A correlation between dynamic initiation toughness and crack arrest toughness

✍ Scribed by Jon Lereim

• Publisher: Elsevier Science
• Year: 1980
• Tongue: English
• Weight: 765 KB
• Volume: 13
• Category: Article
• ISSN: 0013-7944
• DOI: 10.1016/0013-7944(80)90087-9

✦ Synopsis

Dynamic initiation toughness values were obtained from testing small 3point bend specimens at -50, -2&O, + 23°C. Two specimen orientations were tested which showed no marked difference in critical dynamic initiation toughness. The obtained I& data were correlated with the crack arrest toughness Ku, and K,,. The value of K,, is in the range 0.93 to 1.29 times the corresponding fast fracture toughness, Kim, while the ratio KU/K, varies between 1.27 and 1.60.

NOTATION

The dynamic fracture resistance parameters which are used in this note are given below: crack tip opening displacement at initiation of dynamic crack propagation J-integral at initiation of dynamic crack propagation dynamic stress intensity factor at initiation of rapid crack extension derived from the obtained .f,.,

(& = [~I"')

min. value of the running stress intensity factor &, during fast fracture stress intensity factor at crack arrest of a fast fracture