We explore the distribution, morphology and structure of zirconium hydrides formed using different cooling rates through the solid state Zr+[H] → Zr + hydride transus, in fine and blocky alpha Zircaloy-4. We observe that cooling rate and grain size control the phase and distribution of hydrides formed. The blocky alpha (coarse grain, > 200 μm) Zircaloy-4, has a smaller grain boundary area to grain volume ratio and this significantly affects nucleation and growth of hydrides as compared to fine grain size (∼11 μm) material.

中文翻译：

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冷却速度和晶粒尺寸对Zircaloy-4中氢化物微观结构的影响

我们探索通过固态Zr + [H]→Zr +氢化物在不同的冷却速率下，在细小且块状的αZircaloy-4中形成的氢化锆的分布，形态和结构。我们观察到冷却速率和晶粒尺寸控制着形成的氢化物的相和分布。块状α（粗晶粒，> 200μm）Zircaloy-4，具有较小的晶界面积与晶粒体积比，与细晶粒（〜11μm）材料相比，这显着影响氢化物的形核和生长。