Evolution of W/Fe interfacial microstructure and shear performance for W/Fe/RAFM-steel joint in process of normalizing and tempering heat treatment

doi:10.16568/j.0254-6086.202103008

Abstract

Abstract: Normalizing and tempering heat treatment were carried out for the HIP bonded W/Fe/RAFM-steel joints to recover the microstructure and properties of the RAFM-steel. The evolution of W/Fe interfacial microstructure were analyzed by Electron Probe Micro-analyzer (EPMA) and Grazing Incidence X-ray Diffraction (GIXRD), the evolution of bonding performance for the joint was characterized by Shear Test and Scanning Electron Microscope (SEM). The results showed that after normalizing heat treatment, the C element in RAFM-steel diffused into W/Fe interface and the content of W and C in Fe₂W phase was increased, which increased the shear strength of the joint. While the strengthening of Fe interlayer led to a shorter shear displacement. After tempering heat treatment, a W/Fe₂W/Fe3W3C/Fe interfacial structure was formed at W/Fe interface. As its composition of Fe₂W phase and strength of Fe interlayer were almost the same with the HIP bonded joint, the shear performance of the joint at room temperature was almost the same with the HIP bonded joint.

Key words: Tungsten, RAFM-steel, Fe Interlayer, HIP diffusion bonding

摘要： 对热等静压(HIP)扩散焊制备的W/Fe/RAFM钢接头进行了正火和回火处理，以恢复其中RAFM钢的组织和性能。采用电子探针微分析器(EPMA)和掠入射X射线衍射(GIXRD)对W/Fe界面组织的演化进行了分析，采用剪切测试和扫描电镜(SEM)对接头连接性能的演化进行了测试和分析。结果表明，正火处理后，RAFM钢中的C 元素扩散到了W/Fe界面，Fe₂W相中W和C元素含量增加，这导致了接头剪切强度增加，而纯铁中间层强度的增加则导致了接头剪切位移下降。回火处理后，W/Fe界面形成了W/Fe₂W/Fe₃W₃C/Fe的界面结构，回火态接头Fe₂W相的成分和纯铁中间层强度与HIP态接头基本相同，因此回火态接头室温剪切性能基本与HIP态接头一致。

关键词: 钨；RAFM钢；纯铁中间层；热等静压扩散焊接

CLC Number:

TL62+7

HUANG Pan, WANG Yi-ming, CHEN Ji-ming, WANG Ping-huai . Evolution of W/Fe interfacial microstructure and shear performance for W/Fe/RAFM-steel joint in process of normalizing and tempering heat treatment[J]. Nuclear Fusion and Plasma Physics, 2021, 41(3): 240-246.

黄攀, 王一鸣, 谌继明, 王平怀. 正火和回火处理过程中W/Fe/RAFM钢接头 W/Fe界面组织和剪切性能的演化[J]. 核聚变与等离子体物理, 2021, 41(3): 240-246.

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