Open-cell copper foam joining: joint strength and interfacial behaviour

Abstract

A copper (Cu) foam was brazed with Cu-4.0Sn-9.9Ni-7.8P filler foil for joint strength and interface analysis. Brazed 50 pores per inch (PPI) Cu foam yielded a maximum compressive strength of 14.4 MPa with a 127% increment compared to nonbrazed Cu foam. 15 PPI Cu foam produced a maximum shear strength of 2.7 MPa. Scanning electron microscopy showed that the thickness of the brazed seam decreased with increasing the Cu foam’s PPI. The formation of the Cu, Cu₃P (P: phosphorus) and Ni₃P (Ni: nickel) at the Cu/Cu foam interface was validated using energy-dispersive X-ray spectroscopy (EDX) and X-ray diffraction. EDX line scanning analysis revealed the diffusion of P and Ni into Cu foam, which took place via capillary force action.

KEYWORDS:

• Brazing
• compressive
• intermetallic
• shear
• porous metal
• microstructure
• diffusion
• filler foil

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Nur Amirah Mohd Zahri http://orcid.org/0000-0002-7544-7195

Farazila Yusof http://orcid.org/0000-0001-6034-0996

Additional information

Funding

This work was supported by the Fundamental Research Grant Scheme, FRGS University of Malaya, under [Project number FP062-2015A] and Research Universities, RU University of Malaya, under [Project number ST006-2018].