Effects of crack depth and shape on fracture toughness in a spring steel

✍ Scribed by Li Qingfen; Hu Shenghai; Pan Xinji

• Publisher: Elsevier Science
• Year: 1990
• Tongue: English
• Weight: 797 KB
• Volume: 36
• Category: Article
• ISSN: 0013-7944
• DOI: 10.1016/0013-7944(90)90090-4

✦ Synopsis

An experimental study described in this paper attempts to compare the behaviour of both through-cracked specimens with different a/w ratios and surface-cracked test pieces. Results show that the material is more resistant to crack growth when the a/Wratios are less than 0.1, both shallow throughand surface-cracked specimens, give a toughness value which is about 25% higher than the deep-cracked ones. But effect of crack shape on fracture toughness is negligible. For a/W larger than 0.1, the toughness K,, remains constant. Results also show that the LEFM approach to fracture is not tenable for design stresses where a, is often very small.