The generation mechanism and suppression measures of spatter in water cooling plates welding
Release Time : 2025-05-06
In the process of water cooling plates welding, the appearance of spatter will not only affect the appearance quality of the welded joint, but also reduce the welding strength, increase the risk of defects such as pores and cracks, and even interfere with the normal operation of the welding equipment in severe cases, affecting production efficiency and cost control. In-depth exploration of the generation mechanism of spatter and targeted formulation of suppression measures are crucial to ensure the quality of water cooling plates welding.
In the arc welding process, the physical properties of the arc are an important cause of spatter. Under the high-speed movement and high temperature of the arc plasma, the molten droplet will be subjected to strong electromagnetic force, plasma flow force, etc. When the welding current is too large, the electromagnetic contraction force will cause the molten droplet to neck. If the molten droplet transition is unstable at this time, the metal liquid column at the necking point may break, forming fine metal particles that splash out. In addition, unstable arc combustion, such as arc length fluctuations and arc blow, will also destroy the normal transition of the molten droplet and cause the molten droplet to splash. For example, in gas shielded welding, insufficient shielding gas flow or insufficient gas purity will make the gas shielding layer around the arc unstable, and the outside air will invade, causing arc disorder, which will then cause spatter.
Metallurgical reactions during water cooling plates welding also cause the generation of spatter. Metal materials commonly used in water cooling plates, such as aluminum alloys and copper alloys, react with oxygen and nitrogen in the air at high welding temperatures to generate metal oxides and nitrides. The generation of these compounds will change the surface tension and viscosity of the molten pool metal. When the gas in the molten pool is precipitated, a large pressure will be generated, causing the molten pool metal to spray outward to form spatter. For example, when welding aluminum alloys, the aluminum oxide particles generated by the reaction of aluminum and oxygen will reduce the surface tension of the molten pool, making the molten pool metal more likely to spatter. In addition, the carbon in the molten pool reacts with oxygen to generate carbon monoxide gas. If the gas does not have time to escape, it will expand during the solidification of the molten pool, which will also cause the molten pool metal to spatter.
The selection of process parameters in water cooling plates welding directly affects the generation of spatter. Improper matching of welding current and voltage is a common factor. When the voltage is too high, the arc length increases, and the air resistance of the molten droplet during the transition process increases, which easily leads to the dispersion of the molten droplet and the formation of spatter; if the current is too large, the molten pool temperature will be too high, the metal evaporation will intensify, and spatter will be caused. If the welding speed is too fast, the molten pool metal will not have enough time to fully transition, resulting in the molten droplet not being able to smoothly enter the molten pool after leaving the end of the welding wire, thus generating spatter. In addition, the mismatch between the wire feeding speed and the welding speed will also cause unstable molten droplet transition and cause spatter.
Measures can be taken to optimize the characteristics of the welding power supply for spatter caused by the arc physical process. A welding power supply with waveform control function is used to adjust the current waveform to reduce the current peak value during the molten droplet transition stage, reduce the excessive effect of the electromagnetic contraction force on the molten droplet, and make the molten droplet transition smoothly. At the same time, the composition and flow rate of the shielding gas are reasonably controlled. For example, in carbon dioxide gas shielded welding, the appropriate addition of argon can improve the stability of the arc and reduce spatter. In addition, pulse welding technology is used to periodically change the welding current to make the molten droplet transition in the form of pulses, improve the controllability of the molten droplet transition, and effectively suppress the generation of spatter.
In order to reduce spatter caused by metallurgical reactions, it is necessary to strengthen the control of welding materials. Selecting welding materials containing deoxidizers, arc stabilizers and other ingredients, such as using welding wires containing deoxidizing elements such as magnesium and titanium when welding aluminum alloys, can reduce the oxygen content in the molten pool, reduce the generation of oxides, and thus reduce spatter. At the same time, strictly control the welding environment and adopt gas protection measures to prevent air from invading the molten pool and reduce the occurrence of metallurgical reactions. Strictly cleaning the surface of the water-cooled plate before welding to remove impurities such as oil stains and oxide films can also effectively reduce the spatter generated by metallurgical reactions.
Reasonable adjustment of welding process parameters is the key to suppressing spatter. Through experiments and data analysis, the optimal matching values of welding current, voltage, welding speed and wire feeding speed are determined. For example, under the premise of ensuring welding quality, appropriately reducing welding current and voltage can reduce the heat input of the molten pool, reduce metal evaporation and spatter. Adjust the welding speed to match it with the wire feeding speed to ensure that the molten droplet can smoothly transition into the molten pool. In addition, the use of multi-layer and multi-pass welding process can disperse welding heat, reduce the temperature of the molten pool, and reduce the generation of spatter.
With the development of welding technology, new welding technology and auxiliary equipment have provided new ways to suppress spatter. For example, the use of laser-arc hybrid welding technology, which utilizes the high energy density of the laser and the good adaptability of the arc, can improve the stability of the molten pool and reduce spatter. In terms of welding equipment, installing a spatter collection device can timely collect spatter generated during welding to prevent it from affecting the welding environment and equipment. At the same time, developing welding equipment with intelligent control functions, through real-time monitoring of various parameters in the welding process and automatic adjustment of process parameters, to achieve precise control of spatter.