The second phase in multi-phase alloys has connection with many important phenomena such as aging strengthening, dispersion strengthening, secondary hardening, crystal refinement. In this paper, the interface conjunction factors of the interface between MC(M=V, Nb, Ti) and austenite and martensite are calculate out. The relationship between these factors and the characteristics are analyzed. The reason for the second phases being fine and dispersing and their strengthening and toughening effect on the alloy is explained using the relationship. Based on the relationship, the valence electron structure of the interface between the second phase particles and the matrix can be optimized by changing the alloying elements, which make it possible to design the composition of alloys from the valence electron structure of the second phase particles.

In thermal barrier coatings (TBC), ceramics is covered on the metal matrix as coatings in order to raise its temperature endurance. Today most of the TBCs are of the double-layer-structure of Ni base heat-resistant alloy matrix + the bonding layer of MCrAlY alloy (M = Ni, Co, Ni + Co) + ZrO2. In this paper, the concept of interface conjunction factor (ICF) in the biphase interface of alloys is expanded to coatings. The ICFs of the interface between the ceramics and the bonding layers with various compositions, such as the electron density ρ, the electron density difference△ρ, and the number of atom state group which keeps the electron density continuous s are calculated. From the calculation results, the following estimations can be deduced. When Al content is less than 6 wt% it improves the mechanical properties of the coatings; when the content is 6 wt%—12wt% it will not worsen the properties; when the content is greater than 12 wt% it will have disadvantageous effect. The estimations accord well with the experiment results of the properties and the service time of the coatings. Therefore the concept of ICF has the same important meaning in coatings, and the valence electron structure of the interface can be a possible theoretical guide for the content optimization of TBCs.

Tempering is an important phenomenon in ferrous alloys. Most steels, especially alloying steels, are used after quenching and tempering. To design the composition of quenching and tempering steels, control the tempering process more effectively, improve the properties after tempering and realize the potentials of steels, the essence of tempering process and the properties of tempering products have to be understood. In this paper, the phase structure factors and interface conjunction factors of common alloying elements in cementite and its interface are calculated out. The relationships between these valence electron structure parameters and (i) the phenomena of martensite decomposition, (ii) transformation, gathering and growth of the carbides and (iii) the mechanical properties of tempering products are buitt up. The nature of the effect of alloying elements on tempering process and properties of tempering products is uncovered on the level of valence electron structure. One new theoretical foundation for alloy design is provided.

以固体与分子经验电子理论（EET）和改进的Thomas-Fermi-Dirac(TFD)理论为基础，以合金奥氏体、合金马氏体及其界面为例，给出了相结构因子nA, FDC,S和界面结合因子ρ，△ρ，σ的计算方法。计算了常用合金元素在0.2%C和1.0%C钢中的相结构因子和界面结合因子，用相结构因子和界面结合因子阐述了强韧性良好的20CrNi3钢和20Cr2Ni4钢的强韧化机制和耐磨性极高的ZGMn13耐磨钢的耐磨机制，并用相结构因子和界面结合因子预言了一种强韧性更高的Cr-Ni-W-V-0.2%C钢。结果与实际符合良好。

氧化锆陶瓷由于性能优异, 已得到了广泛的应用. 氧化锆陶瓷的相变影响其性能, 为控制相变进而控制性能, 相变机理的研究至关重要. 用固体与分子经验电子理论计算了c-ZrO2、t-ZrO2 和m-ZrO2 的价电子结构, 得到形成它们强键骨架的共价键上的总共价电子对数分别为3.19184、3.45528 和3.79625. 按固相合金中的C-Me 偏聚理论的思想推测ZrO2 从高温到低温的相变顺序应为液相→c 相→t 相→m相. 从价电子结构进行的推断与实验结果完全一致,说明合金相变的电子理论可以扩展到陶瓷材料中.