That portion of the base metal that has not been melted but whose microstructure or mechanical properties have been altered by the heat of welding, brazing, soldering, forming, or cutting.
the immediate region around a thermal machining process (laser ablation, electrical discharge machining, etc) where the mechanical properties of the work material are changed by rapid cooling (quenching), usually makes work material locally more brittle
Heat affected zone is the region close to the laser irradiated area that obvious temperature change from original area happens, or obvious strain state change happens.
This is the thermally affected area of metal immediately adjacent to the weld in a part. Normally welding conditions must be controlled, or some form of preheat of post-heat treatment applied after welding, to assure that this area does not cause premature failure of the part in service.
The part of the parent metal which is metallurgically affected by the heat of welding or thermal cutting but not melted. (Also known as the zone of thermal disturbance).
That portion of the base metal which has not been melted, but whose mechanical properties or microstructure has been altered by the heat of welding or cutting.
Part of parent metal which is metallurgically affected by welding but not melted. (Weld zone, fusion zone.)
During laser cutting of steels a huge amount of energy is conducted into the work piece resulting in changes in the material properties and the microstructure of the steel. This activity results in a narrow zone exactly adjacent to the laser cut that experiences changes in material properties. Typically, the changes occur either as grain refinement, or as precipitation of carbides (which are harmful for corrosion resistance properties of steel) and other impurities such as sulfides and phosphides. The entire region which differs from the base material in properties can be defined as the heat affected zone or HAZ.