23Cr-l8Ni-3Cu-1.5W-0.4Nb-0.2N steel with improved creep rupture strength and good corrosion resistance has been developed for USC boilers. The addition of 3% Cu contributes to improving creep rupture strength remarkably, which is due to fineCu-rich phase precipitation coherent to austenitic matrix during creep. W mainly contributes to solid solution strengthening. The effect of W on creep rupture strength has been compared with that of Mo. It has been revealed that excellent creep rupturestrength of W containing steel is accomplished by suppression ofσ phase precipitation and carbides coarsening. The 10{sup}5 h extrapolated rupture strength of this steel at 700°C is estimated to be 91 MPa. The Charpy impact value of this steel afteraging at 700°C for 3000h is about 55J/cm{sup}2. It is thus concluded that the newly developed 23Cr-l8Ni-3Cu-1.5W-0.4Nb-0.2N steel shows excellent creep rupture strength and microstructural stability and hence can be used for superheater or reheater tubesin USC boilers.
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机译：为USC锅炉开发了具有改善的蠕变破裂强度和良好耐腐蚀性的23Cr-L8Ni-3Cu-1.5W-0.4NB-0.2N钢。添加3％Cu有助于显着提高蠕变破裂强度，这是由于在蠕变期间对奥氏体基质相干的FineCu的相沉淀。 W主要有助于加强固体溶液。将W对蠕变破裂强度的影响与MO的影响进行了比较。已经揭示了通过抑制σ相沉淀和碳化物粗化来实现优异的W含有钢的蠕变爆发。该钢在700℃下的10 {Sup} 5 H外推破裂强度估计为91MPa。该钢的夏比冲击值在700°C下进行3000h，约为55J / cm {sup} 2。因此得出结论，新开发的23Cr-L8Ni-3Cu-1.5W-0.4NB-0.2N钢显示出优异的蠕变破裂强度和微观结构稳定性，因此可用于过热器或再热饮料管素USC锅炉。
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