As a brand-new material, stainless steel has been commonly used in aerospace, car parts, and other fields since its deterioration resistance and formability.
The application of laser welding to stainless steel inhabits a very crucial position, specifically in the vehicle market. The body is all connected by welding.
Due to the impact of many factors, stainless steel plate welding has a contortion problem. It is difficult to manage, which is not favorable to the sustainable development of related fields.
It is of excellent significance to reinforce the research study on laser welding contortion of stainless steel plates.
Overview of Laser Welding
Laser welding utilizes laser energy as a heat source to melt and connect the workpiece.
In the laser welding procedure, when the laser irradiates the surface area of the material to be bonded, part of it will be shown, and the rest will be soaked up to go into the material to finish the welding target.
In short, the process of laser welding is to utilize the high-power laser beam focused by the optical system to irradiate the surface of the product to be bonded, then make full use of the light energy absorption of the material to heat and other treatment, and lastly, form a welding joint after cooling.
In general, laser welding is primarily divided into thermal conduction welding and deep penetration welding.
Damage of Welding Deformation and Primary Factors Affecting Welding Contortion
The primary elements affecting welding contortion are welding existing, pulse width, and frequency.
With the increase of welding current, the weld width boosts, and the spatter appears slowly, which results in oxidation contortion and roughness on the weld surface area.
When the pulse width reaches a certain extent, the heat conduction energy usage of the product surface area also increases.
Evaporation makes the liquid splash out from the molten swimming pool, which causes the decline of the cross-sectional area of the solder joint and affects the strength of the joint.
The influence of welding frequency on welding deformation of stainless steel plate is closely related to the density of steel plate.
For instance, for a 0.5 mm stainless steel plate, when the frequency reaches 2 Hz, the weld overlap rate is higher;
When the frequency reaches 5 Hz, the welding joint burns seriously, the heat-affected zone is large, and the contortion occurs.
For that reason, it is important to enhance the efficient control of welding contortion.
Reliable Steps to Avoid Laser Welding Contortion
To reduce the deformation of laser welding and improve the welding quality of stainless steel plate, it can begin by enhancing the welding process specifications, and the specific operation techniques are as follows:
Actively present the orthogonal experiment technique
The orthogonal experiment approach primarily describes the mathematical stats method through orthogonal table analysis and arrangement of multi-factor experiments.
It can utilize fewer experiments to get effective outcomes and infer the finest application scheme.
Simultaneously, it can also perform in-depth analysis, get more pertinent details, and offer the basis for specific work.
Typically, welding current, pulse width, and laser frequency are chosen as the crucial objects, and the welding contortion is considered the index and controlled at the minimum.
It needs to abide by rationality and manage the level of aspects in a suitable variety.
For instance, for the stainless steel plate with a height of 0.5 mm, the current can be controlled between 80 ~ 96 I/A and the frequency between 2 ~ 5 f/Hz.
Selection of orthogonal table
In general, the level of experimental factors should be consistent with the level number in the orthogonal table. The variety of elements needs to be less than the variety of columns in the orthogonal table.
An affordable style of orthogonal table can offer corresponding support and help for the follow-up research.
Range analysis of test results
According to the test outcomes of stainless steel plate with a thickness of 0.5 mm, the range difference of each column is not equal, which proves that different levels of each aspect have particularity, and the impact is not the very same.
The order of influence on laser welding contortion is present, pulse width, and frequency.
Considering all the aspects, the laser’s very best welding process specifications must be managed: existing 85 A, pulse width 7 ms, frequency 3 Hz.
The welding process criteria should be controlled in three worths to guarantee the minimum welding contortion of stainless steel plates with a density of 0.5 mm.
For the stainless steel plate with a density of 0.8 mm, the existing pulse width and frequency ought to be managed at 124 A, 8 ms, and 4 Hz, respectively, to ensure the minimum deformation based upon satisfying the tensile strength of the weld.
The thickness of the stainless steel plate is 160 A, 11 ms, 5 Hz.
In the laser welding procedure, the welding workers control the parameters in a sensible range, which can enhance the welding quality and performance prevent the contortion of the steel plate, and satisfy the production demand.
With the fast advancement of science and technology, the control of welding deformation technology is also established, such as applying limited aspect simulation in welding deformation control.
Using welding temperature and stress to avoid welding deformation, the tension balance of stainless-steel plates can be improved.
While preventing steel plate welding deformation, the welding quality can be improved to promote the healthy advancement of related fields.
According to the above, laser welding innovation plays a favorable role in improving the quality of the welding process as an efficient welding technology.
Nevertheless, stainless-steel plate laser welding has deformation and other issues due to laser current and other elements.
So the welding personnel can take the orthogonal experiment approach to acquire the very best process parameters of various thickness steel plates, combined with the welding parameters to continuously enhance the welding quality to prevent the event of steel plate deformation.