A further study about the effect of crack depth and shape on fracture toughness

✍ Scribed by Li Qingfen; Hu Shenghai; Zhong Boming; Wei Jiaquan

• Publisher: Elsevier Science
• Year: 1991
• Tongue: English
• Weight: 872 KB
• Volume: 39
• Category: Article
• ISSN: 0013-7944
• DOI: 10.1016/0013-7944(91)90037-2

✦ Synopsis

Fracture toughness tests have been carried out on two different heat-treated steels 60Si2MnA using both through-cracked specimens with different a/W ratios and semi-elliptical cracked ones with variable crack size and shape. Effects of crack depth and shape on fracture toughness have been studied. Results show that the material is more resistant to crack growth when the a/W ratios are less than 0.1, both shallow through and surface-cracked specimens, give a toughness value which is about 25-30% higher than the deep-cracked ones. But the effect of crack length c and the ratio a/c on fracture toughness is negligible. Results also show that the LEFM approach to fracture is not tenable for design stresses where a, is often very small, far less than 2.5(K,,/u,.)z.