论文部分内容阅读
为了配合20万kW供热机组汽轮机末级叶片的研制工作,本文就不同锻比、不同预先热处理制度、不同调质工艺对国内试生产的20CrllMolV(国外通常称X20CrMoV-121)钢延性断裂韧度的影响进行了探讨。研究表明,足够大的锻比、采用锻造淬火+高温回火代替普通退火作为预处理并选用低温淬火(960℃淬油)、高温回火(660℃×5h)处理,可以获得更高的J_(1c)值。分析表明,由于显著改善了这类马氏体不锈钢调质态钢中碳化物的大小与分布,是提高其强韧性的主要原因。
In order to cope with the development of the last stage blades of steam turbines of 200 MW units, the ductile fracture toughness of 20CrllMolV (X20CrMoV-121 abroad), which is produced in China, is investigated for different forging ratios, different pre-heat treatment systems and different quenching processes. The impact of the discussion. The results show that, forging ration is enough, forging quenching + high temperature tempering instead of normal annealing as pretreatment and low temperature quenching (960 ℃ quenching) and high temperature tempering (660 ℃ × 5h) can be used to obtain higher J_ (1c) value. The analysis shows that, due to the significant improvement of the size and distribution of carbides in such martensitic stainless steels, it is the main reason for enhancing their toughness.