Fe/Al异种金属扩散界面区的显微组织  

Microstructure in interface zone of diffusion-bonded joint of Fe/Al dissimilar materials

作　　者：王敬[1] 尹小燕[1] 杨帅[1] 

机构地区：[1]江苏科技大学材料科学与工程学院,江苏镇江212003

出　　处：《焊接技术》2011年第12期15-17,5,共3页Welding Technology

摘　　要：铝及铝合金/钢焊接接头结合面上易产生Fe-Al脆性金属间化合物,使接头性能下降。而Fe,Al为主要代表元素,为研究方便,故采用真空扩散焊技术对Fe/Al异种材料进行焊接。利用扫描电镜(SEM)、电子背散射衍射仪(EBSD)及显微硬度计对扩散界面附近的显微组织结构、元素分布及扩散区硬度分布进行试验研究。结果表明:Fe/Al异种材料真空扩散焊在不同保温时间,加热温度Tp=560℃,压力强度p=1 MPa的条件下获得的焊接接头,接头界面区形成了暗灰色的新相化合物层,即生成了FeAl2,Fe2Al5等脆性金属间化合物,并随着保温时间的延长,扩散反应层厚度随之增加;扩散反应区显微硬度(范围为HV626～HV1 078)明显存在3个不同的硬度分布区。During the bonding between aluminous or aluminum alloy and stainless steel,the brittle Fe-Al intermetallics,which lead to performance degradate,were easily produced at the interface.As the main representative elements,Fe and Al were bonded with vacuum diffusion bonding technology in order to conveniently research.The microstructure,distribution of elements and micro-hardness of the Fe/Al diffusion bonded joint were studied by scanning electron microscope(SEM),electron back scattering diffraction(EBSD)and micro-hardness test.The diffusion bonding parameters were the heat temperature 560 ℃ and the pressure 1 MPa at the different holding times.The experiment results indicated that the new dim-gray compact phases were FeAl2,Fe2Al5,etc,which were formed at the interface region of Fe/Al diffusion bonded joint.With the holding time extending,the diffusion reaction layer thickness increased.There were three different hardness distribution in the diffusion reaction zone.

关 键 词：真空扩散焊 显微组织 反应层 Fe—Al金属间化合物 

分 类 号：TG453.9[金属学及工艺—焊接]