This study investigated the microstructure and mechanical properties of the wide-gap
region brazed with various powder mixing ratios of additive powder (IN738) to filler metal powder
(DF4B). The wide-gap brazing process was carried out in a vacuum of 2×10-5 torr at 1230°C for 1 hr.
The microstructure of the brazed region was analyzed by FESEM and AES. The wide-gap region
brazed with 60wt.% IN738 additive powder and 40 wt.% DF 4B filler metal powder had a
microstructure consisting of Ni solid solution + γ' and (Cr, W)2B. The fracture strength of the
wide-gap region brazed with 60 wt.% IN738 additive and 40 wt.% DF 4B powder was as high as 832
MPa at room temperature. It was found that the (Cr, W)2B and pores in the brazed region are
important microstructural factors affecting the mechanical properties of the wide-gap brazed region.
Study on the Microstructure and Mechanical Properties of Butt
GMAW Al/Fe Dissimilar Joints using Pure Copper Filler Metal
