Question

Generally, the different zones formed in friction stir weld joint of work hardenable steel in an annealed condition in increasing order of their average hardness are

 1. Base metal, weld zone, HAZ

 2. Weld zone, HAZ, base metal

 3. Base metal, HAZ, weld zone

 4. HAZ, weld zone, base metal

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Answer 1

HAZ,weld zone,base metal