Author: William Leon Server Publisher: ISBN: Category : Languages : en Pages : 106
Book Description
The use of an instrumented impact hammer on pre-cracked Charpy V-notch specimens led to a reliable and inexpensive method for determining dynamic fracture toughness. Measurements were made on A-533, Grade B, Class 1 steel from -125F to +75F. The data were found to be in excellent agreement with those obtained by other workers on much larger specimens. Similar tests were run with standard Charpy V-notch specimens to determine dynamic tensile yield strength values. A comparison of the dynamic yield and toughness values suggests a meaningful technique for estimating the NDT temperature, which should be of practical value in nuclear reactor surveillance programs. (Author).
Author: GB. Lenkey Publisher: ISBN: Category : Dynamic fracture toughness Languages : en Pages : 16
Book Description
In the engineering practice it is of importance to know the effect of loading rate on the material behaviour, e.g., on the fracture mechanics properties. One of the most widely used testing techniques for determining these properties is the instrumented impact test. Depending on the material behaviour under a given loading condition, different fracture mechanics parameters should be determined. Most of the evaluation procedures of these parameters are still not standardised for higher loading rates. So the aim of the present work was to investigate the applicability of different methods for determining dynamic fracture toughness properties. Instrumented impact experiments combining with magnetic emission measurement have been performed on pre-cracked Charpy-V specimens of E420 C and QStE 690 TM high strength steels. Critical values of stress intensity factor (KId, KJi) related to the initiation of the fracture at different temperatures have been determined Using different methods depending on the type of the fracture.
Author: W. L. Server Publisher: ISBN: Category : Languages : en Pages : 27
Book Description
The use of an instrumented impact hammer on pre-cracked Charpy V specimens has led to an inexpensive method for determining the dynamic fracture toughness, K sub Id. Measurements were made on A-533 steel over a range of temperature ( -125 to + 75F) at a loading rate K clot approximately equal to 1,000,000 ksi (in. to the 1/2 power)/sec. The data were found to be in excellent agreement with those obtained by other workers on much larger specimens. Analysis of the data leads to a new method for estimating the NDT temperature, which may be of practical value in nuclear reactor surveillance programs. (Author).
Author: TJ. Koppenaal Publisher: ISBN: Category : Composite materials Languages : en Pages : 26
Book Description
The dynamic fracture toughness, KId, was measured in a number of ferrous alloys using precracked Charpy specimens and an instrumented impact machine. The alloys investigated included quenched and tempered steels (H-11, D6AC, and 4340), 18Ni maraging steels (grades 200, 250, and 300) and a high-temperature, stainless maraging steel (Pyromet X-15). Standard Charpy specimens were precracked in fatigue and tested at either 72°F (22°C) or -65°F (-54°C). Values of KId, were determined as a function of yield strength and microstructure, and correlations were established between KId and both the energy to initiate fracture, Wm/A, and the total energy of fracture, W/A. The instrumented, precracked Charpy test is shown to be a convenient method of determining relative fracture toughness; under proper conditions this test procedure can be used to determine the dynamic planestrain fracture toughness.
Author: G. Carcagno Publisher: ISBN: Category : Dynamic fracture testing Languages : en Pages : 17
Book Description
This paper presents a simple technique to determine dynamic J-R curves from a single, precracked Charpy-type specimen by means of an instrumented Charpy testing machine. This technique is based on the normalization method proposed originally by Landes and Herrera. This method eliminates the need for crack length monitoring that makes it particularly suitable under dynamic loading conditions.
Author: K. Ravi-Chandar Publisher: Elsevier ISBN: 0080472559 Category : Science Languages : en Pages : 265
Book Description
Dynamic fracture in solids has attracted much attention for over a century from engineers as well as physicists due both to its technological interest and to inherent scientific curiosity. Rapidly applied loads are encountered in a number of technical applications. In some cases such loads might be applied deliberately, as for example in problems of blasting, mining, and comminution or fragmentation; in other cases, such dynamic loads might arise from accidental conditions. Regardless of the origin of the rapid loading, it is necessary to understand the mechanisms and mechanics of fracture under dynamic loading conditions in order to design suitable procedures for assessing the susceptibility to fracture. Quite apart from its repercussions in the area of structural integrity, fundamental scientific curiosity has continued to play a large role in engendering interest in dynamic fracture problems In-depth coverage of the mechanics, experimental methods, practical applications Summary of material response of different materials Discussion of unresolved issues in dynamic fracture
Author: William Leon Server
Author: GB. Lenkey
Author: Welding Institute
Author: W. L. Server
Author: TJ. Koppenaal
Author: California. Office of Transportation Laboratory
Author: G. Carcagno
Author: T. S. DeSisto
Author: K. Ravi-Chandar
Author: American Society for Testing and Materials