A parameter, notch insensitivity factor, has been derived in order to assess the stress concentration sensitivity of Al-Li based alloys. The effect of impurities and Ce element on the stress concentration sensitivity of Al-Li-Cu-Zr, Al-Li-Cu-Mg-Zr and Al-Li-Mg-Zr alloy sheets has been investigated and the dependence of the stress concentration sensitivity on the mechanical properties and microstructural parameters discussed. Deleterious impurities can enhance the stress concentration sensitivity especially for the conventional impurities in Al-Li-Cu-Mg-Zr alloy and for the alkali metal impurities in Al-Li-Cu-Zr alloy. Suitable Ce microalloying can reduce the stress concentration sensitivity to a certain degree and the benefit is more significant to the Al-Li-Cu-Zr alloy rich in the conventional impurities. When varying the composition systems, impurity kinds, impurity content, Ce element concentration and heat treating process makes the yield strength increase, fracture toughness decrease, partial recrystallised volume rise and grain size increase, the stress concentration sensitivity usually tends to increase. A special attention should be paid to the practical application of Al-Li alloys because there generally is high stress concentration sensitivity for the alloys as compared with conventional aluminum alloys.

The Ag/Cu bimetallic laminates were prepared by rolling bond at different temperature and annealing for different time at 673K and 1023K. Their microstructure, composition and hardness were investigated in the matrix or diffusion zone of the laminates. Dynamic recrystallization induced in rolling process produces the mixture microstructure containing deformed and equiaxial grains. There exists an incomplete recrystallized structure for the laminates annealed at 673K and a polygonal-grain structure for the laminates annealed at 1023K. The grain size in the strip matrixes increases with increasing rolling or annealing temperature. Recrystallization process during rolling or annealing causes the hardness reduction. The reduction is more significant in the Cu side of the laminates rolled at 873K and in the strip matrixes annealed for 0.5h. Faster velocity of Cu atom moving into the Ag side than Ag atom into the Cu side results in a position shifting of Cu concentration curve in the Ag side. The shifting becomes more significant with prolonging annealing time. In the Ag side of the laminates annealed at 1023K, there is a region of fine equiaxial grains along original interface and its width increases with prolonging annealing time. Some Cu-rich particles precipitate along grain boundaries in the fine grain region and can slightly harden the Ag strip component.

Cu-6wt%Ag and Cu-6wt%Ag-1wt%Cr microcomposites were prepared by heavy drawing. The morphology of filamentary bundles was observed and the tensile strength and electrical conductivity determined. The effect of Cr addition was discussed according to the changes in the microstructure, strength and conductivity with various draw ratios for both alloys.

制备了Cu-6%Ag及Cu-24%Ag合金铸锭并进行了均匀化处理。通过在合金中添加0.1%混合稀土的方法，研究了稀土元素对高Ag含量和低Ag含量两种合金原始组织的影响。稀土元素可在一定程度上使合金中的共晶体数量增加，细化低Ag含量合金的铸态α基体晶粒，降低高Ag含量合金中被连续网状共晶组织包围的枝晶轴间距。在均匀化退火过程中，稀土元素可明显细化在α基体中析出的次生相，并使共晶组织更趋于分散和向离异共晶形态发展。

The pyrite films with the thickness in 70-600nm were prepared by annealing the iron films with the thickness in 25-150nm at 673K. The structural, optical and electrical characteristics were investigated and the effect of film thickness on film properties was discussed. The pyrite films with different thickness have the optical absorption edges changed in the range 0.93-1.0eV. With increasing in film thickness, electrical resistivity tends to increase and carrier concentration tends to decrease. It is speculated that surface defects in thinner films could play a more important role in the effect on film properties whereas grain boundary defects in thicker films could play a more important role in the effect on film properties.