| 摘要 |
PROBLEM TO BE SOLVED: To provide an alloy steel improved in wear resistance and fatigue properties, and to provide a die with which cracks or the like caused by carbides and inclusions in a material structure are suppressed. SOLUTION: In the optional cross section parallel to the forging and rolling axes of an ingot alloy steel comprising, by weight, 0.6 to 1.0% C,≤2.0% Si,≤1.0% Mn, 3.5 to 6.5% Cr,≤5.0% Mo,≤3.5% W, 1.8 to 4.0% V, 0.1 to 5.5% Co and≤100 ppm N, and the balance Fe with inevitable impurities, the size and area ratio of the first MC type carbides contained in the alloy are controlled. Further, the size of agglomerates composed of the second MC type carbides and M<SB>6</SB>C type carbides is controlled. Further, the size and amount of nonmetallic inclusions essentially consisting of CaO are limited to the fixed values. COPYRIGHT: (C)2009,JPO&INPIT
|
