Abstract: The process of ultra - pure 316H steel for nuclear power produced by 20 t EAF-AOD-LF-VD-Φ430 mm elecrode-Φ590 mm ESR ingot-homogenizing treating-Φ310 mm forged bar flowsheet is studied by means of composition calculation ,smelting process and electroslag slag analysis, homogenization annealing process test and other methods. When the composition satisfies 0. 042% ~ 0. 047% C, ≤ 0. 55% Si, 1. 60% ~ 1. 80% Mn, 17. 00% ~ 17. 30% Cr, 12. 20% ~ 12. 40%Ni,2. 50% ~2. 60% Mo, ≤ 5 x10^-6H, ≤ 30x 10^-6 O,0. 055% ~0.070%N, the Φ430 mm electrode is remelted with CaF₂： Al₂O₃: CaO =60%: 30%: 10% slag system electroslag into Φ590 mm ESR ingot, then homogenization treated at 1 200 ~ 1 250 °C for 30 h, it can produce products to meet the standards, that is inclusion rating units- A and C being 0, B_thin 0.5,B_thick being 0,D_thin 1. 0,D_thick 0 -0. 5 and Ds being (0 ~0.5) ；ferrite content ≤ 0. 5% .

摘要： 通过对成分计算、熔炼工艺和电渣渣系分析、均质化退火工艺试验等方法，对20 t EAF-AOD-LF-VD- Φ430 mm电极Φ 590 mm ESR锭-均质处理 Φ310 mm锻材流程生产的核电用钢超纯316H工艺进行研究。当成分 (/%)满足 0.042 - 0. 047C, ≤0. 55Si, 1.60-1. 80Mn,17.00 -17. 30Cr,12. 20 ~ 12. 40Ni,2. 50 ~ 2. 60Mo, ≤ 5 x 10^-6 H,≤ 30 x 10^-6 O, 0. 055 - 0. 070N 时，将 Φ430 mm 电极釆用 CaF₂ ： Al₂O₃: CaO = 60% : 30% : 10% 渣系电渣成 Φ590 mm锭，在1 200 ~ 1 250℃ 经过30 h均质化处理后，能够生产出符合标准的产品，实物夹杂物级别为A,C 0 级,B_细 0.5级 B_粗 0级,D_细1.0级,D_粗0~0.5级,Ds (0-0.5)级;铁素体含量≤ 0.5%。