In Han culture circle there seems no such weapon with complex pattern on steel,especially in early time.Moreover,how to add that pattern?Carve?Corrade?

• 汉文化圈里好象不会出现这种在钢铁上有复杂花纹的兵器，特别是早期。而且，那个花纹是如何弄上去的，錾刻?腐蚀?