EFFECT OF FRICTION WELDING ON CHARACTERISTICS OF PURE TITANIUM/A5083 ALUMINUM ALLOY JOINT

Report 2: Metallurgical Properties of Joint Interface Region

抄録

The metallurgical properties of the interface regions of as-welded dissimilar friction joints between pure titanium (Ti) and aluminum-magnesium alloy (A5083) base materials were investigated. Hardness values in the region about Imm from the joint interface were higher than those in the bulk Ti and A5083 substrates. No transition layer was observed at the joint interface using optical microscopy, X-ray diffraction analysis and scanning electron microscope (SEM) including EDS-analysis. However, transmission electron microscope (TEM) observation of the joint interface region confirmed that intermetallic phases with thickness of 200nm or less were produced during joining. The intermetallic phases were estimated to be Mg₂Al₃, Al₃Ti and τ-Al (Ti₂Mg₃Al₁₈) by TEM-EDS analysis. It was concluded that the selection of joining parameters that promotes the formation of thin transition and intermetallic layers produces dissimilar joints with satisfactory mechanical properties.