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In order to clarify the reaction behaviour systemically between CaO and dephosphorisation slag, the solid CaO piece was dipped into the liquid slag and reacted for 5–300 seconds at 1573 K, the reaction mechanism between homogeneous CaO–SiO2–FeO–P2O5 slag and CaO was investigated in the present study. The results shows that 2CaO·SiO2 and 3FeO·P2O5 are the main phases in dephosphorisation slag, the enrichment phase of phosphorus were formed very fast in

In the present work, a melt spinning technique was employed to produce Ti51·5Ni48·5 shape memory ribbons. Two types of Ti2Ni particles were observed using high resolution transmission electron microscopy, and a model is proposed based on the microstructural observations. For the large Ti2Ni particles (∼300–500 nm), it is suggested that they are the product of an L32(Ti)+TiNi→Ti2Ni peritectic reaction, where the subscript stands for the Ni content. However, in the case of small particles, novel structures composed of a Ti-rich core and an amorphous shell layer are observed, which are the result of the rapidly solidified L(Ti)→β(Ti)+L24(Ti) and L24(Ti)→β(Ti)+Ti2Ni divorced eutectic process.

Excimer laser surface treatment of Ti–6Al–4V alloy was conducted with the aim of improving the pitting corrosion resistance of the alloy. Laser surface treatment was performed under two different gas environments, argon and nitrogen. The microstructure, phase and composition of the modified surface structure were analysed using TEM, XRD and EDX; the electrochemical behaviours of the untreated and the laser-treated specimens were evaluated by electrochemical polarization tests. Excimer laser surface treatment significantly increased the pitting potential of the Ti alloy, especially when the material was treated in argon gas, while a seven-fold reduction in corrosion current was obtained when the material was treated in nitrogen gas. These improvements are considered to be primarily due to the reduction of solute partitioning effect of detrimental Al segregated to the α phase. The N 2 -treated specimen, although it had the lowest corrosion current, had a pitting potential some 100 mV lower than that of the Ar-treated specimen. This is considered to be due to TiN precipitates acting as galvanic cathodes at high corrosion potentials.

Excimer laser surface treatment of 316LS bio-grade stainless steel (ASTM-F138) was conducted with the aim of enhancing the pitting corrosion resistance of the material. The experiment was performed under two different gas environments: air and nitrogen. The microstructure, phase and compositional changes after laser treatment were characterized by means of XRD, XPS and EDX; the resulting pitting corrosion resistance was evaluated by electrochemical polarization tests. The results show that excimer laser surface melting can effectively eliminate carbides and second phases alike, and also serves the function of homogenizing the microstructure. Nitrogen induced into the laser-treated surface could promote new precipitates and as a result lowered the corrosion resistance. On the other hand, laser treatment in a low partial pressure of nitrogen could enhance the corrosion resistance of 316LS stainless steel in that the active corrosion current was reduced and the passive range was widened.