| 摘要 |
<p>A weld metal of high strength Cr-Mo steel is provided, wherein the weld metal can satisfy the requirements of improvement in toughness and temper embrittlement resistance of weld metals in heat resistant vessels of Cr-Mo low alloy steel, and is excellent in the balance of heat resistance(high temperature strength), SR cracking resistance, toughness, and temper embrittlement resistance. As a weld metal of a high strength Cr-Mo steel formed by shielded metal arc welding, the weld metal comprises: 0.04 to 0.10 mass% of C, 0.15 to 0.5 mass% of Si, 0.5 to 1.0 mass% of Mn, 2.00 to 3.25 mass% of Cr, 0.9 to 1.2 mass% of Mo, 0.01 to 0.03 mass% of Nb, 0.2 to 0.7 mass% of V, not more than 0.003 mass% and more than 0 mass% of B, 0.02 to 0.05 mass% of O, and the balance of Fe and inevitable impurities, wherein a residue extracted by electrolytic extraction from only an unaffected zone of the weld metal comprises precipitated Cr in a Cr content of not more than 0.3 mass%, and precipitated Nb in a Nb content of not less than 0.005 mass%. The inevitable impurities comprise Cu and Ni in a Cu content of not more than 0.05 mass% and a Ni content of not more than 0.05 mass% respectively. The inevitable impurities comprise P and S in a P content of not more than 0.012 mass% and a S content of not more than 0.012 mass% respectively.</p> |
