Welding involves various metallurgical phenomena, including melting, freezing, diffusion, precipitation, thermal strains, and shrinkage. If disregarded or misunderstood, these effects can lead to cracking, porosity, or welds with poor properties. This course builds on the fundamental principles described in Metallurgy I to provide a basic understanding of the nature of metals, the metallurgical phenomena involved in welding, and the effects of these phenomena on the properties of welded materials. Click on the Course Modules tab below to see a list of the topics covered.