Laser Welding｜Quality Control & Solutions |

• Quality Control in Laser Welding?

With high efficiency, high precision, great welding effect, easy automatic integration, and other advantages, laser welding is widely used in various industries and plays a pivotal role in metal welding industrial production and manufacturing, including in the military, medical, aerospace, 3C auto parts, mechanical sheet metal, new energy, sanitary hardware, and other industries.

However, any welding method if not mastered its principle and technology, will produce certain defects or defective products, laser welding is no exception.

Mimowork Laser Welder

• What should I do to solve those Defects?

Only a good understanding of these defects, and learning how to avoid these defects, to better play the value of laser welding, processing a beautiful appearance, and good quality products.

Engineers through long-term experience accumulation, summed up some common welding defects of the solution, for industry colleagues' reference!

What are the Five Common Welding Defects?

>> Cracks

>> Pores in Weld

>> The Splash

>> UnderCut

>> The Collapse of the Molten Pool

If you would like to know more about HandHeld Laser Welders, you can check out our page for more information through the link down below!

Application Overview - Handheld Laser Welding

◼ The Cracks when Laser Welding

The cracks produced in laser continuous welding are mainly hot cracks, such as crystallization cracks, liquefied cracks, etc.

The main reason is that the weld produces a large shrinkage force before the complete solidification.

Using the wire feeder to fill wires or preheating the metal piece can reduce or eliminate the cracks shown during laser welding.

The Cracks in Laser Welding

◼ Pores in Weld

Pores in Weld

Usually, the laser welding pool is deep and narrow, and metals normally conduct the heat very well and super-fast. The gas produced in the liquid molten pool does not have enough time to escape before the welding metal cools down. Such a case is easy to lead to the formation of pores.

But also because the laser welding heat area is small, the metal can cool down really fast, and the resulting porosity shown in laser welding is generally smaller than the traditional fusion welding.

Cleaning the workpiece surface before welding can reduce the tendency of pores, and the direction of blowing will also affect the formation of pores.

◼ The Splash

◼ The Collapse of the Molten Pool

The splash produced by laser welding seriously affects the weld surface quality and can contaminate and damage the lens.

The spatter is directly related to the power density and can be reduced by properly reducing the welding energy.

If the penetration is insufficient, the welding speed can be reduced.

The Splash in Laser Welding

If the welding speed is slow, the molten pool is large and wide, the molten metal amount increases, and the surface tension is difficult to maintain the heavy liquid metal, the weld centre will sink, forming collapse and pits.

At this time, it is necessary to reduce the energy density appropriately to avoid the collapse of the molten pool.

The Collapse of the Molten Pool

◼ Undercut in Laser Welding

If you weld the metal workpiece too fast, the liquid metal behind the hole pointing to the centre of the weld has no time to redistribute.

Solidifying on both sides of the weld will form a bite. When the gap between two pieces of work is too large, there will be insufficient molten metal available for caulking, in which case welding edge biting will also occur.

At the ending stage of laser welding, if the energy drops too quickly, the hole is easy to collapse and resulting in similar welding defects. Better balance power and moving speed for laser welding settings can solve the generation of edge biting.