稀土Dy在等离子W-Mo-Dy共渗中的动力学行为

Dynamic Behavior of Rare Earth Dy in Plasma W-Mo-Y Co-diffusion

摘要:

采用等离子渗金属技术在碳钢表面形成W-Mo共渗层和W-Mo-Dy共渗层，利用origin数值软件、菲克第二定律、阿累尼乌兹公式分析W、Mo、Dy在共渗中的动力学行为。结果表明：在表面0～5 μm处，由于稀土Dy的加入使W、Mo原子的扩散系数分别提高了0.94倍和0.62倍，在80 μm处，W-Mo-Dy共渗较W-Mo共渗W、Mo原子的扩散速度分别提高了2.87倍和1.07倍；稀土Dy的加入使表面5 μm处的W、Mo原子的扩散激活能分别降低7.13和5.19 kJ/mol，使得90 μm处W、Mo原子的扩散激活能分别降低32.20和10.83 kJ/mol。在相同工艺条件下，W-Mo-Dy共渗表层控制扩散的主要因素是空位浓度，在次表面稀土Dy可降低W、Mo的扩散激活能

Abstract:

A plasma surface metallurgy technique was used on the surfaces of carbon steel to form W-Mo alloying layer and W-Mo-Y alloying layer. Dynamic behavior of W, Mo and Dy was investigated by origin software, Fick’s second law and Arrhenius formula. Results show that Dy addition increases the diffusion coefficient of W and Mo by 0.94 times and 0.62 times, respectively in the diffusion layer from surface of 0~5 μm while increases the diffusion rate of W and Mo by 2.87 times and 1.07 times, respectively in the diffusion layer from surface of 80 μm. However, the Dy addition decreases the activation energy of diffusion of W by 7.13 kJ/mol and Mo by 5.19 kJ/mol from surface of 5 μm, while it decreases the activation energy of diffusion of W by 32.20 and Mo by 10.18 kJ/mol from surface of 90 μm. Under the same process condition, the main influence factor of diffusion in W-Mo-Dy co-diffusion layer is vacancy concentration. Dy decreases activation energy of diffusion of W and Mo in the subsurface