Interface characteristics and mechanical behavior of Cu/Al clad plate produced by the corrugated rolling technique
Introduction
Cu/Al clad plates have attracted much interest owing to the excellent properties associated with light quality, high thermal and electrical conductivity in recent years [1]. They are frequently used for transfer pipes, conductor wires, power cables and armor protection [[2], [3], [4], [5], [6]]. Now, many methods have been introduced to prepare Cu/Al clad plates, such as roll bonding [2,7,8], diffusion bonding [9], and explosive-welded [10,11]. Among all these methods mentioned above, the roll bonding method is commonly employed because of stable product quality, low-cost and mass production [[12], [13], [14], [15]].
The influence factors of Cu/Al plates by cold rolling under large reduction ratio and the interface structure and fracture mechanism had been analyzed, showing that the intermetallic compounds (CuAl2, CuAl, Cu9Al4, and Cu4Al3) promoted creaks propagation and weakened the bond strength and the fracture mechanism transformed from ductile to brittle cleavage [16]. The deformation characteristic of Cu/Al plate during the rolling process under different parameters was researched, obtaining the plastic deformation characteristics under various technological parameters (including initial thickness ratio, reduction ratio, deformation rate, etc.) [17]. The superiority of asymmetric roll bonding was qualitatively expressed by the stress state of the deformation zone [18]. Their researches showed that the asymmetric roll can lead to severe shear deformation for clad plates, which provided a good interface during annealing process. In comparison with the traditional rolled plates, the strengthening of asymmetrical rolled plates resulted from the improved interfacial microstructure. Although the preparation of Cu/Al clad plate by roll bonding has become very common, low bonding strength is also the problem in Cu/Al plates.
In recent years, inhomogeneous plastic deformation was introduced to improve the mechanical properties of light alloys. AA5083 alloy forming process was introduced by using different corrugation dies profile (V groove, flat groove and semi-circular) and the effect of repetitive corrugation and straightening (RCS) on grain refinement was analyzed, showing that an average grain size of ∼20 μm was observed in both the flat groove and the semi-circular dies [19]. The influence of the RCS process on the grain size of Al-3Mg-0.25Sc alloy was discussed through 8 passes at room temperature [20]. Their results displayed that this procedure introduced significant grain refinement with an average grain size of ∼0.6−0.7 μm.
Up to now, the deformation process of the corrugated sheets is still limited to single metal alloy, however, there are a few studies on rolling clad plates with corrugated rollers. Based on the corrugated technique, the corrugated + flat rolling (CFR) process was put forward to produce bimetal composite plates. In the prior article [21], flat Cu/Al clad plates had been produced by this process under a low reduction ratio of 20 % at room temperature. It was concluded that the corrugated interface was formed without intermetallic compounds and the interfacial grain refinement occurred. Meanwhile, Mg/Al clad plates were manufactured by CFR process and the microstructure characterization and mechanical property were measured [22]. It was concluded that spatial distribution was observed for the grain along both the normal and rolling directions for AZ31B Mg alloy and the transverse tensile strength was much higher than the rolling tensile strength.
The contents of the previous paper mentioned above are about the interface characteristics and tensile properties of the flat clad plate after the second flat pass, and the microstructure and mechanical behavior of the corrugated clad plate only after the first corrugated pass process are not studied in detail. During the CFR process, corrugated Cu/Al clad plate made by the corrugated rolling can be used as an intermediate product, or as a final product in aircraft seatback, armor protection, and other aspects to meet the needs of customers. Previous corrugated plates were mostly extruded by abrasive tools [20,23]. While the purpose of this study is to manufacture the corrugated Cu/Al clad plates by a simple and efficient rolling method for the extensive application.
Section snippets
Experimental
T2 copper (99.98 wt.% Cu + Ag, 0.001 wt.% Bi, 0.005 wt.% Fe, 0.002 wt.% As, 0.002 wt.% Sb, 0.005 wt.% Pb, 0.005 wt.% S) and 1060 aluminum (99.62 wt.% Al, 0.05 wt.% Si, 0.22 wt.% Fe, 0.03 wt.% Mg, 0.05 wt.% Zn, 0.03 wt.% Mn) were obtained as starting materials in this study. The dimensions of Cu and Al were 100 × 50 × 3 mm3 and 100 × 50 × 7 mm3, respectively. Before rolling, the initial materials were ground with wire brush until fresh metals leak out. And then, the surfaces were repeatedly
SEM analysis
Fig. 3 displays the SEM images and EDS line scan results of near-interface regions at various interfacial positions on the RD-ND plane. For the corrugated sample, the interfaces both peak and trough positions are tightly bonded. Furthermore, it can be seen that the Cu/Al bonding interface appears to be wavy, rather than a straight line. At the same time, the concentration of the Al element rapid declines from Al side to Cu side while the concentration distribution of the Cu element presents the
Interface microstructure
Fig. 3, Fig. 4 show that the well-bonded interfaces of the corrugated clad plate are obtained. Meanwhile, Fig. 4 presents that the grains near the interface are finer than that far away from the interface, especially at the trough position. The higher grain refinement efficiency in Cu side and Al side during plastic deformation is attributed to large local deformation induced by the corrugated roller. Such finer grains can contribute to a higher bonding strength owing to the fine grain
Conclusions
- (1)
Corrugated Cu/Al clad plate was obtained by the corrugated rolling process at the 50 % reduction ratio. The grain size at the Cu/Al interface was refined significantly, especially the trough position, because of the asymmetrical shear strain induced by the corrugated roller.
- (2)
Due to the plastic deformation during the rolling process, relatively low intensity gauss texture appears in the Cu and Al matrixes both at peak and trough positions. Furthermore, for metal Cu, the proportion of LAGBs at the
Declaration of Competing Interest
The authors report no declarations of interest.
Acknowledgments
This project is supported by Major Program of National Natural Science Foundation of China (U1710254), National Natural Science Foundation of China(51975398, 51904205, 51804215), Shanxi Province Science and Technology major projects (MC2016-01,20181101008), Natural Science Foundation of Shanxi Province (201801D221221), Key Projects of Shanxi Province Key Research and Development Plan(201703D111003), and the China Postdoctoral Science Foundation(2018M641680, 2018M641681).
References (41)
- et al.
Bonding behavior during cold roll-cladding of tri-layered Al/brass/Al composite
J Manuf Process
(2016) - et al.
Mechanical properties and tensile fracture mechanism investigation of Al/Cu/Ti/Cu/Al laminated composites fabricated by rolling
J Alloys Compd
(2019) - et al.
Welding parameters analysis and microstructural evolution of dissimilar joints in Al/Bronze processed by friction stir welding and their effect on engineering tensile behavior
Mater Sci Eng A
(2017) - et al.
Influence of reduction ratio on the interface microstructure and mechanical properties of roll-bonded Al/Cu sheets
Mater Sci Eng A
(2013) - et al.
Effect of heat treatment on bonding mechanism and mechanical properties of high strength Cu/Al/Cu clad composite
J Alloys Compd
(2019) Texture development in the interfacial zone of Al/Cu bimetal cold roll-bonded for E-mobility
Mater Lett
(2019)- et al.
Investigation of cold rolling influence on the mechanical properties of explosive-welded Al/Cu bimetal
Mater Sci Eng A
(2012) - et al.
Investigation of annealing treatment on the interfacial properties of explosive-welded Al/Cu/Al multilayer
Mater Des
(2012) - et al.
Preparation and properties for Ti/Al clad plates generated by differential temperature rolling
J Mater Process Technol
(2017) - et al.
Microstructural and textural evolutions in multilayered Ti/Cu composites processed by accumulative roll bonding
J Mater Sci Technol
(2019)
Microstructures and mechanical properties of Al/Mg Alloy multilayered composites produced by accumulative roll bonding
J Mater Sci Technol
Preparation, microstructure and mechanical properties of CP-Ti/AA6061-Al laminated composites by differential temperature rolling with induction heating
J Manuf Process
Interface strengthening of laminated composite produced by asymmetrical roll bonding
Mater Sci Eng A
Effects of die profile on grain refinement in Al–Mg alloy processed by repetitive corrugation and straightening
Mater Sci Eng A
A comparison of repetitive corrugation and straightening and high-pressure torsion using an Al-Mg-Sc alloy
JMR&T
A novel approach for preparing Cu/Al laminated composite based on corrugated roll
Mater Lett
Achieving a weak basal texture in a Mg–6Al–3Sn alloy by wave-shaped die rolling
Mater Des
Mechanism of warm and cold roll bonding of aluminum alloy strips
Mater Des
Impact of temperature on shear strength of single lap Al–Cu bimetallic joint
Compos Part B-Eng
Deformation behavior and crack propagation on interface of Al/Cu laminated composites in uniaxial tensile test
Rare Metals
Cited by (17)
Deformation behavior and microstructure formation mechanism at the interface of Mg/Al composite plate during vibration assisted rolling process
2023, Journal of Materials Processing TechnologyEffect of differential temperature on the interfacial microstructure evolution and mechanical properties of asymmetrically rolled Mg/Al composite plates
2023, Journal of Materials Research and TechnologyThe effect of interface orientation on deformation behavior of Cu/Al multilayer during tensile process
2023, Materials Today CommunicationsCitation Excerpt :Zhou et al. [22] investigated the strengthening mechanism of Cu/Al multilayers prepared by magnetron sputtering, and pointed that the interface exhibits (111) orientation relationship and semi-coherent interface assists to improve interface hardness and strength. Li et al. [23] investigated the interface characteristics and mechanical behavior of Cu/Al clad plate produced by corrugated rolling technique, and reported that the strength of clad plate is improved due to grain refinement and corrugated-shape interface. Wang et al. [24] investigated the effect of rolling parameters on the formability performance of Cu/Al composites, and revealed that a suitable deformation temperature and an increase in first-pass deformation are both conducive to enhance bimetallic deformation coordination.
The effect of loading axes on deformation behavior of Cu/Al multilayer
2023, Physics Letters, Section A: General, Atomic and Solid State PhysicsCitation Excerpt :Zhou et al. [17] studied the effect of compression direction on mechanical properties of explosively-welded Al/Cu pipe, and pointed that strength in parallel compression is higher than that in perpendicular compression. Li et al. [18] studied interface characteristics and mechanical behavior of Cu/Al clad plate prepared by corrugated rolling technique, and reported that corrugated interface is formed without intermetallic compounds and the strength of clad plate is improved. Zhang et al. [19] investigated fracture behavior of Al/Cu/Ti/Cu/Al laminated composites fabricated by rolling, and pointed that crack initiated and propagated at Al/Cu interface due to the weak interface bonding strength and different plastic deformation capacity of two layers.