The effects of applied tensile stress on the microstructural stability of a third generation single crystal superalloy DD10 have been investigated under stressed and un-stressed thermal exposure at 980 °C. The results indicated that μ phase precipitated in the dendrite core after both stressed and un-stressed thermal exposure at 980 °C for 450 h. The μ phase formation, γ′ coarsening and rafting processes were promoted by the applied tensile stress. However, the precipitation of μ phase was not sensitive to the magnitude of applied tensile stress. Meanwhile, the applied tensile stress did not affect the type and morphology of the topologically close packed (TCP) phase. It is suggested that the interaction of the applied tensile stress and the misfit stress decreased the lattice misfit between μ phase and γ matrix and promoted the formation of μ phase.

The microstructure, tensile and stress rupture properties of K492Malloy have been investigated in the present study. The results revealed that γ matrix, γ′ phase, carbide and eutectic in the interdendritic region within grain interior and along grain boundary were observed after solidification. After heat treatment, γ' precipitates with two obviously distinct size existed in the dendrite core and interdendritic region, respectively. Meanwhile, the chain-like (W, Mo)6C and Cr23C6carbides precipitated along grain boundary. The investigation of mechanical properties suggested that the tensile strength was initially increased but then decreased with increasing the temperature from 25oC to 760oC. The stress rupture life was 68.2h and 35.8h at 760oC / 655MPa and 870oC / 365MP, respectively. The columnar grain and carbide along grain boundary resulted in intergranular brittle fracture in both test conditions. As a result, the elongation under the conditions of 760oC/655MPa and 870oC/365MP was 1.5% and 1.4%, respectively.

The strain caused by concrete shrinkage and creep is separated through the field measurement data in this paper. Then D62 model and ACI model of finite element model is established to predict shrinkage and creep. Compared with the measured data, the feasibility and practicability of these two models can be proved.

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This paper introduces the dynamic and space-time of architecture aesthetics, and gives the application of aesthetics in the modern architectural design, puts forward the design the building belongs to the times and nation, with the national culture and the whole human emotions. The concept of modern architectural design is to do the whole processing in the building color, proportion, texture. The building is through the transformation and the shape of the environment, the stunning beauty and education presented in front of us, embodies the unification of utility function and mental function of architectural beauty, this is also the significance of existence of architectural design.