Effect of Relatively Low Levels of Porosity on the Plasticity of Metals and Implications for Profilometry-Based Indentation Plastometry


Change log
Abstract

jats:sec<jats:label />jats:pHerein, the effect of dispersed (relatively low levels of) porosity within a metal on its plastic deformation is examined. Stainless steel samples, made via additive manufacturing, are used in the work. It's found that porosity reduces stress levels during yielding and work hardening, approximately in proportion to the pore content. There is no significant difference between the strength of the effect during tension and compression, although porosity does reduce the tensile ductility. Finally, the profilometry‐based indentation plastometry (PIP) methodology (for obtaining stress–strain curves from indentation testing) are used. Porosity tends to bring the inferred yield stress down more strongly than during tensile testing and give higher initial rates of work hardening. This is associated with high local strains near the indenter causing closure of pores, so that volume is not conserved during the test. The resultant reduction in the pile‐up around the indent creates errors in the inferred stress–strain curve.</jats:p></jats:sec>

Description
Keywords
Gurson model, indentation plastometry, inverse finite-element method, porosity
Journal Title
Advanced Engineering Materials
Conference Name
Journal ISSN
1438-1656
1527-2648
Volume Title
Publisher
Wiley
Sponsorship
Engineering and Physical Sciences Research Council (EP/I038691/1)