Armor Plate - Cast. Metallurgical Examination of Failed Bow Machine Gun Casting from Cadillac Light Tank, M5.

The object of this work was to determine the metallurgical properties of the bow machine gun casting which failed during the abllistic test of the Cadillac M5 hull in the Canadian Cold Test Program. The unsatisfactory shock resistance of the bow machine gun casting at subzero temperatures is correlated with the poor metallurgical properties namely, low alloy content, and resulting inadequate hardenability, and low impact properties. the fracture of the casting was finely crystalline, which is associated with heterogeneous microstructure and poor shock resistance, especially at low temperatures.