CN-121972844-A - Composite welding method for connector cable

CN121972844ACN 121972844 ACN121972844 ACN 121972844ACN-121972844-A

Abstract

The invention discloses a compound welding method for a connector cable. The composite welding method comprises the steps of preprocessing a terminal and a conductor, enabling a surface to be connected to form a close contact or an accurate gap between the terminal and the conductor, applying pressure to a connecting area of the terminal and the conductor by adopting a shaping electrode, enabling a contact interface of the terminal and the conductor to be locally melted to form initial metallurgical bonding, scanning and irradiating laser beams on the initial bonding area formed by resistance welding along the outer side surface of the bonding area, enabling the local depth of the bonding area to be secondarily melted, achieving reinforcement and interface optimization of the initial bonding point, and cooling, cleaning and performance inspection of a connection point after welding is completed. The invention realizes the high continuity of the geometric and electrical characteristics of the connecting interface on the premise of no additional solder by the composite technology of resistance welding shaping positioning and laser welding micro-area reinforcement, thereby simultaneously obtaining ultra-low high frequency impedance fluctuation and extremely high mechanical connection strength.

Inventors

DENG LEI
Zang Chaoqiang
JIANG HAIHONG
LIU JUNZHONG
QI YIHONG

Assignees

珠海领翌科技有限公司

Dates

Publication Date: 20260505
Application Date: 20260203

Claims (10)

1. A method of composite welding of a connector cable, comprising: Pretreating a connector terminal and a cable conductor, and fixing the connector terminal and the cable conductor at a preset relative position to enable a surface to be connected to form close contact or an accurate gap; applying pressure to the fixed terminal and conductor connecting area by a pair of integral electrodes, and applying pulse current, and locally melting the contact interface of the terminal and the conductor by utilizing the Joule heat generated by the contact resistance to form initial metallurgical bonding, so as to complete mechanical positioning and initial electric connection; Scanning and irradiating the initial bonding area formed by resistance welding along the outer side surface of the bonding area by adopting a laser beam to enable the local depth of the bonding area to be fused for the second time, so as to realize the reinforcement and interface optimization of the initial bonding point; And cooling, cleaning and performance inspection are carried out on the connection point after welding is completed.
2. The method of composite soldering of a connector cable of claim 1 wherein the shaping electrode comprises a resistance welding press head and a resistance welding base, the resistance welding base is provided with a T-shaped bearing table, the terminal pad is placed on a surface of the bearing table near the resistance welding press head, the conductor is placed on the surface of the terminal pad in the middle, and the resistance welding press head presses the conductor to perform resistance welding on the terminal and the conductor.
3. The connector cable composite welding method according to claim 2, wherein the welding face of the resistance welding press head is provided with a groove so that the conductor is pressed in the groove, the width of the notch of the groove is in conformity with the width of the terminal pad, and the width of the groove is gradually reduced in the direction from the notch to the groove bottom so as to apply lateral extrusion to the conductor and guide plastic flow forming thereof.
4. The connector cable composite welding method according to claim 2, wherein the resistance welding press head and the resistance welding base are made of one material of tungsten copper alloy, chromium zirconium copper or dispersion-strengthened copper.
5. The method of claim 2, wherein during the resistance welding, a preset pressure is applied to the resistance welding head to stabilize the contact resistance, and then a pulse current with a preset waveform and magnitude is triggered, and the pressure is maintained for a period of time after the current is ended; And monitoring a dynamic resistance value or electrode displacement in the welding loop in real time, comparing the dynamic resistance value or electrode displacement with a preset standard curve, and judging and marking the abnormal welding if the deviation exceeds a threshold value.
6. The method of composite welding of connector cables according to claim 2, wherein after the end of the resistance welding, the resistance welding pressure head is removed, and the laser welding is continued on the carrying table under the inert gas protection atmosphere, wherein the diameter of the laser spot is smaller than or equal to the width of the resistance welding bonding area.
7. The connector cable composite welding method as in claim 6, wherein the laser welding power is dynamically adjusted during the laser welding based on the actual welding energy recorded during the resistance welding.
8. The connector cable composite welding method according to claim 1, wherein the pretreatment of the cable conductor includes: stripping the cable outer insulation layer to expose a conductor of a preset length; The exposed conductor surface is shaped to form a landing surface that conforms to the shape of the terminal pad.
9. The connector cable composite welding method according to claim 1, wherein the performance test of the connection point after the welding is completed includes: And carrying out characteristic impedance test on the welding point by using a time domain reflectometer under the bandwidth of at least 40GHz, wherein the test standard is that the absolute value of TDR impedance fluctuation caused by the welding point is less than or equal to 1 ohm.
10. The connector cable composite welding method according to claim 9, wherein the performance test of the connection point after the welding is completed further comprises: And (3) testing the axial pulling force of the welded single wire and terminal connection point through a tensile testing machine, wherein the maximum breaking force of the welding point is not lower than 6N.

Description

Composite welding method for connector cable Technical Field The invention relates to the technical field of high-speed and high-frequency interconnection, in particular to a compound welding method for a connector cable. Background With the rapid development of 5G communication, artificial intelligence, high performance computing and data center technologies, the demands for data communication rate and bandwidth have exponentially increased, pushing the operating frequency of high-speed electrical connectors to millimeter wave frequency bands (e.g., 40GHz, 56GHz, or even higher). In such high frequency applications, any minor discontinuity in the signal transmission path can cause severe signal reflection, attenuation and distortion. In the manufacture of high-speed connectors of the related art, the electrical connection between the connector terminals and the cable conductors (such as the core wires of a coaxial or twinaxial cable) is performed by a process of applying solder (e.g., hotbar solder) after crimping. Although the process can realize reliable electrical conduction and mechanical fixation, the inherent and difficult-to-overcome defects are exposed when the millimeter wave signal transmission is dealt with. The Hotbar soldering process must introduce additional tin-based solder. The solder is different from conductor materials such as copper in material and dielectric constant, and the filling shape and volume of the solder are difficult to accurately control, which is equivalent to introducing irregular and high-dielectric constant heterogeneous materials into a transmission path, so that the characteristic impedance at the connection point is suddenly changed and fluctuated. Time Domain Reflectometry (TDR) tests have shown that impedance fluctuations of up to 4 ohms or more at high frequencies become a bottleneck limiting signal rate rise. For welding, the conductors are usually stacked on end surfaces or overlapped on side surfaces, so that physical steps or sections are formed at the joints, smooth transition of the conductors is damaged, geometric structure of the signal transmission path is discontinuous, impedance change is caused, and undesired parasitic capacitance and inductance are generated. For low frequency or direct current applications, the above problems are acceptable. However, in the field of high frequency connectors, conventional soldering processes have been counter to the core design goals of high bandwidth, low loss, high signal integrity due to their inherent nature of introducing dissimilar materials, causing structural discontinuities. Disclosure of Invention The present invention aims to solve at least one of the technical problems in the related art to some extent. Therefore, the embodiment of the invention provides a compound welding method for a connector cable, which realizes high continuity of the geometric and electrical characteristics of a connection interface on the premise of no additional welding flux by a compound process of resistance welding shaping positioning and laser welding micro-area strengthening, thereby simultaneously obtaining ultralow high-frequency impedance fluctuation and extremely high mechanical connection strength. The compound welding method of the connector cable comprises the following steps: Pretreating a connector terminal and a cable conductor, and fixing the connector terminal and the cable conductor at a preset relative position to enable a surface to be connected to form close contact or an accurate gap; applying pressure to the fixed terminal and conductor connecting area by a pair of integral electrodes, and applying pulse current, and locally melting the contact interface of the terminal and the conductor by utilizing the Joule heat generated by the contact resistance to form initial metallurgical bonding, so as to complete mechanical positioning and initial electric connection; Scanning and irradiating the initial bonding area formed by resistance welding along the outer side surface of the bonding area by adopting a laser beam to enable the local depth of the bonding area to be fused for the second time, so as to realize the reinforcement and interface optimization of the initial bonding point; And cooling, cleaning and performance inspection are carried out on the connection point after welding is completed. In some embodiments, the shaping electrode comprises a resistance welding pressure head and a resistance welding base, a T-shaped bearing table is arranged on the resistance welding base, the terminal bonding pad is arranged on the surface of one side of the bearing table, which is close to the resistance welding pressure head, the conductor is arranged on the surface of the terminal bonding pad in the middle, and the resistance welding pressure head presses the conductor to perform resistance welding on the terminal and the conductor. In some embodiments, the welding surface of the resistance welding press head is pr