Effect of microstructure on dynamic shear localisation in Alloy 718
Artikel i vetenskaplig tidskrift, 2017

The effect of microstructure on the strain localisation behaviour during dynamic shear deformation of Ni-Fe-base superalloy Alloy 718 was investigated by a combination of experiments and numerical simulations of Split-Hopkinson tests of specimens with top-hat geometry. The results show that strain localisation is promoted by small grain size and precipitation hardening, whereas large grains and solution annealing largely supressed the formation of shear bands. In addition, a smaller fillet radius facilitated the initiation of shear bands. Finite element simulations were able to reproduce the most important features of both global load–displacement histories, and presence of shear localisation. In particular, detailed simulations of the local deformation during localisation showed that temperatures exceeding 750?°C (locally above 1000?°C) and strain rates in the order of 2?105 s?1 were reached in the band.

Split-Hopkinson

Dynamic deformation

Shear localisation

Alloy 718

Numerical simulation

Författare

Joakim Johansson

Chalmers, Material- och tillverkningsteknik, Materialteknologi

Christer Persson

Chalmers, Material- och tillverkningsteknik, Materialteknologi

Gabriel Testa

Universita di Cassino e del Lazio Meridionale

Andrew Ruggiero

Universita di Cassino e del Lazio Meridionale

Nicola Bonora

Universita di Cassino e del Lazio Meridionale

Magnus Hörnqvist Colliander

Chalmers, Fysik, Biologisk fysik

Mechanics of Materials

0167-6636 (ISSN)

Vol. 109 88-100

Drivkrafter

Hållbar utveckling

Styrkeområden

Building Futures

Fundament

Grundläggande vetenskaper

Ämneskategorier

Metallurgi och metalliska material

DOI

10.1016/j.mechmat.2017.03.020