Ti-B19钛合金的β→α＋β等温相变动力学

利用原位电阻法、同步X射线衍射等技术较为系统地研究了亚稳β钛合金Tj-B19的β→α＋β等温相变动力学。结果表明，在试验温度范围内，Ti-B19合金的等温相变为长程扩散控制的形核与长大过程，可以用JMA方程进行描述。在试验温度范围，500℃等温时效时相转变完成所需时间最短，相转变速度最快，当温度大于500℃时，随温度升高，相转变速度降低，这与相转变驱动力不足有关。当温度低于500℃时，由于受溶质扩散速度的影响，完成相转变所需时间更长。α相的数量是温度的函数，在500℃等温时，α相的数量最多，为57．7％，然后随温度的升高，α相的数量减少。根据试验结果，绘制了合金的时间-温度-转变量图（TTT图），其“鼻温”在500℃-550℃之间。     

Silfide: A System for Open Access and Distributed Delivery of TEI Encoded Documents

This paper presents some aspects of the Silfide server, a system dedicated to the delivery of linguistic resources on the web. After presenting the main issues behind the design of such a system, we focus on the editorial choices related to the use of the Text Encoding Initiative to represent our textual documents. In particular, we focus on the accommodations we have had to carry with regards to the TEI header and address the trade-off between extensive enrichment and genericity of the primary data when one wants to precisely mark-up a given document content. As a whole, we show how essential the TEI has proven to be for a project such as ours both from a practical and conceptual point of view.     

Microstructural formation in Ti alloys: In-situ characterization of phase transformation kinetics

The prediction of microstructure during processing needs to characterize the phase transformation occurring during the thermal treatments and their kinetics. In-situ high-energy synchrotron x-ray diffraction experiments performed during temperature variations allow the characterization of the phase evolution. For some transformation conditions, the continuous recording of diffraction diagrams evidences clearly intermediate phases. The quantitative analysis of the diffraction diagrams gives the transformation kinetics of each phase as well as their cell parameters. Transformation kinetics obtained by this method are compared to results obtained by electrical resistivity.