摘要
In this study,ceramics was prepared by slip casting(no pressure was used during shaping step)and atmospheric pressure sintering with low-melting point glass(LPG)powder as the binding material to facilitate the transformation of spodumene flotation tailings(SFTs)into ceramics at lower temperatures.The influence of sintering temperature and mass ratio of LPG on the mechanical properties(flexural strength and compressive strength)of ceramic materials was studied by orthogonal test.The results showed that when the mass ratio of LPG powder was higher than or equal to 20 wt%and the sintering temperature was higher than or equal to 550℃,mutual adhesion between the sample particles was realised and consequently the ceramic materials could be prepared with good mechanical properties(the maximum flexural strength=19.55 MPa,the maximum compressive strength=42.25 MPa,average porosity=24.52%,average apparent density=1.66 g/cm^(3),and average water absorption=14.79%).The sintered ceramics were characterized by XRF,XRD,optical microscopy analysis,SEM,TGA-DSC and FT-IR.The formation of liquid phase at high temperature may lead to the mutual bonding between particles,which might be the main reason for the improvement of mechanical properties of ceramic materials.Overall,SFTs were successfully sintered at low temperature to prepare ceramic materials with good mechanical properties,which are crucial for energy conservation and environmental preservation.
本文以锂辉石浮选尾矿为主要原料,低熔点玻璃粉(LPG)为高温粘结材料,通过湿法注模成型,常压烧结制备陶瓷材料。通过正交试验研究了烧结温度和LPG质量分数对陶瓷材料抗折强度和抗压强度的影响。结果表明,当LPG质量比不低于20 wt%,烧结温度不低于550℃时,尾矿颗粒间相互粘结紧密,制备出了力学性能优异的陶瓷材料(最大抗折强度=19.55 MPa,最大抗压强度=42.25 MPa,平均显气孔率24.52%,体积密度1.66 g/cm^(3),吸水率14.79%)。采用XRF、XRD、光学显微镜、SEM、TGA-DSC和FT-IR等对陶瓷材料低温烧结机理进行了测试分析。结果表明,高温下液相的生成使得颗粒间相互粘结可能为陶瓷材料力学性能提高的主要原因。
基金
Projects(51674207,51922091)supported by the National Natural Science Foundation of China
Project(2018QNRC001)supported by the Young Elite Scientists Sponsorship Program by CAST,China
Projects(2019YFS0453,2018JY0148)supported by the Sichuan Science and Technology Program,China。
