Ultrasonic Welding vs Laser Welding?
Ultrasonic welding and laser welding are both efficient welding methods, what’s the difference between them? Here we analyze the principle, advantages, and application of the two welding ways.
Ultrasonic welding
Ultrasonic welding is an efficient welding method by using ultrasonic systems (ultrasonic generator, transducer, booster, welding horn) to emit high-frequency vibration waves and transmit them to the surface of the two workpieces, under pressure, the surface of the two workpieces rub against each other to form a fusion between molecular layers.
Ultrasonic metal welding machines can be used for welding non-ferrous metals such as gold, silver, copper, aluminum, and nickel. Ultrasonic metal welding has special requirements for metal materials: the metal must have a certain ductility and a certain degree of purity.
Advantages of ultrasonic metal welding
* Low pressure on the weld metal workpiece and low energy consumption;
* The welded metal material does not melt and the ultrasonic welding does not fragile the metal properties;
* Good electrical conductivity of the welded metal, with a low coefficient of resistance, close to 0;
* Also low requirements for the surface of the metal, oxidized or plated metals can be welded;
* Very fast welding speed, good stability, and highly fatigue-resistant welded joints;
* Easy integration into automated production processes.
Friendly tips: Ultrasonic metal welding is not suitable when the thickness of the metal workpiece is deep and the hardness is high.
Advantages of ultrasonic plastic welding
* No preheating, cleaning, and other pre and post-processing required;
* No need to add any flux, no sparks for welding;
* Fast welding speed, high welding accuracy, and strength;
* Good sealing (air tightness and water tightness);
* Good stability and minimal deformation of the welded workpiece;
* Clean, beautiful, flat, and smooth surface after welding;
* Safe and eco-friendly without any welding slag, sewage, harmful gases, etc.
Friendly tips: Ultrasonic plastic welding is not suitable for welding plastic workpieces with shaped and complex structures, and there are restrictions on the size of the welding area for plastic parts (Large plastic parts require customized multi-head ultrasonic welding machines for welding).
Laser Welding
Laser welding is an efficient and precise welding method using a high energy density laser beam as a heat source. By focusing the laser beam on a very small area through an optical system, a highly concentrated heat source zone is created at the welded area in a very short time, thus melting the workpieces and creating a solid weld joint and seam. As it does not require vibration or relative movement between workpieces, it is possible to join delicate parts and fragile components without risk of damage, while allowing precise alignment and sealing between workpieces.
Advantages of laser metal welding
* Laser welding with low thermal stress, low material deformation, and no subsequent treatment.
* The possibility of welding high melting point, high strength alloy materials.
* Can weld difficult materials such as titanium and quartz and weld materials with different properties;
* Non-contact processing, no tool loss, and no tool changeover problems.
* Laser welding of product workpieces in vacuum environments and complex internal structures.
Disadvantages of laser metal welding
* The metal workpiece needs to be cleaned before laser welding, otherwise, more metal particles will appear on the surface of the workpiece after welding.
* Laser welding of metal sometimes results in surface collapse, cracking, and edge biting.
* The surface of the metal is prone to porosity under the action of the high-power laser, reducing the overall performance of the weld.
* The laser welding metal process requires that the position of the beam on the workpiece must not be shifted, requiring the addition of metal welding wire.
Advantages of laser plastic welding
* Non-contact processing, precision, solid and hermetic (gas-tight, water-tight) welding, hygiene, and safety.
* Reduction of vibration stresses and thermal stresses in welded products.
* No damage to the surface and surrounding material, and no deformation of the welded part.
* Suitable for bonding 3D, complex shapes, and tiny metal products.
Disadvantages of laser plastic welding
* Laser welding machines are unable to weld plastics with a high degree of crystallization.
* laser welding cannot perform the bonding task when a certain percentage of glass fiber or flame retardant has been added to the plastic.
* The thickness of the plastic material reaches a certain level where the laser cannot penetrate, which also results in failure to weld.
* When the material added to the plastic is impervious to light, laser welding will also not be able to complete the bonding task.
The difference between ultrasonic welding and laser welding:
| Properties | Ultrasonic Welding | Laser Welding |
| Working Principle | Uses high-frequency vibration waves | Uses a high energy density laser beam |
| Material Removal Rate | Low | High |
| Penetration power | Low, can weld thin plates well. | High, can penetrate deep into the metals. |
| Electrode | No | No |
| Weld Strength | Lower than laser welding | High |
| Welding Speed | Generally, laser welding speed is lower than ultrasonic welding. | |
| Plastic welding | Compared with ultrasonic welding, laser welding is capable of welding complex geometrical and micro-sized workpieces. | |
| Metal welding | Suitable for thick materials. | Suitable for relatively thin materials. |
| Machine Price | Generally, laser welding machine price is higher than ultrasonic welding machine. | |
Both processes have their advantages and disadvantages, you can carefully assess your project requirements and then determine which process is most suitable for you, or you can consult our technical team to provide you with the most professional suggestions.
Application
- Laser Welding
- Ultrasonic Welding
Laser welding technology has been widely applied in the medical, automotive, electronics, and packaging sectors.
Medical industry: liquid tanks, liquid filter materials, hose connectors, hearing aids, etc.
Automotive industry: gearshift frames, engine sensors, cab frames, hydraulic oil tanks, filter frames, lights, etc.
Electronics industry: in the packaging of integrated circuits and semiconductor device housings, molybdenum focusing electrodes with stainless steel support rings, fast hot cathode filament assembly welding, sensors or temperature control in the elastic thin-walled corrugated sheet welding, etc.
Ultrasonic welding technology has been widely applied in medical, automotive, electronics and packaging, toys, home appliances, etc. industries.
Automotive industry: bumpers, front and rear doors, lamps, brake lights, reflectors, etc.
Home appliance industry: lampshades, washing machine dehydration tanks, TV housings, steam ironing doors, etc.
Packaging Industry: Closure of hoses, the connection of special strapping;
Toy industry: No screws, adhesives, glues, or other auxiliaries are required, resulting in a significant reduction in costs.
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