Preparation and properties of gradient structure concrete member
Based on the dense packing powder theory, the refining and self-healing principles, and hydrophobic treatment, the special surface-layer materials and design are proposed in gradient structure concrete (GSC) member. According to service behavior, the GSC member is divided into serial structure and parallel structure. And it is fabricated corresponding to structural parameters by stacked press process, or pulled clapboard method, or suspended nets method. Use of small and full scale specimens for testing, the results are shown that: 1) the surface-layer strength of the GSC component improved by 30%, compared to that of a conventional single-layer component; 2) the width of the crack ranges from 0 to 0.1mm in the GSC component, whereas a conventional single-layer component are distributed with visible cracks(0.2–0.5mm);3) The permeating depth and chloride diffusion coefficient of the GSC component is respectively 0mm and 6.3×10–13 m2/s, whereas a conventional single-layer component is 15mm and 12.8×10–13 m2/s.
STRUCTURE DESIGN AND PERFORMANCE ADJUSTMENT OF DECORATE CONCRETE
From the point of gradient material, the function-structure compound design was put forward. Double structure or multiple structure were selected according to different functional requirement. The decoration and property optimization of the whole structure could be realized by adding the design of functional structure on the common concrete. The coated surface layer, decorative function layer and basic structure layer were combined organically by using the special construction technique. The test results show that the three stage gradient changes of the decoration and the physical mechanical performance are realized through the scientific design of materials and structures, such as: gradient changes as strength of 90-70, 80-40, 50-30 MPa and ion diffusion of 667,780-(1 000), (1 310) C etc. The optimization of the material, structure and performance are obtained through it.
Synthesis of TiC, TiC-Cu Composites, and TiC-Cu Functionally Graded Materials by Electrothermal Combustion
Titanium carbide and composites and functionally graded materials (FGMs) of TiC-xCu were synthesized by an electrothermal combustion (ETC) method. TiC synthesized by ETC showed small amounts of porosity relative to those synthesized by ignition using radiative heating. Composites and FGMs with higher copper content can be synthesized by ETC. In the FGM products a nearly linear change in composition in the graded region was observed in samples with 0 ≤ x (wt%) ≤ 75.