Feldspar Ceramic Strength and The Reinforcing Effect by Adhesive Cementation Under Accelerated Aging

Abstract This study evaluated the effect of the accelerated artificial aging (AAA) on feldspar ceramic strength and the reinforcing effect promoted by adhesive cementation with resin luting agent. One hundred twenty feldspar ceramic disks were obtained. Sixty disks were acid-etched, silanized, and coated with an experimental resin luting agent simulating the adhesive luting procedures. Four groups were created (n=30): uncoated ceramic (control group), uncoated ceramic submitted to AAA, ceramic coated with resin luting agent, and coated ceramic submitted to AAA. Biaxial flexural testing with ball-on-ring setup was carried out. Biaxial flexural strength (s bf , MPa), characteristic strength (s 0 , MPa), and Weibull modulus (m) were calculated for axial positions z=0 (ceramic surface) and z=−t2 (luting agent surface). Data of s bf at positions z=0 and z=-t2 were separately submitted to statistical analyses (a=0.05). The uncoated ceramic submitted to AAA had no significant difference in s bf and s 0 compared with the control group. Resin coating of the ceramic increased s bf and s 0 at z=0. The AAA increased the s bf and s 0 for the resin-coated ceramic specimens at z=0 and also the s 0 at axial position z=-t2. The structural reliability at z=0 and z=-t2 was not influenced by the variables tested. In conclusion, resin coating improved the mechanical strength of the feldspar ceramic. The AAA procedure was not effective in aging the uncoated or resin-coated feldspar ceramic specimens.

摘要 本研究评估了加速人工老化（accelerated artificial aging, AAA）对长石陶瓷（feldspar ceramic）强度的影响，以及树脂粘接剂（resin luting agent）粘接所带来的增强效果。共制备120块长石陶瓷圆盘，其中60块经过酸蚀、硅烷化处理，并涂布实验用树脂粘接剂以模拟粘接操作流程。实验分为4组（每组n=30）：未涂布陶瓷组（对照组）、经AAA处理的未涂布陶瓷组、涂布树脂粘接剂的陶瓷组，以及经AAA处理的涂布树脂粘接剂的陶瓷组。采用球环法装置（ball-on-ring setup）开展双轴弯曲测试（biaxial flexural testing）。分别针对轴向位置z=0（陶瓷表面）与z=−t2（粘接剂表面），计算双轴弯曲强度（s_bf, MPa）、特征强度（s_0, MPa）与威布尔模量（Weibull modulus, m）。将轴向位置z=0与z=-t2处的双轴弯曲强度数据分别进行统计学分析（显著性水平α=0.05）。经AAA处理的未涂布陶瓷组，其双轴弯曲强度与特征强度与对照组无显著差异。在z=0位置，陶瓷表面涂布树脂粘接剂可提升双轴弯曲强度与特征强度。对于涂布树脂粘接剂的陶瓷试样，AAA处理可提升其z=0位置的双轴弯曲强度与特征强度，同时提升其在轴向位置z=-t2处的特征强度。轴向位置z=0与z=-t2处的结构可靠性不受所测试变量的影响。综上，树脂涂层可改善长石陶瓷的机械强度。加速人工老化流程对未涂布或涂布树脂涂层的长石陶瓷试样均未起到有效老化作用。