What is porosity in welding?

Porosity in welding refers to the presence of small voids or holes in the welded material, caused by the entrapment of gases such as nitrogen, hydrogen, or oxygen during the welding process.

Porosity can weaken the weld and compromise its integrity, leading to potential failure under stress or pressure. It can also reduce the overall quality and appearance of the welded joint.

Common causes of porosity in welding include inadequate shielding gas coverage, improper welding technique, contaminated base metal or filler material, and high welding speeds that do not allow gases to escape.

To prevent porosity in welding, it is essential to ensure proper shielding gas coverage, use clean base metals and filler materials, follow recommended welding procedures, and avoid excessive welding speeds. Additionally, preheating the base metal and using proper welding techniques such as back purging can help minimize the risk of porosity.