齿科二硅酸锂玻璃陶瓷的滑动磨损行为

在人工唾液润滑条件下,利用销—盘磨损试验机研究了齿科二硅酸锂玻璃陶瓷的滑动磨损行为.结果表明:二硅酸锂玻璃陶瓷的磨损过程呈现显著的跑合磨损期,且跑合期的磨损率远大于稳定磨损期的磨损率;减小原始表面粗糙度可缩短跑合期,降低跑合期的磨损率.在二硅酸锂玻璃陶瓷的显微组织中,虽然二硅酸锂晶体相比玻璃基体具有更高的硬度,但在跑合磨损期却更容易发生剥落磨损,造成跑合期磨损表面粗糙度的显著变化,这种现象可能与二硅酸锂晶体具有较低的弹性断裂应变能力(H/E比值)有关.

Sliding Wear Behavior of a Lithium Disilicate Glass-ceramic for Dentistry

Sliding wear behavior of a lithium disilicate glass-ceramic for dentistry was investigated using a pin-on-disk wear tester under the lubricating condition with artificial saliva. It is found that severe running-in wear exhibited because, the wear rate in the running-in region was much higher than that in the steady wear region. Decreasing the initial surface roughness of the wear surface shortened the running-in period and reduced the corresponding wear rate. Although the lithium disilicate crystalline phase in the microstructure of the glass-ceramic has higher hardness than the glass matrix, the crystalline phase was prone to spall predominantly in the running-in process, resulting in remarkable change of the worn surface roughness. The phenomenon was correlated with the lower elastic strain to failure (H/E ratio) of lithium disilicate crystalline phase.