Abstract
While force–displacement curves are often preferred in Small Punch (SP) tests due to the ease of the experimental set-up, they encompass significant uncertainties arising from frame compliance. In this work, a methodology is presented to predict yield stresses from the force vs. deflection curves. The present method relies on determining different force levels from the initial part of the force–deflection curve to reflect both the slope and the curvature instead of using a single force level only. The predicted yield stresses for different types of materials, that is, low- and high-strength alloys, are found to be in good agreement with the actual proof stresses with a maximum error of 16%.
Highlights
Structural integrity assessment is critical for ensuring the safe operation and determining the residual lifetime of, for instance, power plant components
Force-displacement curves are popular due to the easy experimental set-up. They are sensitively affected by frame compliance effects, the accurate correction of which is difficult in practice
A new methodology to predict yield stresses from the force–deflection curves obtained by Small Punch (SP) testing has been presented
Summary
Structural integrity assessment is critical for ensuring the safe operation and determining the residual lifetime of, for instance, power plant components. With the adoption of the draft European standard CEN—prEN 10371 on Metallic materials-Small punch test method, SP testing is expected to further gain importance for design purposes, provided that robust methods are available for the correlation of SP test results with conventional tensile test results In this sense, the present work is to contribute a robust method for the derivation of tensile yield stresses from SP tests. In the case of deflection, the translation of the bottom of the specimen can directly be recorded by an LVDT or an extensometer that is placed underneath the specimen As an advantage, this configuration does not require any parasitic compliance correction, and reflects the actual material response. Considering the small range of deformation in the SP test, in particular, at the initial stage of relevance to yielding, the accuracy of the displacement measurement in practice is strongly affected by the frame compliance, thereby limiting the precision to which the yield stress can be determined. Chica et al [13] stated that both displacement and deflection curves resulted in the same accuracy of yield stress estimation and favoured displacement measurement for its simplicity
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
