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Hot stamping parts made of boron steel have been widely used in automotive industry. In forming process of a hot-stamped vehicle bumper, non-uniform contact and friction between the boron steel and tools caused the bumper groove sidewalls excessive thinning or crack. Increasing stamping speed could improve the non-uniformity of blank temperature field and reduce the temperature difference. Influence of the stamping speed and the friction on the forming quality were studied by numerical simulation. The results showed that increasing the stamping speed within a certain range or using reasonable lubrication could reduce the thickness reduction of the sidewall. A bumper without cracking was obtained with a high stamping speed of 300 mm/s and a certain lubrication method.

The two-mode phase field-crystal (PFC) method is used to simulate the nanograin growth, including the grain growth in different sets of crystal planes, the grain boundary structure with mismatch, the grain orientation and also the incoherent grain boundary in two dimensional plane. It is obviously observed that there are dislocation structures in nanograin boundary due to mismatch and misorientation of grains. These simulation results can not only be used in artificial controlling the grain boundary of nanograin, but also is of significant for designing new nanograin with a good grain boundary for structure materials.

The second phase nucleation and precipitation around an edge dislocation are studied using phase field method. A new free energy function including the elastic strain energy is established to describe the dislocation interaction with the solute. The results give the distribution of strain field of dislocation and show the precipitates grow up according to the power growth law with the index 2. The simulated results are in good agreement with that of theory of non-uniform nucleation.

The phase field method was applied to study the effect of second-phase particles (SPP) with different geometric orientations and shapes on grain growth. The results show that, in the grain growth process, most of the spherical second-phase particles located at triple junctions, while the stick SPPs located at the grain boundaries along the grain boundary. The second-phase particles are of the strong pinning effect on grain boundary and the limiting grain radius can be expressed by Zener relations. In the condition of the second-phase particles area fraction and size remaining the same, the stick SPPs are of more effective pinning on grain growth than that for spherical SPPs, and the orientation of disk second-phase particles is also an influence factor for pinning effect. Stick second-phase particles with multiple orientations can make a better pining effect than those with only one orientation.

Huashan granite-type uranium ore deposit is originated within the Huashan granite pluton in northeast of Guangxi, the mineral (mineralization) occurrences already found include Changchong, Baishijiao and Caomiping. Previous studies are relatively weak, especially in mineralogical characteristics, in this paper, a detailed study of minerals has been carried out through EPMA and EDS, the results show that the uranium mineral compositions of the three mineral (mineralization) occurrences are significantly different, but all of them are of secondary uranium minerals, among them, the main component of Changchong mineral (mineralization) occurrence is (meta-) autunite, of Baijiaoshi mineral (mineralization) occurrence is kasolite, and of Caomiping mineral (mineralization) occurrence is torbernite and zeunerite, which reflect the difference of their minerals sources.

The second phase nucleation and precipitation around the edge dislocation are studied using phase-field method. A new free energy function is established. The simulation results are in good agreement with that of theory of dislocation and theory of non-uniform nucleation.

In the plastic injection molding process, interaction between design and analysis is very intensive. However, current computer-aided systems (CAD and CAE) are realized as isolated modules. Thus, designers need to transform data models between CAD and CAE systems. Defects of many data errors and duplicated work are inevitable. This paper presents a CAD/CAE integrated system, building on top of existing CAD and CAE systems. The framework of the system is designed. A parametric integration model is established to achieve bidirectional association between the two systems. Details of key technologies in pre- and post- processing are discussed, such as mesh generation, feature recognition, and automatic evaluation of analysis results. A practical engineering case is studied to illustrate that the system can effectively avoid mesh repair and remodeling in pre-processing, reduce the dependency on experience in analysis result evaluation, and greatly improve the efficiency of iterative design-analysis-optimization process.