Localized melting defect
Localized melting is the unintentional melting of steel outside the joint faces caused by an uncontrolled arc. This leads to microstructural changes and can reduce corrosion resistance.
Physical-Chemical Mechanism of Action
Localized melting occurs when the arc is too strong or irregular during welding. This causes certain areas of the steel to be heated above its normal melting point and melt.
Metallurgical Relevance & Risks in Welding
Localized melting can lead to various problems. It can alter the structure of the steel by locally changing the microstructure. This can lead to increased susceptibility to cracking and corrosion. Additionally, it can cause uneven stresses in the material, which in turn can lead to damage.
Workshop Practice & Instructions
To avoid localized melting, it is important to control the arc. This can be achieved by adjusting welding parameters such as voltage and current. Careful preparation of the steel and proper joint tacking also help reduce the risk of localized melting.