Determination of dynamic fracture-initiation toughness using a novel impact bend test procedure

Journal Article · Mon Nov 01 00:00:00 EST 1993 · Journal of Pressure Vessel Technology; (United States)

DOI:https://doi.org/10.1115/1.2929546· OSTI ID:5716649

Yokoyama, T ^[1]

---

1. Osaka Univ. (Japan). Faculty of Engineering Okayama Univ. of Science (Japan). Dept. of Mechanical Engineering

A novel impact bend test procedure is described for determining the dynamic fracture-initiation toughness, K[sub Id], at a loading rate (stress intensity factor rate), K[sub I], of the order of 10[sup 6] MPa [radical]m/s. A special arrangement of the split Hopkinson pressure bar is adopted to measure accurately dynamic loads applied to a fatigue-precracked bend specimen. The dynamic stress intensity factor history for the bend specimen is evaluated by means of a dynamic finite element technique. The onset of crack initiation is detected using a string gage attached on the side of the specimen near a crack tip. The value of K[sub Id] is determined from the critical dynamic stress intensity factor at crack initiation. A series of dynamic fracture tests is carried out on a 7075-T6 aluminum alloy, a Ti-6246 alloy and an AISI 4340 steel. The K[sub Id] values obtained for the three structural materials are compared with the corresponding values obtained under quasi-static loading conditions.

• OSTI ID: 5716649
• Journal Information: Journal of Pressure Vessel Technology; (United States), Vol. 115:4; ISSN 0094-9930
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
IMPACT TESTS
ALUMINIUM ALLOYS
BENDING
FINITE ELEMENT METHOD
FRACTURES
STEELS
STRESS INTENSITY FACTORS
TITANIUM ALLOYS
ALLOYS
CALCULATION METHODS
DEFORMATION
FAILURES
IRON ALLOYS
IRON BASE ALLOYS
MATERIALS TESTING
MECHANICAL TESTS
NUMERICAL SOLUTION
TESTING
420500* - Engineering- Materials Testing