TY - JOUR
T1 - Interfacial bonding mechanism and mechanical properties of micro friction stir blind riveting for multiple Cu/Al ultra-thin layers
AU - Khan, Haris Ali
AU - Wang, Kaifeng
AU - Li, Jingjing
N1 - Funding Information:
The authors acknowledge US National Science Foundation Civil, Mechanical and Manufacturing Innovation Grants No. 1664377 and 1651024 .
Publisher Copyright:
© 2018 Elsevier Inc.
PY - 2018/7
Y1 - 2018/7
N2 - In this research, bonding mechanisms and mechanical properties were investigated for a newly developed multilayer dissimilar material joining technique, micro friction stir blind riveting (viz. μFSBR), where the multilayer micro joint was made consisting of one Cu layer and three Al layers (each layer having 0.203 mm thickness) connected through Al rivet. Different microscopy techniques were employed (i.e. scanning electron microscopy and transmission electron microscopy) to unearth the bonding mechanisms of the three interfaces (i.e. Al rivet and Cu sheet interface, Cu sheet and Al sheet interface, and Al rivet and Al sheet interface) which revealed intricate yet distinct bonding phenomenon for each interface. A nano-scale diffusion layer in addition to two-way material flow consequential heterogeneous lamellar structures and mechanical interlocking was formed at the Al rivet and Cu sheet interface; Cu particles diffused into a non-uniform thickness thin oxide layer at the Cu sheet and Al sheet interface; and Al sheet experienced grain refinement near the interface close to Al rivet with a nano-scale gap. These observations revealed that both mechanical and metallurgical bonding occurred simultaneously in μFSBR. The formation of different bonding mechanisms resulted in superior bonding strength and absorbed energy compared to conventional micro blind riveting joints, which was further confirmed through layer by layer tensile tests.
AB - In this research, bonding mechanisms and mechanical properties were investigated for a newly developed multilayer dissimilar material joining technique, micro friction stir blind riveting (viz. μFSBR), where the multilayer micro joint was made consisting of one Cu layer and three Al layers (each layer having 0.203 mm thickness) connected through Al rivet. Different microscopy techniques were employed (i.e. scanning electron microscopy and transmission electron microscopy) to unearth the bonding mechanisms of the three interfaces (i.e. Al rivet and Cu sheet interface, Cu sheet and Al sheet interface, and Al rivet and Al sheet interface) which revealed intricate yet distinct bonding phenomenon for each interface. A nano-scale diffusion layer in addition to two-way material flow consequential heterogeneous lamellar structures and mechanical interlocking was formed at the Al rivet and Cu sheet interface; Cu particles diffused into a non-uniform thickness thin oxide layer at the Cu sheet and Al sheet interface; and Al sheet experienced grain refinement near the interface close to Al rivet with a nano-scale gap. These observations revealed that both mechanical and metallurgical bonding occurred simultaneously in μFSBR. The formation of different bonding mechanisms resulted in superior bonding strength and absorbed energy compared to conventional micro blind riveting joints, which was further confirmed through layer by layer tensile tests.
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U2 - 10.1016/j.matchar.2018.04.032
DO - 10.1016/j.matchar.2018.04.032
M3 - Article
AN - SCOPUS:85046455086
SN - 1044-5803
VL - 141
SP - 32
EP - 40
JO - Materials Characterization
JF - Materials Characterization
ER -