A novel method for measuring plane stress dynamic fracture toughness

✍ Scribed by Yuanming Xia; Shiguo Rao; Baochang Yang

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 524 KB
• Volume: 48
• Category: Article
• ISSN: 0013-7944
• DOI: 10.1016/0013-7944(94)90139-2

✦ Synopsis

By using the self-designed Rotating Circular Disk direct tensile impact apparatus, a novel test method has been developed for studying the fracture properties of materials under impact loading. A double edge notch specimen under a plane stress state is used in fracture test conditions; the material exhibits elastic-plastic behavior at the crack tip. The SHPB technique is used to measure the dynamic loads and the displacements of the specimen; crack opening displacement is measured by applying the self-designed photoelectric transformation setup. For the evaluation of dynamic fracture toughness, the extended J-integral with the inertial effect is calculated by Rice's formula using the average load-displacement curve. The time to crack initiation is determined by the compliance changing rate method. The fracture toughness of LY12cz aluminum alloy at a loading rate km greater than lo6 MPa &sec is obtained.