[PDF] Standard Test Method For Impact Testing Of Miniaturized Charpy V Notch Specimens eBook

Author : Enrico Lucon
Publisher :
Page : 11 pages
File Size : 19,39 MB
Release : 2013
Category : Horticulture
ISBN :

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Small specimen test techniques are becoming ever more popular as the need increases to characterize mechanical properties by the use of the smallest possible amount of material, because of various restrictions on material availability, irradiation, testing space, and other factors. The National Institute of Standards and Technology (NIST) is currently developing certified miniaturized Charpy V-notch (MCVN) specimens for the indirect verification of small-scale impact testing machines. The same materials used for NIST standard verification specimens are being evaluated at three energy levels (low, high, and super-high). Two specimen types are being investigated, denominated KLST (from the German Kleinstprobe, or "small specimen") and RHS (reduced half-size). Several instrumented impact tests on miniaturized KLST and RHS specimens of low, high, and super-high energy have been performed and analyzed. The variability of MCVN data has been compared to that of full-size Charpy data from the same lots of test specimens. Although this can be considered as just the preliminary phase of this project, the results indicate that MCVN verification specimens can be used for the indirect verification of small-scale instrumented impact testers, both in terms of absorbed energy and maximum force.

Author : J. D. Splett
Publisher :
Page : 21 pages
File Size : 39,70 MB
Release : 2015
Category : Instrumented impact tests
ISBN :

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Small specimen test techniques are becoming ever more popular as the need increases to characterize mechanical properties by use of the smallest possible amount of material, because of various restrictions on material availability, irradiation, testing space, and other factors. The National Institute of Standards and Technology (NIST) recently qualified reference miniaturized Charpy V-notch (MCVN) specimens for the indirect verification of small-scale impact testing machines (with capacity in the range 15 J to 50 J and impact velocity around 3.8 m/s). The same materials used for NIST standard verification specimens were evaluated at three energy levels (low, high, and super-high). The miniaturized specimen type investigated is denominated KLST (from the German Kleinstprobe, or "small specimen"). In the first phase of the qualification activity, several instrumented impact tests on miniaturized KLST specimens of low, high, and super-high energy were performed and analyzed at NIST. In this part of the study, which was published elsewhere [Lucon, E., "Certified Miniaturized Charpy Specimens for the Indirect Verification of Small-Size Impact Machines," Mater. Perform. Character., Volume 2, No. 1, 2013], the variability of MCVN data was compared to that of full-size Charpy data from the same lot of specimens. Additional aspects were also investigated, such as the influence of shear lip symmetry and specimen full or partial fracture on absorbed energy, and the correlation between miniaturized and full-size Charpy data. In the second phase of the qualification activity, certified values of absorbed energy and maximum force were established for each energy level by means of an international round robin, which involved nine highly qualified laboratories. The results of this round robin, and the outcome of the statistical analyses performed in accordance with ASTM E691-13 (ASTM E691-13: Standard Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method, ASTM International, West Conshohocken, PA) and ISO 5725-2 [ISO 5725-2, 1994, "Accuracy (Trueness and Precision) of Measurement Methods and Results," International Organization for Standardization, Geneva, Switzerland], are presented in this paper. Complete details are provided by NIST [Lucon, E., McCowan, C., Santoyo, R., and Splett, J., "Standard Reference Materials--Certification Report for SRM 2216, 2218, 2219: KLST (Miniaturized) Charpy V-Notch Impact Specimens," NIST Special Publication 260-180, National Institute of Standards and Technology, Gaithersburg, MD, 2013], which accompanies the certified KLST.

Author : E. Lucon
Publisher :
Page : 17 pages
File Size : 38,48 MB
Release : 1998
Category : In situ temperature conditioning
ISBN :

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A suitable test technique and experimental procedure have been developed in CISE for instrumented impact testing of sub-sized Charpy specimens, both V-notched and fatigue precracked, on a 40 J small-scale drop-weight machine. The test technique will be described, including unusual test features, such as in situ temperature conditioning. The results of a series of tests performed on sub-size Charpy specimens will be presented, allowing the influence of various test parameters to be evaluated. Comparisons with standard, full-size specimen data will be presented and discussed as well. Finally, the activity of a Working Group on Instrumented Impact Testing of Miniaturized Charpy V-notch Specimens, active within ESIS Technical Committee 5 and chaired by the author, will be briefly described.

Author : Enrico Lucon
Publisher :
Page : 41 pages
File Size : 45,29 MB
Release : 2012
Category : Impact testing
ISBN :

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Small specimen test techniques become ever more popular as the need increases to characterize mechanical properties by use of the smallest possible amount of material, due to various restrictions on material availability, irradiation, testing space, and other factors. NIST is currently developing reference miniaturized Charpy V-notch (MCVN) specimens for the indirect verification of small-scale impact testing machines. The same materials used for NIST standard verification specimens are being evaluated at three energy levels (low, high and super-high). Two specimen types are being investigated, denominated KLST (from the German Kleinstprobe, or "small specimen") and RHS (reduced half-size). Several instrumented impact tests on miniaturized KLST and RHS specimens of low, high and super-high energy have been performed and analyzed. The variability of MCVN data has been compared to that of full-size Charpy data from the same lot of test specimens. Although this can be considered just the preliminary phase of this project, the results indicate that MCVN verification specimens can be used for the indirect verification of small-scale instrumented impact testers, both in terms of absorbed energy and maximum force. Additional aspects have also been investigated, such as the influence of shear lip symmetry and specimen fracture on absorbed energy and the correlation between miniaturized and full-size Charpy data.

Author : RB. Stonesifer
Publisher :
Page : 19 pages
File Size : 42,57 MB
Release : 2000
Category : Absorbed energy
ISBN :

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Two related standards are currently being developed by ASTM Subcommittee E 28.07.07. The first is focused on test procedures for instrumented impact testing. It is intended that ASTM Standard E 23 will eventually reference the instrumented test standard for tests conducted using conventional Charpy V-notch (CVN) specimens. The second new standard covers miniaturized Charpy V-notch (MCVN) testing. The Instrumented/Miniaturized Charpy Round Robin Test Program was established to support development of these standards. The goal of the program is to test CVN and MCVN specimens in the transition region and in the upper-shelf region using an instrumented striker system. The test procedure for the round robin is prescribed in the draft standards. A total of six specimens are being tested in the upper-shelf region and six in the transition region for two materials.

Author : D. Francois
Publisher : Elsevier
Page : 497 pages
File Size : 38,89 MB
Release : 2002-06-18
Category : Technology & Engineering
ISBN : 008052897X

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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.