Use of Small Punch Notched Specimens in the Determination of Fracture Toughness

2008 ◽  
Author(s):  
Roberto Lacalle ◽  
Jose´ Alberto A´lvarez ◽  
Federico Gutie´rrez-Solana
Keyword(s):  
Fracture Toughness ◽  
Small Punch ◽  
Ship Building ◽  
Damage Models ◽  
Notched Specimens ◽  
Punch Test ◽  
Reduced Dimension ◽  
Fracture Tests ◽  
Lateral Notch

In recent years an increasing interest has been shown in materials characterisation techniques based on the use of reduced dimension samples. One of these techniques, first developed in the early 80’s, is Small Punch testing, in which a punch acts over a plane small specimen deforming it until fracture. So far, this test has been used as a tool for the estimation of mechanical properties, for characterising ductilebrittle transition or for knowing the evolution of these properties with ageing phenomena as neutron irradiation. The Small Punch Test has even been used in the determination of fracture toughness by means of indirect correlations or complex methodologies based on damage models and Finite Element simulations. In this paper, a direct methodology for the determination of fracture toughness from Small Punch tests is proposed. The approach is based on the use of simply modified Small Punch specimens in which a lateral notch was machined. Attending to energy considerations, the J-Δa curve for a ship-building Grade A steel, as well as for a structural steel, E690, has been obtained using this type of samples and the results have been compared with the calculated results from conventional fracture tests.

Determination of Material Fracture Toughness by Circular Pre-Cracked Small Punch Test Specimens

2019 ◽  
Vol 795 ◽  
pp. 165-171
Author(s):  
Wu Lin Wang ◽  
Du Wei Wang ◽  
Kai Shu Guan
Keyword(s):  
Fracture Toughness ◽  
Empirical Correlation ◽  
Fracture Toughness Test ◽  
J Integral ◽  
Small Punch Test ◽  
Small Punch ◽  
Punch Test ◽  
Determination Procedure ◽  
Material Fracture

Fracture toughness empirical correlation between SPT(Small Punch Test) with non-crack sample and standard fracture toughness test has been established in recent years. In order to compensate the imperfection of empirical correlation, such as absence theoretical basis, poor repeatability and universality, in this paper, an O-type pre-cracked sample was adopted to evaluate fracture toughness. The mechanical model of the sample is in compliance with plane strain condition in the direction of crack propagation. In this paper a determination procedure was studied and established, and the J-integral of steel Q345R was calculated using the procedure.

Rate effects on the estimation of fracture toughness by small punch tests in hydrogen embrittlement

2019 ◽  
Vol 54 (7-8) ◽  
pp. 390-400 ◽  
Author(s):  
Borja Arroyo ◽  
Jose Alberto Álvarez ◽  
Federico Gutiérrez-Solana ◽  
Roberto Lacalle ◽  
Pablo González
Keyword(s):  
Fracture Toughness ◽  
Hydrogen Embrittlement ◽  
Slow Rate ◽  
Environment Interaction ◽  
Small Punch Test ◽  
Small Punch ◽  
Notched Specimens ◽  
Punch Test ◽  
Material Environment ◽  
Rate Effects

In this article, different techniques to test notched small punch test samples in fracture conditions in aggressive environments are studied, based on the comparison of the micromechanisms at different rates. Pre-embrittled samples subsequently tested in air at rates conventionally employed (0.01 and 0.002 mm/s) are compared to embrittled ones tested in environment at the same rates (0.01 and 0.002 mm/s) and at a very slow rate (5E–5 mm/s). A set of samples tested in environment under a set of constant loads that produce very slow rates completes the experimental results. As a conclusion, it is recommended to test small punch test notched specimens in environment at very slow rates, of around E–6 mm/s, when characterizing in hydrogen embrittlement scenarios, in order to allow the material–environment interaction to govern the process.

scholarly journals Determination of Strength and Fracture Toughness of Small Ceramic Discs Using the Small Punch Test and the Ball-on-three-balls Test

2014 ◽  
Vol 3 ◽  
pp. 961-966 ◽  
Author(s):  
Stefan Rasche ◽  
Stefan Strobl ◽  
Meinhard Kuna ◽  
Raul Bermejo ◽  
Tanja Lube
Keyword(s):  
Fracture Toughness ◽  
Small Punch Test ◽  
Small Punch ◽  
Punch Test

scholarly journals Analysis of the Hydrogen Induced Cracking by Means of the Small Punch Test: Effect of the Specimen Geometry and the Hydrogen Pre-Charge Mode

Proceedings ◽  
2018 ◽  
Vol 2 (23) ◽  
pp. 1418
Author(s):  
Guillermo Álvarez Díaz ◽  
Pablo Vinjoy Rodríguez ◽  
Mario López Gallego ◽  
Cristina Rodríguez González
Keyword(s):  
Structural Steels ◽  
Gaseous Hydrogen ◽  
Small Punch Test ◽  
Small Punch ◽  
Notched Specimens ◽  
Punch Test ◽  
Hydrogen Induced Cracking ◽  
Simplified Procedure ◽  
Charge Mode ◽  
Lateral Notch

This paper presents a simplified procedure to analyse the Hydrogen Induced Cracking (HIC) of structural steels by means of the Small Punch Test (SPT). Two types of notched specimens were used: one with through-thickness lateral notch and another with surface longitudinal notch. The results for conventional specimens were compared with those for hydrogen pre-charged specimens. For this purpose, two different methods to introduce hydrogen in the specimens were used: cathodic/electrochemical pre-charging and pressurized gaseous hydrogen pre-charging. The results obtained with both methods are also discussed.

scholarly journals Possibility to Estimate Fracture Toughness of Ductile Steel Materials from Small Punch Test Data

2015 ◽  
Vol 130 ◽  
pp. 1029-1038
Author(s):  
J.-Y. Jeon ◽  
Y.-J. Kim ◽  
J.-W. Kim ◽  
S.-Y. Lee
Keyword(s):  
Fracture Toughness ◽  
Test Data ◽  
Small Punch Test ◽  
Small Punch ◽  
Punch Test ◽  
Ductile Steel

Application of Miniature Small Punch Test Specimen in Determination of Tensile Properties

2015 ◽  
pp. 1-8 ◽  
Author(s):  
R. Kopriva ◽  
M. Brumovsky ◽  
M. Kytka ◽  
M. Lasan ◽  
J. Siegl ◽  
...  
Keyword(s):  
Tensile Properties ◽  
Test Specimen ◽  
Small Punch Test ◽  
Small Punch ◽  
Punch Test

Determination of creep property of 1.25Cr0.5Mo pearlitic steels by small punch test

2013 ◽  
Vol 28 ◽  
pp. 215-221 ◽  
Author(s):  
Feng Hou ◽  
Hong Xu ◽  
Yucheng Wang ◽  
Li Zhang
Keyword(s):  
Creep Property ◽  
Small Punch Test ◽  
Small Punch ◽  
Punch Test

Fracture Toughness and Cracking Behaviour of SCC Compared to VC

2013 ◽  
Vol 577-578 ◽  
pp. 205-208
Author(s):  
Sara Korte ◽  
Veerle Boel ◽  
Wouter de Corte ◽  
Geert de Schutter
Keyword(s):  
Fracture Toughness ◽  
Fracture Process ◽  
Critical Value ◽  
Fracture Parameter ◽  
Self Compacting Concrete ◽  
Bending Tests ◽  
Three Point Bending ◽  
Notched Specimens ◽  
Subsequent Determination

Vibrated concrete (VC) and self-compacting concrete (SCC) have a substantially different composition, resulting in dissimilar mechanical properties regarding cracking behaviour. The critical value of the mode I stress-intensity factor KICis an appropriate fracture parameter for evaluating fracture toughness and can be obtained from three-point bending tests (3PBT) on small, notched specimens. Subsequent determination of the energy release rate thus allows to examine the crack propagation and fracture process of both concrete types. This paper describes the results of such 3PBTs on samples, made from VC and SCC. Evaluation of the cracking behaviour, derived from these results, reveals remarkable differences.

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