Partial Melting
Partial melting is the incomplete fusion of multiphase alloys when reaching the solidus temperature, leading to susceptibilities like hot cracking in the heat-affected zone. It results from local concentration differences.
Physical and chemical mechanism
Partial melting occurs when, in multi-phase alloys, only parts of the alloy melt while others remain solid. This can be caused by local differences in concentration or uneven heat distribution.
Metallurgical relevance and welding risks
Partial melting leads to susceptibilities such as hot cracking in the heat-affected zone. Incomplete melting can cause uneven stresses and distortion in the material, which may lead to cracks or destruction of the weld seam.
Workshop practice and instructions
To avoid partial melting, it is important to ensure even heat distribution and a constant welding process. This can be achieved by using suitable shielding gases, correct welding parameters, and careful preparation of the workpieces.