Influence of SiC/Silica and Carbon/Silica Interfaces on the High‐Temperature Creep of Silicon Oxycarbide‐Based Glass Ceramics: A Case Study
Influence of SiC/Silica and Carbon/Silica Interfaces on the High‐Temperature Creep of Silicon Oxycarbide‐Based Glass Ceramics: A Case Study
复制标题
DOI：
10.1002/adem.201800596
复制
发表时间：
2018-08
影响因子：
3.6
通讯作者：
C. Stabler;D. Schliephake;M. Heilmaier;T. Rouxel;H. Kleebe;M. Narisawa;R. Riedel;E. Ionescu
中科院分区：
文献类型：
--
作者：
C. Stabler;D. Schliephake;M. Heilmaier;T. Rouxel;H. Kleebe;M. Narisawa;R. Riedel;E. Ionescu
本文比较了三种不同相组成的SiOC微晶玻璃的高温蠕变行为。三种SiOC微晶玻璃都具有相同的玻璃状二氧化硅基质，但由不同的均匀分散相组成：1)只有球形的β-SiC纳米颗粒(以下简称为SiO_2/SiO_2)，2)只有高深宽比的杂化碳(即C/SiO_2)，以及3)两种相(碳化硅和分离碳，即C/SiO_2/SiO_2)。压缩蠕变实验的温度范围在1100到1300°C之间，真实应力在50到200兆帕之间。测得的SiOC微晶玻璃的蠕变激活能约为700kJ·−~(-1)，与相组成无关。应力指数约为2，表明变形机制为界面控制。所有SiOC微晶玻璃的蠕变粘度均显著高于玻璃二氧化硅微晶玻璃。令人惊讶的是，与高深宽比偏析碳相相比，球形β-SiC纳米颗粒对SiOC的有效蠕变粘度的影响更大。结果表明，β-SiC/SiO_2和C/SiO_2界面对硅氧碳化硅微晶玻璃的蠕变行为有不同的影响。
In the present study, the high‐temperature creep behavior of three SiOC glass ceramics with different phase compositions are compared by the authors. All three SiOC glass ceramics have a vitreous silica matrix in common, but comprise different homogeneously dispersed phases: 1) only spherical β‐SiC nanoparticles (sample denoted hereafter SiC/SiO2), 2) only high‐aspect ratio sp2‐hybridized carbon (i.e., C/SiO2), and 3) both phases (SiC and segregated carbon, i.e., C/SiC/SiO2). Compression creep experiments are performed at temperatures in the range between 1100 and 1300 °C and true stresses of 50 to 200 MPa. The determined activation energy for creep of the SiOC glass ceramics of around 700 kJ mol−1 is independent of the phase composition. A stress exponent value of approximately 2 indicates an interface‐controlled deformation mechanism. All SiOC glass ceramics exhibit significantly higher creep viscosities than that of vitreous silica. Surprisingly, the spherical β‐SiC nanoparticles have a higher impact on the effective creep viscosities of SiOC as compared to that of the high‐aspect ratio segregated carbon phase. It is concluded that this originates from the β‐SiC/silica and C/silica interfaces, which have different effects on the creep behavior of silicon oxycarbide‐based glass ceramics.