Welding of high-carbon armor steel is a complex procedure, and there is a possibility of welding flaws in the weld zone as cracks and pores. When welding armor steel, austenitic filler material is commonly utilized to reduce the dangerous effects of hydrogen content spread into the fusion line. The heavy structural engineering is similar to an armored military vehicle, which is routinely subjected to impact and dynamic stresses. In this condition, the fusion zone is critical to understand the dynamic features of the welded joints. On Charpy V specimens, impact testing was conducted and the impact energy was achieved at 110 J in the weld joint. The multi-pass welding attained different hardness values in the weld zone. These different hardness values were changed by microstructures with weld thermal cycles. The austenite with a delta ferrite matrix in the fusion zone has a lower hardness value as compared to the martensite with retained austenite in the base metal. Microstructural features are very important to analyze the crack growth on the fracture surface. Optical microscopy, energy dispersive X-ray analysis (EDAX), and scanning electron microscopy (SEM) were utilized to analyze the microstructure characteristics of the armor weldments.