On the feasibility of the Chevron Notch Beam method to measure fracture toughness of fine-grained zirconia ceramics. Issue 10 (October 2016)

• Record Type: Journal Article
• Authors: Kailer, Andreas; Stephan, Marc
• Is Part Of: Dental materials. Volume 32:Issue 10(2016)
• Page Start: 1256
• Page End: 1262
• Publication Date: 2016-10
• Subjects: Zirconia -- Ceramics -- Chevron -- Fracture toughness testing -- Properties; Dentistry -- Periodicals; Dental materials -- Periodicals; 617.695
• DOI: 10.1016/j.dental.2016.07.011
• Languages: English
• ISSNs: 0109-5641

Abstract

Abstract: Objective: The fracture toughness determination of fine-grained zirconia ceramics using the chevron notched beam method (CNB) was investigated to assess the feasibility of this method for quality assurance and material characterization. Methods: CNB tests were performed using four different yttria-stabilized zirconia ceramics under various testing modes and conditions, including displacement-controlled and load-rate-controlled four point bending to assess the influence of slow crack growth and identify most suitable test parameters. For comparison, tests using single-edge V-notch beams (SEVNB) were conducted. Results: It was observed that the CNB method yields well-reproducible results. However, slow crack growth effects significantly affect the measured K IC values, especially when slow loading rates are used. To minimize the effect of slow crack growth, the application of high loading rates is recommended. Significance: Despite a certain effort needed for setting up a sample preparation routine, the CNB method is considered to be very useful for measuring and controlling the fracture toughness of zirconia ceramics.