The present paper is concerned with the oscillatory stability and selection condition of dendritic growth from a system of binary mixture with enforced flow. We consider the case of large Schmidt number (Sc⪢1) and obtain the uniformly valid asymptotic solution by following the approach of the interfacial wave (IFW) theory of dendritic growth developed by Xu in the 1990s [Phys. Rev. A 43, 930 (1991); Phys. Rev. E 53, 5051 (1996)]. The results obtained show that the oscillatory wave instability mechanism explored in the IFW theory remains in the case under study. The quantitative changes in the critical number of stability criterion and selected condition for the velocity of the dendrite tip affected by the strength of the enforced flow are given under various growth conditions and material properties.

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A new kind of bainite steel with ultra-low carbon content and Nb, Ti alloys has been developed. By applying thermomechanical control process, water quenching and tempering at different temperature, excellent properties have been obtained when tempered at 450°C, with the yield strength of 813MPa and elongation of 16.2%. The morphology observed by SEM shows that the microstructure consists of fine lath-shaped bainite, polygonal ferrite, quasi-polygonal ferrite and a small fraction of residual austenite or martensite-austenite constituents. In a TEM study plenty of precipitates with the size about 5-10nm were observed interacting with the dislocations, which is very significant for the optimization of strength and ductility.

Comprehensive study is performed for the one-dimensional phononic crystals with locally resonant structures mechanism and Bragg scattering mechanism. Found locally resonant mechanism is same as Bragg scattering mechanism on one-dimension phononic crystal. The reasons of producing lower frequency band gap are still stiffness decrease and quality increase. So the theory that locally resonant structure is better than Bragg scattering in low frequency vibration reduction is inexact.