Download or read book Dynamic Fracture Toughness Determination by the Instrumented Charpy Impact Test written by California. Office of Transportation Laboratory and published by . This book was released on 1974 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book On the Determination of Dynamic Fracture Toughness Properties by Instrumented Impact Testing written by GB. Lenkey and published by . This book was released on 2000 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book Dynamic Fracture Toughness Papers written by Welding Institute and published by . This book was released on 1977 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dynamic Fracture Toughness Determined from Instrumented Pre Cracked Charpy Tests written by William Leon Server and published by . This book was released on 1972 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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).
Download or read book Single Specimen Fracture Toughness Determination Procedure Using Instrumented Impact Test written by Rauno Rintamaa and published by . This book was released on 1993 with total page 145 pages. Available in PDF, EPUB and Kindle. Book excerpt: A new single specimen test method and testing facility for evaluating dynamic fracture toughness has been develeoped. The method is based on the application of a new pendulum type instrumented impact tester equipped with an optical crack mouth opening displacement extensometer. The fracture toughness measurement technique uses the double displacement ratio method, which is based on the assumption that the specimen is deformed as two rigid arms that rotate around an apparent centre of rotation. This apparent centre moves as the crack grows, and the ratio of COD versus specimen displacement changes. As a consequence the onset of ductile crack initiation can be detected on the load-displacement curve. Thus an energy-based fracture toughness can be calculated.
Download or read book Introduction of a New Dynamic Fracture Toughness Evaluation System written by T. Kobayashi and published by . This book was released on 1993 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: Instrumented Charpy impact test has been widely used as a simple method for semi-empirically evaluating material impact toughness. The authors have developed a new instrumented Charpy impact testing system, which is called CAI (Computer Aided instrumented Charpy Impact testing) system. Using the CAI system, dynamic fracture toughness parameters such as Kd, Jd, Tmat, and various absorbed energies can be obtained from the load-deflection curve of a single precracked specimen for both ductile and brittle materials. It has been already put into practical use in Japan. This paper introduces the details of the toughness evaluation procedures in the CAI system.
Download or read book The Use of Pre Cracked Charpy Specimens to Determine Dynamic Fracture Toughness written by W. L. Server and published by . This book was released on 1971 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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).
Download or read book Dynamic Fracture written by K. Ravi-Chandar and published by Elsevier. This book was released on 2004-10-16 with total page 265 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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
Download or read book From Charpy to Present Impact Testing written by D. Francois and published by Elsevier. This book was released on 2002-06-18 with total page 497 pages. Available in PDF, EPUB and Kindle. Book excerpt: From Charpy to Present Impact Testing contains 52 peer-reviewed papers selected from those presented at the Charpy Centenary Conference held in Poitiers, France, 2-5 October 2001. The name of Charpy remains associated with impact testing on notched specimens. At a time when many steam engines exploded, engineers were preoccupied with studying the resistance of steels to impact loading. The Charpy test has provided invaluable indications on the impact properties of materials. It revealed the brittle ductile transition of ferritic steels. The Charpy test is able to provide more quantitative results by instrumenting the striker, which allows the evolution of the applied load during the impact to be determined. The Charpy test is of great importance to evaluate the embrittlement of steels by irradiation in nuclear reactors. Progress in computer programming has allowed for a computer model of the test to be developed; a difficult task in view of its dynamic, three dimensional, adiabatic nature. Together with precise observations of the processes of fracture, this opens the possibility of transferring quantitatively the results of Charpy tests to real components. This test has also been extended to materials other than steels, and is also frequently used to test polymeric materials. Thus the Charpy test is a tool of great importance and is still at the root of a number of investigations; this is the reason why it was felt that the centenary of the Charpy test had to be celebrated. The Société Française de Métallurgie et de Matériaux decided to organise an international conference which was put under the auspices of the European Society for the Integrity of Structures (ESIS). This Charpy Centenary Conference (CCC 2001) was held in Poitiers, at Futuroscope in October 2001. More than 150 participants from 17 countries took part in the discussions and about one hundred presentations were given. An exhibition of equipment showed, not only present day testing machines, but also one of the first Charpy pendulums, brought all the way from Imperial College in London. From Charpy to Present Impact Testing puts together a number of significant contributions. They are classified into 6 headings: •Keynote lectures, •Micromechanisms, •Polymers, •Testing procedures, •Applications, •Modelling.
Download or read book Measurement of Fracture Toughness by Instrumented Impact Test written by CE. Turner and published by . This book was released on 1970 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt: Previous studies of the Charpy impact test using instrumented pendulum or anvil with V-noteh steel specimens are reviewed. It is concluded that such results add little to the usefulness of the test since even cleavage fractures are normally well beyond yield. No fracture toughness index emerges other than the simple measure of energy from the pendulum. In a second generation of work, fatigue cracked and side grooved (fcsg) specimens promoted below yield fractures up to about the 50 percent fracture appearance transition temperature (fatt). These results have been analysed by linear fracture mechanics to give the dynamic fracture toughness KID. In this interpretation understanding of the oscillations in load records due to specimen vibration is important. Results are discussed in the light of recent studies including an analog model with which near quantitative agreement is found. An improved simple correction factor for inertia loading effects is presented. It is concluded from both this work and supporting measurements of KID by other techniques that dynamic fracture toughness KID can be measured for low-strength steels using the instrumented fcsg impact test subject to the precautions and corrections discussed. Typical values of KID for mild steel are 60 ksi ?in. at 0 C falling to 30 ksi ?in. at -60 C. The significance of these low values in relation to the much higher static toughness is discussed briefly.
Download or read book Dynamic Fracture Toughness Analysis of H 13 Hot Worked Die Steel by Instrumented Impact Testing written by D. Simon Shong and published by . This book was released on 1983 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dynamic Fracture Toughness Measurements of High Strength Steels Using Precracked Charpy Specimens written by TJ. Koppenaal and published by . This book was released on 1974 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book The Determination of Dynamic Initiation Fracture Toughness of Metals Using the Hopkinson Pressure Bar Loaded Instrumented Charpy Test written by Andrew Geoffrey Dutton and published by . This book was released on 1989 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Variables Affecting Reproducibility of the Instrumented Impact Test written by CH. Curll and published by . This book was released on 1977 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: Instrumented impact test systems have been designed for determination of dynamic fracture toughness properties and utilized for the study of impact properties of materials in many laboratories. Since equipment varies from laboratory to laboratory, variations due to the equipment or instrumentation or both should be examined. This investigation studies variations in dynamic fracture toughness due to the test machine or calibration methods or both. The parameters chosen for the study are the peak load and the fracture energy. Two materials, AISI-4340 steel alloy and 6061-T6 aluminum alloy, were selected to evaluate the variation of these parameters.
Download or read book Fast Fracture and Crack Arrest written by Gary T. Hahn and published by ASTM International. This book was released on 1977 with total page 438 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evaluation of Dynamic Fracture Toughness Using the Normalization Method written by G. Carcagno and published by . This book was released on 1993 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book The Development of Standard Methods for Determining the Dynamic Fracture Toughness of Metallic Materials written by DF. Cannon and published by . This book was released on 1992 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt: A simple, reliable, and repeatable method has been developed for determining dynamic plane-strain fracture toughness using an on-specimen strain gage. This extends the range of the British Standard Method for Determination of the Dynamic Fracture Toughness of Metallic Materials (BS 6729) to include measurement at impact testing rates. Dynamic finite element computing was used to optimize the position of the gage on the specimen. In tests at low loading rates on Charpy specimens, good agreement was found between toughness values calculated from the applied load and the calibrated gage, and with those measured by the shadow optic caustic technique. At higher rates, several gage types and two adhesives were compared. A satisfactory method was developed for performing tests at high and low temperatures. The technique was applied to larger bend specimens of two steels, and a test program was conducted at seven laboratories to assess the influence of testing machine and instrumentation variables. From the results, a standard calibration and test procedure has been developed.
