Fracture mechanisms of spinodal alloys

ABSTRACT

Fracture surface retains an of the entire deformation history undergone in a material. Hence, it is possible to derive the approximate deformation and fracture properties of a material from a systematic quantitative fractographic analysis when the microstructure is known. In this research, the deformation behaviour and fracture characteristics of a spinodal decomposed copper alloy at various ageing conditions have been investigated thoroughly. Systematic changes in microstructure are implemented in this alloy through the alteration of ageing time at an elevated temperature on different specimens. As a result, the wavelength and amplitude of modulated spinodal structures have been varied, while those of initial inclusion content, other second phase particles' volume/distribution, initial crystallographic texture and grain size were kept unaltered. Spinodal decomposition results from the coherency strains, hence the zone of mismatch of strain/stress between phases/interfaces acts as micro/nano void nucleation sites under tensile deformation. The two-dimensional tensile were correlated with the deformation and fracture properties of the alloy under constant strain rate at different ageing conditions at ambient environment. The results obtained bring fractographic information to the mechanical engineers and nuclear scientists investigating ductile fracture of spinodal decomposed alloys. This is a novel technique to characterise the material from an analysis of the fracture surface features.

KEYWORDS:

• Ductile fracture
• fractography
• spinodal decomposition
• ageing
• image processing
• copper alloys

Acknowledgements

The authors would also like to thank Professor Laurent Pizzagalli (The Editor – Philosophical Magazine) for the provision of facilities for the revision of the manuscript. The insightful suggestions, comments and strong recommendations about the manuscript by the anonymous reviewers are also gratefully appreciated.

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Arpan Das http://orcid.org/https://orcid.org/0000-0003-1822-0135

Chandra Bhanu Basak http://orcid.org/https://orcid.org/0000-0001-6334-1003