(d) Figure Q2 shows the strength of a steel alloy with high hardenability over the welding region. i) ii) Briefly explain why the strength of the fusion zone is higher than the heat-affected zone (HAZ) and the main reasons for showing such behavior. [4 marks] The above attribute affects adversely on the part quality due to non-uniform strength of the material. Suggest a method to minimize this effect, and name a process to reverse the effect by obtaining a homogeneous microstructure. [4 marks] Fusion zone Heat- affected- zone Fast cool Fusion zone Cold-work unaffected base metal Slow cool Recrystallization zone Grain growth zone Figure Q2 Distance