烧结助剂对硼酸镁晶须晶体结构与抗压强度的影响

Influence of Sintering Additives on the Crystal Structure and Compressive Strength of Mg_2B_2O_5 Whisker

本研究以硼酸和碱式碳酸镁为原料,采用原位合成法制备了硼酸镁晶须,通过热分析(TG)、X射线衍射(XRD)和扫描电子显微镜(SEM)对样品进行表征,考察不同烧结助剂对硼酸镁晶须晶体结构、表面形貌、孔隙率及抗压强度的影响。实验结果表明,当未添加烧结助剂时,孔隙率为62. 57%,抗压强度为10. 32 MPa,晶须直径为0. 2~0. 6μm,长度为3~5μm。添加烧结助剂会降低硼酸镁晶须的孔隙率并提高其抗压强度。当烧结助剂为Mg F2时,孔隙率为51. 77%,抗压强度为14. 51 MPa;当烧结助剂为Na4P2O7时,孔隙率为43. 79%,抗压强度为21. 09 MPa。

Mg2B2O5 whiskers were prepared by in-situ synthesis method using H 3BO 3 and CH 4MgO 6 as raw material.The obtained Mg 2B 2O 5 whiskers were characterized by TG,XRD and SEM.The influence of sintering additives on the crystal structure and compressive strength of Mg 2B 2O 5 whiskers were investigated.The experimental results show that the porosity of Mg 2B 2O 5 whiskers is 62.57%,the compressive strength of Mg2B2O5 whisker is 10.32 MPa,the whisker diameter is 0.2-0.6μm,and the length is 3-5μm when no sintering aid is added.Addition of sintering aids reduces the porosity of magnesium borate whiskers and increases their compressive strength.When the sintering aid is MgF 2,the porosity is 51.77%,and the compressive strength is 14.51 MPa.The porosity is 43.79%and the compressive strength is 21.09 MPa when the sintering aid is Na 4P 2O 7.