Welding method for leg wire and chip of electronic detonator

Abstract

The invention discloses a welding method for an electronic detonator leg wire and a chip, which comprises the following steps: determining the characteristics of a welding material based on the types, thicknesses and sizes of the electronic detonator leg wire and the chip; laser welding parameters are determined according to the characteristics of the welding material; the laser welding parameters comprise at least one of laser power, pulse frequency, pulse width and welding speed; according to the characteristics of the welding material and the laser welding parameters, the laser action duration is determined; and based on the laser action duration, controlling a laser generator to weld the electronic detonator leg wire and the welding leg point of the chip. According to the welding method for the electronic detonator leg wire and the chip, the acting duration of the laser on the welding leg point of the electronic detonator leg wire and the chip is determined according to the characteristics of the welding material and the laser welding parameters, accurate control over the laser welding process parameters is achieved, and the mechanical strength and the signal transmission stability of the welding point are effectively improved.

Description

Technical Field

[0001] This application belongs to the field of electronic detonator manufacturing technology, and more specifically, relates to a method for welding electronic detonator leads to chips. Background Technology

[0002] Intelligent manufacturing plays a vital role in improving the safety level and core competitiveness of civil explosives enterprises. Electronic detonators, as high-precision and high-reliability detonation devices, enable remote and precise control of detonation time by welding the detonator leads to a chip integrating detonation control and safety protection circuits.

[0003] Traditional connection methods primarily employ soldering and thermoforming. However, these methods suffer from insufficient mechanical strength at the connection points, leading to breakage, poor contact, or unstable signal transmission, potentially causing accidental detonation or failure to detonate. To address these issues, some companies have begun researching laser welding to connect the leads and chips of electronic detonators. Laser welding technology offers advantages such as high welding speed, high quality, and a small heat-affected zone. However, the precision of laser welding is affected by factors such as laser beam focusing, material properties, and welding speed, making it difficult to completely control the position and size of the welding point and the welding duration. Furthermore, electronic detonators and chips typically utilize multiple materials, requiring the selection of appropriate laser parameters and welding processes to ensure material compatibility and weld quality.

[0004] Therefore, optimizing the process parameters for laser welding of electronic detonator leads and chips, and improving the reliability of laser welding technology in electronic detonator welding applications, is an urgent problem to be solved in order to achieve automated, continuous, safe, and intelligent production of industrial digital electronic detonator assembly. Summary of the Invention

[0005] The objective of this application is to provide a method for welding electronic detonator leads to chips, thereby optimizing the process parameters for laser welding of electronic detonator leads to chips and improving the reliability of laser welding technology in electronic detonator welding applications.

[0006] To achieve the above-mentioned technical effects, this application provides a method for welding electronic detonator leads to a chip, comprising: determining the characteristics of a welding material based on the type, thickness, and size of the electronic detonator leads and the chip; determining laser welding parameters according to the characteristics of the welding material; the laser welding parameters including at least one of laser power, pulse frequency, pulse width, and welding speed; determining the laser action duration according to the characteristics of the welding material and the laser welding parameters; and controlling a laser generator to weld the solder joints of the electronic detonator leads and the chip based on the laser action duration.

[0007] This solution determines laser welding parameters based on the specifications of the electronic detonator leads and chips, as well as the characteristics of the welding materials. This makes the welding process more targeted, helps reduce the heat-affected zone, minimizes the impact on the detonation circuit on the chip, and ensures welding quality and efficiency. The laser irradiation time is determined according to the characteristics of the welding materials and the laser welding parameters. Based on this time, the laser generator is controlled to weld the solder joints of the electronic detonator leads and chips, helping to avoid over-soldering or under-soldering, further improving the precision and consistency of the welding between the electronic detonator leads and the chip.

[0008] As an improvement to the technical solution of this application, the step of determining the laser action duration based on the characteristics of the welding material and the laser welding parameters includes: determining the welding energy required per unit length of weld joint based on the characteristics of the welding material; and determining the laser action duration based on the welding energy and the laser welding parameters.

[0009] Furthermore, the welding energy is determined according to the following formula: in, It is the laser energy loss coefficient, and L is the length or diameter of the solder joint. It is the density of the welding material, It is the specific heat capacity of welding materials, It is the melting point of the welding material. The initial temperature of the solder joint, It is the cross-sectional area of ​​the weld joint.

[0010] Furthermore, the laser generator is in continuous laser mode; the laser duration is determined according to the following formula: in, The welding energy, The laser power, This refers to the welding speed.

[0011] Furthermore, the laser generator is a pulsed laser; the laser duration is determined according to the following formula: in, The welding energy, The laser power, The pulse frequency, It is the pulse width.

[0012] As an improvement to the technical solution of this application, the step of controlling the laser generator to weld the solder joints of the electronic detonator pins and the chip based on the laser action duration includes: real-time monitoring of the welding area of ​​each solder joint, and adjusting the laser action duration according to the monitoring data; the monitoring data includes the temperature of the solder joint and the range of the heat-affected zone; and controlling the laser generator to weld the solder joints of the electronic detonator pins and the chip based on the adjusted laser action duration.

[0013] As an improvement to the technical solution of this application, the welding process is carried out under inert gas protection.

[0014] The beneficial effects of this application are as follows: The proposed solution determines laser welding parameters based on the specifications of the electronic detonator leads and chip, as well as the characteristics of the welding materials. This makes the welding process more targeted, helps reduce the heat-affected zone, minimizes the impact on the detonation circuit on the chip, and ensures welding quality and efficiency. The laser application time is determined according to the characteristics of the welding materials and the laser welding parameters. Based on this time, the laser generator is controlled to weld the solder joints of the electronic detonator leads and chip, helping to avoid over-soldering or under-soldering, further improving the precision and consistency of the welding between the electronic detonator leads and the chip. Attached Figure Description

[0015] Figure 1 This is a schematic flowchart illustrating a method for soldering electronic detonator leads to a chip in an embodiment of this application. Detailed Implementation

[0016] The embodiments of the technical solution of this application will be described in detail below. The following embodiments are only used to more clearly illustrate the technical solution of this application, and are therefore merely examples and should not be used to limit the scope of protection of this application. Furthermore, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0017] Figure 1 This is a schematic flowchart illustrating a method for soldering electronic detonator leads to a chip, as described in an embodiment of this application. Figure 1 As shown, the soldering method between the electronic detonator leads and the chip in this embodiment includes the following steps: S1: Determine the characteristics of the welding material based on the type, thickness, and size of the electronic detonator leads and chip; Specifically, the characteristics of the welding material determined in this step are those that directly affect heat conduction and the size of the heat-affected zone during the welding process. These characteristics include, but are not limited to, at least one of the following: density, melting point, specific heat capacity, thermal conductivity, and coefficient of thermal expansion.

[0018] Alternatively, when selecting welding materials, the following principles can be followed: select welding materials with thermal conductivity or coefficient of thermal expansion similar to those of the electronic detonator leads and chip materials to reduce welding stress and avoid cracking; the melting point of the welding material should be slightly lower than that of the electronic detonator leads and chip to ensure that the material can melt and form a strong weld joint during the welding process, while avoiding thermal damage to the electronic detonator leads and chip.

[0019] S2: Determine the laser welding parameters based on the characteristics of the welding material; Specifically, the laser welding parameters include at least one of laser power, pulse frequency, pulse width, and welding speed. Based on the characteristics of the welding material, a welding material whose characteristics are closest to those of the material is selected. The welding material's response to heat can be evaluated based on its density, melting point, specific heat capacity, and thermal conductivity, as determined in step 1. Based on the thermal characteristics of the welding material, the most suitable laser welding parameters are selected. For example, if the welding material has a low melting point, a lower laser power and a shorter pulse width can be selected to avoid over-melting. The laser welding parameters are adjusted according to the strength and welding quality requirements of the weld joint. For example, if a higher weld joint strength is required, it may be necessary to increase the laser power and pulse width.

[0020] S3: Determine the laser treatment duration based on the characteristics of the welding material and the laser welding parameters; The laser irradiation duration is the time the laser beam irradiates the weld joint. This duration directly determines the energy input to the welding area; too short a duration leads to insufficient welding (under-welding), while too long a duration leads to overheating, ablation, or an excessively large heat-affected zone (over-welding). Therefore, calculating the laser irradiation duration is crucial for ensuring weld quality.

[0021] In one implementation, this step also includes the following sub-steps: S31: Determine the welding energy required per unit length of weld joint based on the characteristics of the welding material; In one implementation, the welding energy is determined according to the following formula (1): (1) in, It is the laser energy loss coefficient, and L is the length or diameter of the solder joint. It is the density of the welding material, It is the specific heat capacity of welding materials, It is the melting point of the welding material. The initial temperature of the solder joint, It is the cross-sectional area of ​​the weld joint.

[0022] It should be noted that during the actual welding process, some laser energy will be reflected, absorbed, or lost, therefore the energy loss coefficient η needs to be considered. The value of η is usually between 0 and 1, and the specific value depends on factors such as the reflectivity of the material and the laser wavelength. After multiple experiments, this energy loss coefficient has been stabilized at 0.2~0.4.

[0023] S32: Determine the laser action duration based on the welding energy and the optical welding parameters.

[0024] Specifically, when selecting a laser welding mode, it is necessary to choose the appropriate laser mode and parameters based on the specific welding requirements and material properties. For example, for heat-sensitive materials, a pulsed laser mode is usually selected to reduce the heat-affected zone; for applications requiring high-efficiency welding, a continuous laser mode can be selected.

[0025] In one implementation, the laser generator is in continuous laser mode; the duration of the laser action is determined according to the following formula (2): (2) in, The welding energy, The laser power, This refers to the welding speed.

[0026] In one implementation, the laser generator is in pulsed laser mode; the duration of the laser action is determined according to the following formula: (3) in, The welding energy, The laser power, The pulse frequency, It is the pulse width.

[0027] S4: Based on the laser action duration, control the laser generator to weld the electronic detonator leads and the chip's solder joints.

[0028] In one implementation, this step also includes the following sub-steps: The welding area of ​​each of the aforementioned solder joints is monitored in real time, and the laser treatment duration is adjusted based on the monitoring data; the monitoring data includes the temperature of the solder joint and the range of the heat-affected zone. Based on the adjusted laser action duration, the laser generator is controlled to weld the electronic detonator leads and the chip's solder joints.

[0029] Preferably, to improve welding quality, specially designed clamps should be used to fix the electronic detonator chip and lead wires to ensure that they remain in the correct position during the welding process.

[0030] Preferably, the welding process is performed under inert gas protection. Using an inert gas such as nitrogen or helium to protect the welding area prevents oxidation of the weld beads. The flow rate and pressure of the inert gas should be adjusted according to the size of the welding area and the laser power to ensure that the welding area is completely covered by the inert gas.

[0031] Example 1 The following process parameters are used for soldering copper electronic detonator leads with a diameter of 0.2 mm and a length of 1 mm, and gold-plated aluminum chip pads with an aluminum layer thickness of 0.1 mm, a gold layer thickness of 0.01 mm, and a pad diameter of 0.3 mm: Soldering material: Tin-lead alloy (Sn63Pb37); Characteristics of welding materials: density ρ_SnPb=8500kg / m³, specific heat capacity c_SnPb=150J / (kg·K), melting point T_m_SnPb=183°C, thermal conductivity 50W / (m·K); Initial temperature: T_0 = 25°C; Solder pad length: L = 0.3mm (based on pad diameter); Cross-sectional area of ​​the weld joint: A = π * (0.3 mm / 2)² = 0.0707 mm² = 7.07 * 10⁻⁸ m²; Laser energy loss coefficient: η = 0.3; Laser mode: Continuous laser mode; Laser power: P=7W; Welding speed: v = 2 mm / s; Welding energy E = 0.91 * 10^-6 J; Laser action duration: t = 0.35 ms.

[0032] The electronic detonator of Example 1 was subjected to conductivity and vibration tests, and the test results were all qualified.

[0033] Example 2 The following process parameters are used for soldering nickel electronic detonator leads with a diameter of 0.15mm and a length of 1mm to copper chip pads with a thickness of 0.08mm and a pad diameter of 0.25mm: Welding material: Tin-silver-copper alloy (Sn96.5Ag3Cu0.5); Characteristics of welding materials: density ρ_SnAgCu=7300kg / m³, specific heat capacity c_SnAgCu=240J / (kg·K), melting point T_m_SnAgCu=217°C, thermal conductivity 60W / (m·K); Initial temperature: T_0 = 25°C; Solder pin length: 0.25mm (based on pad diameter); Cross-sectional area of ​​the weld joint: A = π * (0.25 mm / 2)² = 0.0491 mm² = 4.91 * 10⁻⁸ m²; Laser energy loss coefficient: η = 0.3; Laser mode: Pulsed laser mode; Laser power: P=10W; Pulse frequency: f = 100 Hz; Pulse width: τ = 1ms; Welding energy E = 1.25 * 10^-6 J; Laser action duration: t = 1.25 ms.

[0034] The electronic detonator of Example 2 was subjected to conductivity and vibration tests, and the test results were all qualified.

[0035] As can be seen from the test results of Examples 1 and 2 above, the welding method of this application has good reliability. Furthermore, the beneficial effects of this application are significant.

[0036] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for soldering electronic detonator leads to a chip, characterized in that, include: The characteristics of the welding material are determined based on the type, thickness, and size of the electronic detonator leads and chips. Based on the characteristics of the welding material, laser welding parameters are determined; the laser welding parameters include at least one of laser power, pulse frequency, pulse width, and welding speed. The laser treatment duration is determined based on the characteristics of the welding material and the laser welding parameters. Based on the laser action duration, the laser generator is controlled to weld the electronic detonator leads and the chip's solder joints.

2. The welding method as described in claim 1, characterized in that, The step of determining the laser application time based on the characteristics of the welding material and the laser welding parameters includes: Based on the properties of the welding material, determine the welding energy required per unit length of weld joint; The duration of laser action is determined based on the welding energy and the laser welding parameters.

3. The welding method as described in claim 2, characterized in that, The welding energy is determined according to the following formula: in, It is the laser energy loss coefficient, and L is the length or diameter of the solder joint. It is the density of the welding material, It is the specific heat capacity of welding materials, It is the melting point of the welding material. The initial temperature of the solder joint, It is the cross-sectional area of ​​the weld joint.

4. The welding method as described in claim 3, characterized in that, The laser generator operates in continuous laser mode; the laser duration is determined according to the following formula: in, The welding energy, The laser power, This refers to the welding speed.

5. The welding method as described in claim 3, characterized in that, The laser generator operates in pulsed laser mode; the laser duration is determined according to the following formula: in, The welding energy, The laser power, The pulse frequency, It is the pulse width.

6. The welding method as described in claim 1, characterized in that, The step of controlling the laser generator to solder the electronic detonator leads and chip solder joints based on the laser action duration includes: The welding area of ​​each of the aforementioned solder joints is monitored in real time, and the laser treatment duration is adjusted based on the monitoring data; the monitoring data includes the temperature of the solder joint and the range of the heat-affected zone. Based on the adjusted laser action duration, the laser generator is controlled to weld the electronic detonator leads and the chip's solder joints.

7. The welding method according to any one of claims 1-6, characterized in that, The welding process is carried out under inert gas protection.

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