PURPOSE: To form surely a hardened layer which has high wear resistance and durability and good workability by using a thermal spraying material consisting of a ferrous metallic material of which the contents of carbon, silicon and phosphorus are regulated by the specific formulas.

CONSTITUTION: The contents (x), (y), (z) of carbon, silicon and phosphorus of a thermal spraying material consisting of a ferrous metallic material are regulated to 0≤y≤-2.0x+8.6, -0.32x+1.39≤z≤4.0, 3.0≤x≤4.3. The ferrous metallic material having the component compsn. consisting of, for example, 3.10W3.50% C, 0.60W0.80% Si, 0.35W0.45% P, 0.20W0.40% Mn and ≤0.10% S is melted and is quickly cooled and pulverized by an atomizing method, etc. Such powder is classified and screened to prescribed grain sizes to form the thermal spraying material. Said material is thermally sprayed by a plasma spraying device, etc. onto the surface of a member to be hardened such as metal or the like.