Measurement of fracture toughness K1c by single small-scale cylindrical specimen with ring-shaped crack

✍ Scribed by Chang Wang

• Publisher: Elsevier Science
• Year: 1987
• Tongue: English
• Weight: 522 KB
• Volume: 28
• Category: Article
• ISSN: 0013-7944
• DOI: 10.1016/0013-7944(87)90219-0

✦ Synopsis

In this paper the measurement of fracture toughness K1, by single cylindrical tensile specimen with ring-shaped crack is described. The specimen does not satisfy the size requirement for effective plane strain fracture toughness K,,. The principle assumed here is that the curve, normalizing the load versus load-displacement curve of small-scale speciment by a size parameter D (or other size in proportion to D), will contain all the normalized curves of the geometrically similar specimens with larger dimensions. The K,, value is obtained from the normalized P-A curve of the small-scale specimen and the equivalent energy concept. This value is lower than K1, obtained by standard methods, so it gives more safety in engineering calculations. In this paper, the experimentally obtained relation S/r s 1 and the linear relation between the size effects and the size parameter D have been proved. Also the equivalent energy method is extended from the compact tensile specimen to the cylindrical tensile specimen with ring-shaped crack.