A simplified analytical method to determine the range of the heat affected zone and its components during welding is presented. Heat affected zone (HAZ) is an area formed during welding in which, as the result of temperature, some structural changes in the welded material occured. Knowledge of the area and sub-areas of HA Z is important from practical point of view, since the area of the fine-grained HAZ is a critical place in terms of creep strength and thermal fatigue. Heat affected zone is often the cause of future damage of many devices in which welding technology was used for their repair.
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