基于热力学模拟计算的CLF-1钢改良设计  

Improved Design of CLF-1 Steel Based on Thermodynamic Simulation

作　　者：杨栋天 熊良银[1,2] 廖洪彬 刘实 ANG Dongtian;XIONG Liangyin;LIAO Hongbin;LIU Shi(Special Alloy Research Department,Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,China;School of Materials Science and Engineering,University of Science and Technology of China,Shenyang 110016,China;Southwestern Institute of Physics,Institute for Fusion Science,Chengdu 610225,China)

机构地区：[1]中国科学院金属研究所特种合金研究部,沈阳110016 [2]中国科学技术大学材料科学与工程学院,沈阳110016 [3]核工业西南物理研究院聚变科学所,成都610225

出　　处：《材料研究学报》2023年第8期590-602,共13页Chinese Journal of Materials Research

摘　　要：使用Thermo-Calc软件计算CLF-1钢中平衡析出相的成分和含量,研究了各平衡相中的元素分布随温度变化的规律、主元素对各相析出量、析出温度的影响,以及元素在各平衡相之间分配的规律;用透射电子显微镜(TEM)表征了添加Ti元素后析出相的尺寸和数密度。热力学计算结果表明:TaC相中C的分配量只占M23C6中C分配量的约3.3%。C元素的不均匀分配,是CLF-1钢中MX相析出量较低的主要原因之一;在不引入其它强碳化物形成元素的情况下,无法用提高C含量的方式使MX相中C的分配量提高;Cr含量的提高会降低TaC的析出温度,因此其含量不宜超过8.8%;W含量的提高会降低MX析出量,因此不宜超过1.5%;Mn元素对各析出相都没有显著的影响;N含量不宜超过0.02%;在CLF-1钢中添加0.2%Ti可使MX相在650℃的析出量提高9倍,C的分配量提高15倍。实验结果表明:0.2%的Ti元素可使M23C6的数密度降低21.5%,平均尺寸减小20 nm,并使MX相数密度提高4.7倍。这些结果,有力地验证了Ti元素对MX相析出的促进作用。The composition and quantity of the equilibrium precipitated phases in CLF-1 steel were calculated by means of Thermo-calc software.The variation of element distribution in each equilibrium phase with temperature,the influence of main elements on the precipitation amount and temperature of each phase,and the partition of elements among equilibrium phases were investigated.Meanwhile,the size and number density of the precipitated phases were characterized by transmission electron microscopy(TEM).Thermodynamic calculation results show that the partition amount of C in TaC phase only accounts for about 3.3%of that in M23C6.The heterogeneous partition of C is one of the main reasons for the low MX phase precipitation in CLF-1 steel.Without introducing other strong carbide-forming elements,the partition amount of C in MX phase cannot be increased by increasing the C content.The increase of Cr content will reduce the precipitation temperature of TaC,so the Cr content should not exceed 8.8%.The increase of W content will reduce the amount of MX precipitation,so it should not exceed 1.5%.Mn has no significant effect on the amount of every precipitated phase.Finally,N content should not exceed 0.02%.The addition of 0.2%Ti in CLF-1 steel can increase the precipitation amount of MX phase at 650℃by 9 times,and increase the partition amount of C by 15 times.The experiment result shows that:the addition of 0.2%Ti can reduce the number density of M23C6 by 21.5%,reduce its average size by 20 nm,and increase the number density of MX phase by 4.7 times.These results strongly verified the promoting effect of Ti element on MX phase precipitation.

关 键 词：材料科学基础学科 相图与相变 CLF-1钢改良 Thermo-Calc计算 MX相 元素分配量 

分 类 号：TG142[一般工业技术—材料科学与工程]