""technically the wcz and the tmaz are both "thermo-mechanically affected zonez" but due to the vastly different microstructures they possess they are often considered separately. the wcz experiences significant dynamic recrystallisation (drx), the tmaz does not. the material in haz is not deformed mechanically but is affected by the heat. the region from one tmaz/haz boundary to the other is often referred to as the "tmaz thickness" or the plastically affected zone (paz). for the remainder of this article this region will be referred to as the paz""