Improving the quality of high power laser welding laser
Whether ship or the reactor vessel, the welding in the process of the formation of various reliable metal structure is very key to a way of operating.
When welding failed, the whole structure is often fail, so expect of welding quality only will be more and more high.
Using local heating source technology such as welding, is likely to lead to the generation of deformation.
Thick metal parts of the welding process is not stable, if there is no external power will be difficult to control.
In high power laser welding, laser intensity of the highest area of a small amount of metal will evaporate.
Deep penetration in the workpiece will create a vertical cavity is known as the 'holes'.
During the process, the laser beam is not only melting metal, also can produce metal vapor.
The dissipation of the steam pressure of molten metal and part to replace it.
At the same time, continue to melt.
The result is a deep and narrow and full of steam hole, or called 'holes' (
It is surrounded by molten metal.
As the movement of the laser beam, holes can then move on the workpiece.
Molten metal solidification flow around the holes and along the way.
This creates a deep and narrow welds with uniform internal structure.
As is known to all, with deep fusion welding to welding aluminum problem is mainly caused by the low viscosity of the melt high dynamic behavior.
Coupled with high thermal conductivity, the resulting molten pool is very wide.
Welding surface becomes unstable, the result is the metal droplet splash and spray, and thus produce not weld, bite edge, arc pit, full welding defects such as holes or empty, all these defects will be an adverse effect on the mechanical properties of the welding.
If there are missing materials, often need electricity arc welding for reprocessing, to fill the lack of materials or make weld visual effect is better, this is an indicator of surface quality.
In addition, in some areas, smooth weld surface becomes very important, such as the food industry, mainly because of rough surface may carry bacteria.
Control of welding process will bring a side effects, namely the acceleration of the weld metal drop.
These droplets makes the whole process as 'dirty', and leads to the lack of weld material after cooling.
Second, Ma Lange,
Effect lead to non-uniform welding seam, it is also the workpiece in a source of stress and/or deformation occurred.
Part of the weld pool surface tension and the electromagnetic force under the action of moving, leading to non-uniform distribution of material and welding solidification speed is different from different parts of the molten pool.
Once the weld solidification, due to the uneven distribution and the cooling time, it may be made of different materials.
Laser welding metal laser welding