Abstract The zeta (ζ) potential of moderately concentrated (at 15 vol%) boron carbide (B4C) suspensions were characterised using electroacoustic spectroscopy. This technique has been validated for use in this application by correlating the ζ-potential to the suspension viscosity (at 30 vol%) across a range of pH values. Zeta potential has been shown to be effective in determining differences in B4C powders, reported to be nominally of the same specification in terms of particle size distribution and X-ray diffraction data. The isoelectric (IEP) points for three different as-received B4C powders were found to be 4, 7 and less than 2.5. The study showed that differences in ζ-potential across the powders can be minimised via heat treatment, which produced suspensions all with an IEP below 2.5. The study also established the effect of an anionic and a cationic dispersant on ζ-potential and rheology, demonstrating that excess dispersant from a ζ-potential perspective was required to obtain the lowest viscosity. The study concluded that as-received B4C powders most likely contain contaminants of a cationic nature and that electroacoustic spectroscopy is a useful tool in determining their behaviour in aqueous suspensions.

中文翻译：

---

使用电声光谱对碳化硼水悬浮液进行 zeta 电位和流变学研究

摘要 中等浓度（15 vol%）碳化硼 (B4C) 悬浮液的 zeta (ζ) 电位使用电声光谱进行表征。通过将 ζ 电位与一系列 pH 值范围内的悬浮液粘度（30 vol%）相关联，该技术已被验证可用于此应用。Zeta 电位已被证明可有效确定 B4C 粉末的差异，据报道，在粒度分布和 X 射线衍射数据方面，它们名义上具有相同的规格。发现三种不同的原样 B4C 粉末的等电 (IEP) 点分别为 4、7 和小于 2.5。研究表明，通过热处理可以最大限度地减少粉末之间 ζ 电位的差异，这会产生 IEP 均低于 2.5 的悬浮液。该研究还确定了阴离子和阳离子分散剂对 ζ 电位和流变学的影响，表明从 ζ 电位的角度来看，需要过量的分散剂才能获得最低的粘度。该研究得出的结论是，原样的 B4C 粉末很可能含有阳离子性质的污染物，并且电声光谱是确定它们在水性悬浮液中的行为的有用工具。