Updated 06/13/2023

Finding a solution to the bubbles that are created during welding in Aluminum. sahar gordo levin shaked cohen farjon

5 Whys #
Causes Chain
Root Cause Analysis

After welding, porosity is created in the welding area - lots of bubbles which weaken the material and cause weak welding, cracks and corrosion.


1. Use a higher quality welding rod and a higher welding current. 2. Ensure the welding area is clean and free of dirt, rust, oil, and grease. 3. Use a higher welding speed. 4. Use a gas shield when welding. 5. Use a backing strip or filler material when welding. 6. Use a post-weld cleaning process to remove any remaining porosity. 7. Ensure the welding area is properly ventilated.


Shrinkage during the process of solidification of the metal and trapping of air and undissolved hydrogen


Shrinkage during solidification can be minimized by controlling the rate of cooling and solidification. This can be done by controlling the rate of heat transfer from the molten metal to the mold, as well as controlling the size and shape of the mold. Additionally, reducing the amount of air and undissolved hydrogen in the molten metal can help to reduce shrinkage. This can be done by using degassing techniques such as vacuum or inert gas purging, or by using fluxes or


The welding process may produce gases such as hydrogen, carbon dioxide and steam, when welding is performed and the metal melts and solidifies these gases may be trapped.


The best way to eliminate these gases is to use a fume extractor. A fume extractor is a device that is used to capture and remove welding fumes and other airborne contaminants from the air. It works by drawing air through a filter which captures the welding fumes and other airborne contaminants, and then exhausts the clean air back into the environment.


In a liquid there is a higher solubility of a gas than in a solid.

This is the fundamental reason for the problem (FRP).

Lowering the temperature - lowering the temperature will reduce the solubility of the gas in the liquid, and allow it to be released from the liquid, but since welding has to be done at high temperatures, this action may not help. Increasing the pressure may also help to lower the solubility. Performing laser welding - will help to control the speed of the welding and thus it is possible to perform rapid heating and cooling of the area so that the gas vapors will not be enough to form

Jun 12 2023 10:52:36 am
Action Preventing Action #
Customer actions
Answer the question: What keeps him busy?
Companies that manufacture a metal product may use the joining of two metals by welding them.

Action purpose: Why is the customer doing it? What is he trying to achieve doing it?

Welding of components and connection of metals in order to create different and diverse connections for the various industries, sometimes two or more different types of metals are needed due to different weight or need for the product and it is necessary to connect them. These companies use the welding process to perform this operation.

Action Preventing Action: What should be done to prevent the customer from doing the action?

If the welding is not satisfactory and there are many failures, the customer will not be able to use the welding equipment because it will not give him a satisfactory answer

Customer needs: How can we achieve it?

Performing good and efficient welding without welding failures or bubbles that will weaken the connection will make the customer provide a better and more efficient product and therefore the customer will want this action.

Jun 12 2023 11:32:27 am
Effective Brainstorming #

control the speed of the process, thermal gradient, dynamics of melt pool flow and solidification Can help the welding failures. Performing laser welding can help control these details and improve the welding results.

controlled hydrogen content, air flow velocity, and room temperature
Jun 12 2023 11:42:12 am
ImplementationNot EasyValidationEasy
control the speed of the process, thermal gradient, dynamics of melt pool flow and solidification to ensure gas escape.
Jun 12 2023 11:42:29 am
High arc currents cause the interaction effect of laser arc and melt flow so that bubbles come out of the molten pool and reduce porosity
Jun 12 2023 11:43:16 am
A suitable torch position, optimal welding conditions, and a suitable welding range can also control porosity
Jun 12 2023 11:42:58 am
ImplementationNot EasyValidationNot Easy
Configure the gas flow meter to the correct flow settings. Depending on the welding technique, the gas flow should be between 22 to 30 cubic feet per
Jun 12 2023 11:42:43 am
Jun 12 2023 11:35:59 am
Round - Robin Ranking #
to control the speed of the process, thermal gradient, dynamics of melt pool flow and solidification using a laser beam welding
to use the right welding method and materials
Keep the welding area clean and perform the welding under nitrogen injection in order to prevent oxidation of the area
to use the right parameters and techniques
Jun 12 2023 4:55:07 pm
Inventive principles #
We will perform laser welding
It will be possible to control the speed of the process, thermal gradient, dynamics of melt pool flow and solidification, as a result the Welding performance will be better and with fewer failures
It will be requires local suction control and protections against laser radiation.
Improving parameter
Description of what is improving:
As soon as the welding speed can be controlled and fast welding can be performed, it is possible to prevent the shooting of gas bubbles inside the material.
Selected improving parameter:
Worsening parameter
Description of what is worsening:
Laser technology has been developing a lot in recent years, but there are still difficulties in using this method. The welding machines are large and a fiber optic cabinet and cooling chiller are needed. In addition, due to the laser radiation and the wavelength, which may damage vision or cause a burn (depending on the process and the desired welding), appropriate protective measures are necessary, such as suitable laser glasses according to the wavelength of the laser, and additional protection such as beam blockers and a suitable position for laser use.
Selected worsening parameter:
Device complexity
Matching principles:
  • 4
  • 10
    Preliminary action
  • 28
    Mechanics substitution
  • 34
    Discarding and recovering
  • Jun 12 2023 5:34:56 pm
    Login to comment
    Anatoly Agulyansky avatar

    Anatoly Agulyansky


    Great project. I like your 5+Whys analysis especially. Thank you.

    Similar projects

    אספקטים בשיפור עמידות של פותחני בקבוקים

    thombr avatar