Comparison of three fracture toughness testing techniques using a dental glass and a dental ceramic
Comparison of three fracture toughness testing techniques using a dental glass and a dental ceramic
复制标题
DOI：
10.1016/s0109-5641(98)00032-3
复制
发表时间：
1998-07-01
期刊：
影响因子：
5
通讯作者：
Wiskott, HWA
中科院分区：
文献类型：
--
作者：
Scherrer, SS;Denry, IL;Wiskott, HWA
目标。文献中描述了旨在确定模型 l (K-lc) 中陶瓷断裂韧性的各种方法。 K-lc 的准确性、分散性和检查者间的重现性在很大程度上取决于程序方法、所使用的测试参数和样本的条件。本研究的目的是比较使用两种压痕方法以及新建立的断裂力学测试获得的断裂韧性值。方法。应用以下方法测定 K-lc：(1) 压痕断裂 (IF)、(2) 压痕强度 (IS) 和 (3) 单边 V 型缺口梁试验 (SEVNB)。测试的材料是低熔点玻璃（Duceram LFC）和长石基陶瓷（IPS classic）。数据通过ANOVA和Tukey's多重比较检验进行比较（p小于或等于0.05）。结果。对于这两种材料，IF 的 K-lc 变异系数范围为 10% 至 14%，IS 的 K-lc 变异系数范围为 7% 至 10%。 IS 技术证明了 IFS 瓷器的负载依赖性，而使用 IF 方法时未观察到这一点。 SEVNB 测试提供了一致的结果，变异系数在 1% 到 3% 之间。 IFS 瓷器的 SEVNB 韧性值与 IS 技术一致。然而，在所有 LFC 样本的凹口尖端观察到半便士形状的裂纹，从而导致 K-lc 值被低估。显着性。此类研究的总体目标是选择尽可能方便且可靠的测试程序。这项研究表明，所有三种方法的一致性都在 10% 以内。然而，没有一个程序被证明是绝对简单的。决定使用哪种方法应基于对每种技术固有的概念限制和技术困难的充分理解。 (C) 1999 年否认材料学院。由爱思唯尔科学有限公司出版。保留所有权利。
Objectives. Various methods aimed at determining the fracture toughness of ceramics in mode l (K-lc) have been described in the literature. The accuracy, scatter and the interexaminer reproducibility of K-lc depend strongly on the procedural approach, the test parameters used and the conditioning of the specimens. The purpose of the present study was to compare fracture toughness values obtained using two indentation methods as well as a newly established fracture mechanics test.Methods. The following methods for K-lc determination were applied: (1) indentation fracture (IF), (2) indentation strength (IS) and (3) the single-edge-V-notched-beam test (SEVNB). The materials tested were a low-fusing denial glass (Duceram LFC) and a feldspar-based porcelain (IPS classic). Data were compared by ANOVA and Tukey's multiple comparison test (p less than or equal to 0.05).Results. For both materials, K-lc coefficients of variation ranged between 10 and 14% for IF and 7 and 10% for IS. The IS technique demonstrated a load dependency for the IFS porcelain which was not observed when using the IF method. The SEVNB test provided consistent results with coefficients of variation between 1 and 3%. SEVNB toughness values for the IFS porcelain were in agreement with the IS technique. However, half penny shaped cracks were observed at the tip of the notch of all LFC specimens thus leading to underestimated K-lc values.Significance. The overall aim of this type of study is to select testing procedures that are as expedient and reliable as possible. This study has shown that all three methods agreed within 10%. However none of the procedures proved absolutely straightforward. Decision on which method to use should be based on a sound understanding of the conceptual limitations and technical difficulties inherent to each technique. (C) 1999 Academy of Denial Materials. Published by Elsevier Science Ltd. All rights reserved.