How does T10 steel differ from manganese steel in these pieces?
Updated Feb 2026
T10 is a tungsten-alloyed tool steel prized for its fine grain structure and ability to hold a keen edge through extended handling and display. The tungsten content increases hardness and heat resistance, and T10 responds exceptionally well to clay tempering, producing a pronounced, natural hamon line along the blade. Manganese steel, by contrast, contains a higher proportion of manganese, which enhances toughness and flexibility. It is slightly more forgiving if the blade experiences lateral stress, making it a resilient choice for a full-tang collectible meant to be drawn and resheathed regularly. Both steels are hand-forged and differentially hardened in these aikuchi pieces, so the practical difference for display collectors comes down to personal preference between a harder edge profile and a more flexible spine.