Wei Xialu, Back Christina, Izhvanov Oleg, Khasanov Oleg L, Haines Christopher D, Olevsky Eugene A
Department of Mechanical Engineering, College of Engineering, San Diego State University, 5500 Campanile Dr., San Diego, CA 92182, USA.
General Atomics, 3550 General Atomics Ct., San Diego, CA 92121, USA.
Materials (Basel). 2015 Sep 10;8(9):6043-6061. doi: 10.3390/ma8095289.
Commercial zirconium carbide (ZrC) powder is consolidated by Spark Plasma Sintering (SPS). Processing temperatures range from 1650 to 2100 °C. Specimens with various density levels are obtained when performing single-die SPS at different temperatures. Besides the single-die tooling setup, a double-die tooling setup is employed to largely increase the actual applied pressure to achieve higher densification in a shorter processing time. In order to describe the densification mechanism of ZrC powder under SPS conditions, a power-law creep constitutive equation is utilized, whose coefficients are determined by the inverse regression of the obtained experimental data. The densification of the selected ZrC powder is shown to be likely associated with grain boundary sliding and dislocation glide controlled creep. Transverse rupture strength and microhardness of sintered specimens are measured to be up to 380 MPa and 24 GPa, respectively. Mechanical properties are correlated with specimens' average grain size and relative density to elucidate the co-factor dependencies.
商用碳化锆(ZrC)粉末通过放电等离子烧结(SPS)进行固结。加工温度范围为1650至2100°C。在不同温度下进行单模SPS时可获得具有不同密度水平的试样。除了单模模具设置外,还采用了双模模具设置,以大幅提高实际施加压力,从而在更短的加工时间内实现更高的致密化。为了描述SPS条件下ZrC粉末的致密化机制,使用了幂律蠕变本构方程,其系数通过对所得实验数据的反向回归来确定。所选ZrC粉末的致密化似乎与晶界滑动和位错滑移控制的蠕变有关。烧结试样的横向断裂强度和显微硬度分别测量高达380MPa和24GPa。将力学性能与试样的平均晶粒尺寸和相对密度相关联,以阐明共同因素的依赖性。