Recrystallization Behavior of a Pure Cu Connection Interface with Ultrasonic Welding

Abstract

Three-dimensional metal waveguide components are key components in the next generation of radio telescopes. Ultrasonic additive manufacturing technology combining ultrasonic welding and micro electrical discharge machining (micro-EDM) provides a new method for the overall manufacturing of waveguide elements, and the effective welding of Electrolytic Tough Pitch copper (Cu-ETP) sheets is the key process of this method. This study demonstrates that the orthogonal test optimization method is used to conduct ultrasonic welding tests on Cu-ETP. Specifically, electron backscattered diffraction (EBSD) technology is used to analyze the crystal grains, grain boundary types and texture changes during interface recrystallization. In addition, the finite element software ABAQUS 6.13 is employed to calculate the temperature field in order to determine the possibility of recrystallization of the welding interface. The results showed that the average grain size of the welding interface decreased from 20 to 1~2 μm. The Cu-ETP matrix is mainly composed of coarse grains with high-angle grain boundaries (HAGBs), while a large number of low-angle grain boundaries (LAGBs), subcrystals and fine equiaxed grains appear in the welded joint. At the same time, discontinuous dynamic recrystallization (DDRX) occurs in the less strained area, and continuous dynamic recrystallization (CDRX) is predominant in the greater strain area. The temperature field calculation shows that the peak temperature of the welding interface exceeds the recrystallization temperature of Cu-ETP from 379.05 to 433.2 °C.

Ultrasonic Welding of Nickel with Coarse and Ultrafine Grained Structures

“…To elucidate the nature of this effect, the fracture Our study has shown that the strength of weld joints non-monotonically depends on the clamping force. This behavior is typical for USW and has been observed, for example, on similar Cu-Cu and dissimilar Al-Cu joints [30,31]. The increase in strength with increasing P is usually explained by an increase in the bonded area in the contact zone.…”

“…Such structural changes are typical of non-uniformly deformed metals. A fine-grained layer is formed as a result of dynamic recrystallization near the contact surface of the welded specimens, where the magnitude of deformation and temperature have the highest values [30,38]. With increasing distance from the contact surface, the strain rapidly decreases, and the processes of dynamic recovery prevail, which leads to the formation of a developed LAB network.…”

Evaluasi Laju Pengelasan terhadap Mikrostruktur Sambungan Aluminium 5052 dengan menggunakan Metode Friction Stir Welding

“…Selama proses FSW akan terbentuk heat affected zone (HAZ), thermomechanical affected zone (TMAZ), dan daerah adukan las (weld nugget) [4]. Temperatur yang terjadi pada proses FSW berada di bawah temperatur leleh logam induk sehingga temperatur rekristalisasi akan berbeda dengan pengelasan konvensional [5]- [7]. HAZ yang terbentuk pada FZW mirip dengan las konvensional karena karena zona ini tidak mengalami deformasi.…”

Factors affecting evolutions of contact area formation and bonding strength in pure Cu/Cu joints produced by ultrasonic spot welding

“…At the joint interface, the bonding area originates from sliding contact between base metals. As more contact areas are produced, a higher fraction of the surface metal is involved in the development of bonding areas due to bonding mechanisms such as local plastic deformation [15], surface wear [16], phase transformation [17] and dynamic recrystallisation [18][19][20].…”