Development of technology for the viscosity measurement of Fe-S alloy melt using the new material anvil under high-pressure

我们开发了SiC/金刚石复合顶锤的制造技术，该顶锤具有比常规WC顶锤更高的硬度和抗压强度。我们评估了高压和高温产生的SiC/金刚石复合砧使用多砧高压装置（SPEED-Mk.II）结合同步辐射在Spring-8。在此基础上，我们还尝试了用落球法对Fe-S合金熔体进行粘度实验. SiC/金刚石复合顶锤的评价通过改变金刚石粉末与熔融Si的热等静压（HIP）合成条件，包括晶粒尺寸、温度、压力、真空度等，优化了SiC/金刚石复合立方体的制备方法，并将制备的边长为14 mm的立方体作为SPEED-Mk.II的第二级顶锤，它们表现出更高的压力和更高的温度世代，在室温下为38 Gpa，在17 G ...更多信息 在1600℃时，比WC立方块的抗压强度高。此外，我们还成功地合成了边长为26 mm的大尺寸SiC/金刚石复合立方体，并在20 Gpa的压缩试验后恢复完好. Fe-S合金熔体粘度实验的发展SiC/金刚石复合顶锤具有良好的X射线透过率（>30%），可用于X射线衍射或X射线照相研究。在SPEED-Mk. Ⅱ型实验机上进行了Fe_（90）S_（10）熔体的粘度实验，其第二级顶锤由四个SiC/金刚石复合体和四个WC立方体组成。研制了用于落球法的高压池，能够产生15 GPa和1600℃的高压，通过SiC/金刚石复合顶砧的穿透X射线，从CCD摄像机上观察到Fe 90 S 10熔体的良好X射线图像。然而，由于熔体与下落的金属球（Re、Ta、Au）之间的化学反应，粘度实验在P-T条件下是不成功的。需要进一步的技术改进来克服这一实验困难。少

We have developed the techniques for manufacturing the SiC/diamond-composite anvils, which have higher hardness and compressive strength than those of the conventional WC anvils. We evaluated the high-pressure and high-temperature generation of the SiC/diamond-composite anvils using a multi-anvil high pressure apparatus(SPEED-Mk.II) combined with the synchrotron radiation at the Spring-8. Based on the techniques, we also attempted the viscosity experiment of Fe-S alloy melt using the falling sphere method.1. Evaluation of the SiC/diamond-composite anvils We optimized the manufacture method of the SiC/diamond-composite cube by changing a hot isostatic pressing(HIP) synthesis conditions between diamond powders and molten Si, including the grain size, temperature, pressure, vacuum and so on. Fabricated cubes with 14 mm edge length were used as the second-stage anvils in the SPEED-Mk.II, and they showed higher-pressure and higher-temperature generations, 38 Gpa at room temperature and 17 G … More pa at 1600℃, than those by the WC cubes. Moreover, we successfully synthesized the large size SiC/diamond-composite cubes with 26 mm edge length, which were recovered without any damages after the compression test to 20 Gpa.2. Development of the viscosity experiment of Fe-S alloy melt The SiC/diamond-composite anvils show good X-ray transparency(>30%) enough for X-ray diffraction or radio-graphic studies. We attempted the viscosity experiments of Fe90S10 melt using the SPEED-Mk.II whose second stage anvils were composed of four SiC/diamond-composite and four WC cubes. Development of high-pressure cell for the falling sphere method enabled to generate 15 GPa and 1600℃, and we observed good radiographic image of Fe90S10 melt from CCD camera by penetrated X-ray through the SiC/diamond-composite anvils. However, because of the chemical reaction between the melt and the falling metal spheres(Re, Ta, Au), viscosity experiments were unsuccessful at the P-T conditions. Further technical improvements are needed to overcome this experimental difficulty. Less