The P92 steels were aged at 632°C for 500hrs and 1,000hrs, and creep ruptured at 650°C~625°C with stress of 120~110 MPa. The creep rupture life (CRL) of the aged samples was decreased with the aged time. The microstructure of the P92 steel was observed as fine tempered lath with dispersion of Cr-rich M23C6 along various grain boundaries. Upon aging and creep, recovery of lath and precipitation of coarse W-rich Laves phase were characterized as the main microstructural change. The M23C6 is relatively stable upon the short-term aging and creep. Decrease of the CRL of the aged specimens is considered as the degradations of microstructure such as the recovery of lath due to the dislocation annihilation and precipitation of coarse Laves phase.

By Monte Carlo method with EAM potentials, the specific heat of liquid Co50Fe50and Co48Fe48Th4alloys at different temperatures are obtained. The effect of Th on the thermophysical parameters is examined. Over the temperature range from 1400 to 2000 K, the specific heat decreases from to Jmol-1K-1after Th was added. It is the addition of Th element which has bigger atomic radius, larger atomic mass, and complex arrangement of extranuclear electron, leads to the reduced specific heat.

By establishing a diffusion model, the solute distribution is investigated during the growth of eutectic phase from the binary melt on the primary phase. Based on the eutectic reaction conditions, reasonable assumptions are carried out to build the partial differential equation. After the determination of the initial and boundary conditions, the analytical solutions have been derived from the method of variables separation. The solute distribution ahead of interface and the influence of this distribution on the growth rate of heteroepitaxial phase are discussed.

Solidification microstructure of Gd-16wt%Co master alloy is characterized by the primary (Gd), CoGd3, and Co7Gd12 dendrites plus (Co3Gd4+Co7Gd12) eutectic. In the laser melting conditions, the rapid solidification of melting pool shows three layers along the radial direction. The size of melting pool decreases with the increase of scanning speed. The dendrites are refined and the eutectic disappears in the pool. Near the top of the pool, the metastable phases and the peritectic reaction are restrained in the rapid solidification conditions.