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By summarizing the research and development status of electro-thermal materials, this thesis puts its focus on the types, preparation methods and applications of non-metallic high-temperature electrothermal materials, and the comparative analysis of the advantages and disadvantages of such electric heating elements as SiC, ZrO2, LaCrO3and MoSi2. At last, the gap and the main problems existing between researches made on high temperature electrothermic materials at home and abroad are pointed out, as well as their prospected development trend.

An Fe/FeAl2O4 composite was prepared with Fe-Fe2O3-Al2O3 powder by a hot press sintering method. The mass ratio was 6:1:2, sintering pressure was 30 MPa, and holding time was 120 min. The raw materials for the powder particles were respectively 1 µm (Fe), 0.5 µm (Fe2O3), and 1 µm (Al2O3) in diameter. The effect of sintering temperature on the microstructure and mechanical properties of Fe/FeAl2O4 composite was studied. The results showed that Fe/FeAl2O4 composite was formed by in situ reaction at 1300 °C–1500 °C. With the increased sintering temperature, the microstructure and mechanical properties of the Fe/FeAl2O4 composite showed a change law that initially became better and then became worse. The best microstructure and optimal mechanical properties were obtained at 1400 °C. At this temperature, the grain size of Fe and FeAl2O4 phases in Fe/FeAl2O4 composite was uniform, the relative density was 96.7%, and the Vickers hardness and bending strength were 1.88 GPa and 280.0 MPa, respectively. The wettability between Fe and FeAl2O4 was enhanced with increased sintering temperature. And then the densification process was accelerated. Finally, the microstructure and mechanical properties of the Fe/FeAl2O4 composite were improved.

2system at 700°C. The results showed that so long as Cu appears or the electrodeposit process carries on, Cu++ can be reduced into Cu+; that the electrochemical reaction process of copper is a quasi-reversible process mix-controlled by ion copper diffusion rate and electron transport rate; that the electrochemical reaction mechanism is Cu++e-→Cu; that the electrocrystallization process of copper is an instantaneous hemispheroid three-dimensional nucleation process; that the Cu ion diffusion coefficient is 2.5×10-4cm2∙s-1at experimental conditions.