From Charpy to Present Impact TestingBy
- D. Francois, Ecole Centrale de Paris, MSSMAT, Grande Voie des Vignes, Chatenay-Malabry, Cedex, 92292, France
- A. Pineau, ENSMP - Centre des Materiaux, BP 87, Evry Cedex, 91003, France
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.
For engineers and researchers specialising in the areas of structural integrity, impact testing, micromechanisms, polymers and computer modelling.
European Structural Integrity Society
Hardbound, 494 Pages
- Keynote Lectures.Historical background and development of the Charpy test (L. Tóth et al.).Micromechanisms and the Charpy transition curve (D. François).Finding Gc for plastics using modified Charpy tests(J.G. Williams, A. Rager).Modelling of the Charpy test as a basis for toughness evaluation (W. Schmitt et al.).Evolution of the Charpy-V test from a quality control test to a materials evaluation tool for structural integrity assessment (K. Wallin et al.).
Selected Papers.Micromechanisms.Instrumented testing of simulated Charpy specimens made of microalloyed Mn-Ni-V steel (S. Cvetkovski et al.).On the utilization of the instrumented Charpy impact test for characterizing the flow and fracture behavior of reactor pressure vessel steels (R. Chaouadi, A. Fabry).Ductile-brittle transition evaluation of Japanese sword and weld metals using miniaturized impact specimens (T. Misawa, S.I. Komazaki).
Polymers. Determination of rate dependent fracture toughness of plastics using precracked Charpy specimens (Z. Major, R.W. Lang).Determination of geometry-independent fracture mechanics values of Polymers (W. Grellmann et al.).
Test Procedures.Development in the instrumented impact test - computer aided instrumented impact testing systems (T. Kobayashi).Analysined from Charpy V and impact Tensile test (T. Kobayashi et al.).Dynamic fracture toughness determination using precracked Charpy specimens (D.M. Shuter).Use of instrumented Charpy impact tests for the determination of fracture toughness values (H.-W. Viehrig et al.).Use of Charpy impact testing to evaluate crack arrest fracture toughness (K. Müller, G. Pusch).Predicting crack arrest behaviour of structural steels using small-scale material characterisation tests (C. Gallo et al.).
Applications. Fracture toughness determination in the ductile-to-brittle transition regime - precracked Charpy specimens compared with standard compact specimens (J. Heerens, D. Hellmann).Correlating Charpy and J-fracture toughness parameters in structural integrity assessments (J.R. Tarpani, D. Spinelli).Statistical treatment of fracture mechanics data and correlation with Charpy energy (A. Mannsfeld et al.).An application of Charpy V testing: the pressure vessel surveillance program of nuclear pressurised water reactor in operation (N. Rupa et al.).European pipeline research group studies on ductile crack propagation in gas transmission pipelines (R.M. Andrews, V. Pistone).
Modelling. Charpy impact test modelling and local approach to fracture (A. Rossoll et al.).Experimental analysis of Charpy V-notch specimens (B. Tanguy et al.).Numerical modeling of Charpy V-notch tests (B. Tanguy et al.).Finite element simulations of sub-size Charpy tests and associated transferability to toughness results (C. Poussard et al.).