At melee combat range, you will engage with your attacker at a modestly safe distance, and most likely employ a weapon that falls into one of two categories:
Bludgeons: weapons in this category include any object that can be used to cause a depressive fracture on the skull and penetrate the brain cavity. They include, but are not limited to formal weapons such as maces, war hammers, and cudgels, in addition to any number of improvised blunt trauma tools.
Blades: any weapon two to three feet in length with a single or double sharpened edge falls into this armament class, and includes swords, machetes, hand axes, and tomahawks.
Bladed weapons of sufficient weight can be used to strike and penetrate the skull. Lighter edged weapons made of thinner steel that may have difficulty penetrating the cranium should focus attacks on the soft tissue of the neck.