| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a powder-molded entirely-nitrided high-speed steel excellent in corrosion resistance and seizure resistance and having high hardness and high toughness. <P>SOLUTION: The high-toughness nitrided powder-molded high-speed steel alloy excellent in corrosion resistance and seizure resistance contains, by mass, 0.85-1.20% C,≤0.5% Si,≤0.5% Mn, 3.8-6.0% Cr, 5.6-8.0% Mo, 5.1-8.0% W, 3.0-6.0% V, 0.4-1.5% N and the balance Fe with inevitable impurities, and satisfies 1.25-2.50% (C+N), 8.3-11.0% (Mo+W/2), and a corrosion resistance index, 4.7(Mo+W/2)+1.4N-Cr-2.1Mn≥32.5%. A deposited nitride comprises a vanadium-based nitride (VN or VCN including a part of carbide), and the average grain size of the nitride is 1μm or less. The area ratio of the nitride in a steel material cross-section is≥5%, and hardness is≥65 HRC. <P>COPYRIGHT: (C)2013,JPO&INPIT</p> |
