基于铜环驱动的核电用锆合金-不锈钢电磁脉冲焊接研究OA

The composite components of zirconium alloy(Zr)and stainless steel(SS)hold significant application potential in the nuclear power.However,both materials exhibit weak conductivity and limited deformability,making it hard to form a metallurgical bonding directly by using conventional electromagnetic pulse welding(EMPW).This work proposes a method employing a copper(Cu)ring to drive the high-speed movement of Zr tube,thereby enabling the high-speed collision and reliable connection between Zr tube and SS rod. Firstly,the basic principle of EMPW of Zr tube and SS rod driven by Cu ring,the processes including the deformation of Cu ring,the driver-induced deformation of Zr tube,and the high-speed collision between Zr tube and SS rod are analyzed.The three-dimensional model of EMPW of Zr tube and SS rod is established in COMSOL software.The circuit,magnetic field,and structural field module is coupled to simulate the magnetic flux density,induced eddy current,and electromagnetic force distribution and the movement behavior of the Cu ring and Zr tube.The EMPW platform of Zr tube and SS rod is built by the self-made EMPW equipment WD-28.Then,the Zr-3 tube-SS 304 rod EMPW experiment based on Cu ring is carried out.Finally,the mechanical property of the joint is tested by a tensile testing machine.The microstructure and elemental distribution of the joint are also analyzed by scanning electron microscope(SEM)and energy dispersive spectrometer(EDS). The simulation results show that the magnetic flux density of the Cu ring in the welding process is consistent with that of Zr tube without driving,but the Cu ring forms a shielding effect on the Zr tube.The induced eddy current generated by the Cu ring is larger than that of the Zr tube without Cu ring.The electromagnetic force of the Cu ring is higher than that of the Zr tube without Cu ring.Under the action of electromagnetic force,the Cu ring collides with the Zr tube,achieving energy transfer.For a period of time after the collision,the velocity of the Zr tube is higher than that of the Cu ring.The Cu ring is continues accelerated by the electromagnetic force,driving the Zr tube to collide with the SS rod at high speed.The collision velocity between Zr tube and SS rod driven by Cu ring is higher than that without driving,but the collision angle is almost the same.The experiments results show that when the discharge voltage is 11 kV and the welding gap is 1.5 mm,the joint of Zr tube and SS rod is obtained under the drive of Cu ring.When the load reached 12.080 kN,the Zr tube break without damaging of the joint.There are flat structures,wavy structures and the vortex structures at the EMPW interface,and the elements have diffused at the interface. In this work,the EMPW of Zr tube and SS rod was successfully achieved through the method of Cu ring drive.The following conclusions can be drawn:(1)The initial velocity provided by the Cu ring for the Zr tube should be greater than the minimum collision velocity required to generate a metal jet between the Zr tube and the SS rod,as well as the minimum velocity required to overcome deformation and collision of the Zr tube.(2)The magnetic flux density,induced eddy current and electromagnetic force of the Zr tube without driving are much smaller than those on the Cu ring when it is driven.Under the action of the Cu ring,the collision velocity between the Zr tube and the SS rod increases.There are multiple collision processes between the two,and the collision angle is almost the same as without driving.(3)Under the conditions of this work,there was no collision between the Zr tube and the SS rod without driving,while the metallurgical bonding between the Zr tube and the SS rod based on Cu ring driving was achieved mainly through mechanical interlocking and element diffusion,and reliable connection between the Zr tube and the SS rod achieved.This work could expand the application scope of EMPW technology and contribute to advancing the manufacturing capabilities of nuclear power equipment in China.