Microstructure and Mechanical Properties of Ultrasonic Welded Joint of 1060 Aluminum Alloy and T2 Pure Copper

The Cu/Al dissimilar joint, welded by high-power ultrasonic welding technology, is still facing challenges despite the significant research attention it has attracted. In this work, the microstructure and mechanical properties of resistance heat-assisted high-power ultrasonic welding of Cu/Al are investigated, in order to obtain high-quality joints. The intermetallic compound (IMC) at the interface of hybrid welding is primarily composed of Al2Cu, and the additional resistance of heat reduces the thickness of this brittle IMC layer. The average shear stress for the joint prepared by hybrid welding is~97 MPa, which is higher compared to the joint strength without resistance heat (90 MPa). Moreover, the duration of the hybrid welding process is shorter. Finally, the fracture of the hybrid weld is found to be a brittle-ductile hybrid mode.

Section: The Average Shear Stressmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Microstructure and Mechanical Properties of Resistance Heat-Assisted High-Power Ultrasonic Dissimilar Welded Cu/Al Joint

Biao

2019

“…Figure 8 shows the load-depth (P-h) curves and their corresponding indentations. As shown in Figure 8a, the P-h was divided into different stages in accordance with the load change [35][36][37]. The first stage was the loading stage before the maximum indentation load was reached.…”

Section: Nanoindentation Characterizationmentioning

confidence: 99%

Interface Microstructure and Nanoindentation Characterization of Laser Offset Welded 5052 Aluminum to Press-Hardened Steel Using a Brass Interlayer

Zhou

Luo

et al. 2019

Laser offset welding of 5052 aluminum to press-hardened steel using a brass interlayer was carried out. The cross-sectioned macrostructure and tensile strength were governed by varying the thickness of the brass interlayer. The maximum tensile strength reached 56.4 MPa when the thickness of brass interlayer was 0.05 mm. Subsequently, the interface microstructure, the nanoindentation characterization, and the fracture behavior were evaluated experimentally by means of scanning electron microscopy (SEM), energy-dispersive X-ray spectrometer (EDS), and micro-X-ray diffraction (micro-XRD), respectively. It was found that the intermetallic compound (IMC) layer at the interface consisted of an Fe2Al5 layer and an FeAl layer, and the estimated nanohardness of Fe2Al5, FeAl, and Fe3Al were 16.11 GPa, 9.48 GPa, and 4.13 GPa, respectively. The fracture of the joint with the 0.05 mm brass interlayer was a mixture of cleavage fracture and intergranular fracture, while that of the joint with the 0.1 mm brass interlayer exhibited the characterization of a major dendrite arm, leaving a metallurgical connected zone consisting of the Al2Cu and the α-Al phase.

“…For example, the batteries of electric vehicles require a high number of Cu/Al connections, and the hydrometallurgical cathode plates require Cu/Al composite conductive heads. However, some physical properties of these materials are markedly different, which makes it difficult to weld Al to Cu effectively [5,6]. Furthermore, Cu and Al are relatively negative metals, and they have good intermiscibility [7].…”

Section: Introductionmentioning

confidence: 99%

The Interfacial Characterization and Performance of Cu/Al-Conductive Heads Processed by Explosion Welding, Cold Pressure Welding, and Solid-Liquid Casting

Wei

Sun³

et al. 2019

The Cu/Al composites conductive head is widely used in hydrometallurgy as the core component of cathode plate. Its conductive properties directly affect the power consumption, and the bonding strength and corrosion resistance determine the conductive head service life. The Cu/Al conductive head prepared by explosion welding, cold pressure welding, and solid-liquid casting methods were investigated in this paper. The interface microstructure and compositions were examined by scanning electron microscope and X-ray energy dispersive spectrometry. The bonding strength, interface conductivity, and the corrosion resistance of three types of joints were characterized. The Cu/Al bonding interface produced by explosive welding presented a wavy-like morphology with typical defects and many of brittle compounds. A micro-interlocking effect was caused by the sawtooth structures on the cold pressure welding interface, and there was no typical metallurgical reaction on the interface. The Cu/Al bonding interface prepared by solid-liquid casting consisted mainly of an Al-Cu eutectic microstructure (Al2Cu+Al) and partial white slag inclusion. The thickness of the interface transition layer was about 200–250 µm, with defects such as holes, cracks, and unwelded areas. The conductivity, interfacial bonding strength, and corrosion resistance of the conductive head prepared by explosive welding were superior to the other two.