Quantitative analysis of ω-β phase transformation at 131 K enhanced by electron irradiation using a recent electron microscopy

β-Ti合金在时效、应力和冷却过程中发生ω相变。由于ω-相晶体的出现影响合金的物理性能，因此从工业角度研究了β-ω相的相变行为，阐明了β-ω相的相变机理，并计划收集定量分析β-ω相相变行为的数据，因为相变已经被应用于制造智能材料，并且它们的精确控制对于应用是重要的。（1）研究了在131 K下冷却形成的非晶态ω相晶体在四种不同条件下的电子辐照下的湮灭行为。实验在131 K下进行，采用原位观测技术。用TV-VTR系统记录了这些过程，并确定了湮灭的开始和结束时间。两种不同的湮灭起源 ...更多信息 s由于电子辐照已被认为是温度上升和辐射增强扩散。理论上估计的温升小于1度，但该估计没有考虑文献中提到的影响温升的样品表面污染的影响。由于样品表面通常被污染，因此考虑污染的影响成为一个问题。(2)Inβ-Ti合金发生β-ω-α相变。计划使用EELS技术澄清每个相的电子状态，以定量地理解该过程。采用两步老化法进行各工序的老化。在第二个过程中，不是ω-α相变，而是发生ω到新相变;出现新相。用电子衍射花样分析和高分辨电子显微镜方法研究了新相的晶体结构，但尚未弄清其结构，结果表明，在定量分析β-ω-α相变之前，存在两个问题。少

ω-phase transformation in β-Ti alloys occurs due to aging, stressing and cooling. Since appearance of ω-phase crystals affects physical properties of the alloys, the phase transformation has been investigated on the industrial viewpoint and to clarify the phase transformation mechanism.In the present work, a collection of data for quantitative analysis of β-ω phase transformation behavior has been planned, because phase transformations have been applied for making intelligent materials and their precise controlling is important for the applications. The following two experiments have been carried out:(1)Annihilation behavior of ahtermal ω-phase crystals, formed by cooling at 131 K was investigated under electron irradiations with four different conditions. The experiments have been carried out at 131 K using in-situ observation technique. The processes were recorded in TV-VTR system and starting and finishing times of annihilations were determined. Two different origins of annihilation … More s due to electron irradiation have been considered; temperature-rise and radiation enhanced diffusion. Theoretically estimated temperature-rise was less than 1 degree, but the estimation did not considered effects of contamination of specimen surface, which affects the temperature-rise, as mentioned in literatures. Since specimen surfaces are generally contaminated, it becomes a problem to consider effects of contamination.(2)In β-Ti alloys, β-ω-α phase transformation sequence occurs. It was planned to clarify electron states of each phase using EELS technique for understanding the process quantitatively. A two-steps aging method was adopted to occur each process. In the second process, instead of ω-α phase transformation, ω to a new phase transformation occurs ; a new phase appears. The crystal structure of new phase has been investigated using electron diffraction pattern analysis and HREM method, but the structure has not been clarified.The results obtained in the present work indicate that two problems exist prior to the quantitative analysis of β-ω-α phase transformation. Less