ITO nanopowder was preparated by liuquid chemical co-precipitation in the paper.The effects of pH of reaction end(7,8 and 9) and calcining temperature(350 ℃,650 ℃,750 ℃ and 850 ℃,respectively) on the propertie of ITO powder was investigated.It was characterized by TG-TDSC,XRD,SEM,HRTEM,FT-IR etc.The main results are as follows:Under the conditions of by adding sodium silicate in the liquid phase,reaction temperature of 60℃,the reaction end point at pH 8,the aging time for 60 min,calcined system for 2h and 750 ℃,the obtained ITO nano powder is In2O3 solid solution with a cubic structure,and is the single structure without SnO2 phase.ITO powder was prepared,which is nearly spherical,uniform particles and good dispersibility,particle size between 30~60 nm,specific surface area of 34.26 m2/g.And it has a high reflectivity as high as 66%~94% to infrared light in the range of the wave number of 840 to 3 164 cm- 1.

建立了地道桥与地基空洞的静力、动力模型,并进行非线性有限元计算.考察地基空洞对框架式地道桥受力状况的影响,分析了由地基空洞引起的框架式地道桥裂缝的发生机理,为框架式地道桥的设计、施工和裂缝防治提供了参考和依据.