Abstract
According to the problems of short life and low strength of TiB2 coating cathode for current technology in aluminium electrolysis industry, this work synthesized TiB2-TiB/Ti gradient composite with TiB2 coating and TiB whiskers in metallic Ti matrix by a electrolytic boronizing method based on similar density and thermal expansivity of the three materials. The phase composition and morphology of the cross-section were determined by X-ray diffraction (XRD), scanning electronic microscope (SEM) and X-ray energy dispersive spectrum (EDS). The results show that uniform TiB2 layer with a thickness of 8-10 μm is continuously coated on the surface while the TiB whisker connected with TiB2 layer was embedded dispersedly into the matrix. The TiB crystal whisker has a maximum length of about 220 μm. The growth rate of TiB2 and TiB is enhanced by the strong reduction of B4C. The novel gradient design of the composite helps to extend life and improve strength of the TiB2 cathode in aluminium electrolysis.
摘要
针对铝电解工业现有技术中TiB2 涂层阴极寿命短、强度低的问题,采用密度和热膨胀率相近的 三种材料的电解渗硼方法,合成了TiB2 涂层和TiB 晶须在金属Ti 基体中的TiB2-TiB/Ti 梯度复合材料。 采用X 射线衍射(XRD)、扫描电子显微镜(SEM)和X 射线能谱(EDS)等分析手段测定了材料的相组成 和截面形貌。结果表明,表面连续涂覆厚度为8–10 μm 的均匀TiB2 层,而与TiB2 层连接的TiB 晶须 分散嵌入基体中。TiB 晶须的最大长度约为220 μm,通过B4C 的强烈还原,TiB2 和TiB 的生长速率得 到提高,这种复合材料的新型梯度设计有助于延长TiB2 阴极在铝电解中的寿命和提高其强度。
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Huang, Yg., Wang, Y., Zhang, Xh. et al. Preparation of wettable TiB2-TiB/Ti cathode by electrolytic boronizing for aluminum electrolytic. J. Cent. South Univ. 26, 2681–2687 (2019). https://doi.org/10.1007/s11771-019-4205-5
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DOI: https://doi.org/10.1007/s11771-019-4205-5