Characterisation of intermetallics and mechanical behaviour in the reaction between SnAgCu and Sn-Pb solder alloys

摘要: Due to the imminent wide-spread introduction of Pb-free solders, materials properties, manufacturing and reliability solder joints are currently being investigated in electronics packaging community. The interactions new alloys with other particular concern order understand thereby enable optimisation control processes for reliable products. In transition period from Sn-Pb soldering, existing products that remain market, or customers, is an issue when they have be repaired solders. complete elimination Pb specified legislation has account contamination inevitable rework, repair technology upgrades. As such, a number technical problems connection mixing exist, including: (1) Uncertainty resulting microstructure its properties; (2) effect unknown compositions structures on reliability; (3) Critical tolerable levels some elements can permitted applications; (4) relative content formation morphology intermetallic phases. this paper thermodynamic calculations presented studied multicomponent material behaviour possible precipitates during reactions between Sn-Ag-Cu alloys. Two relevant current industrial interests, namely Sn-3.9Ag-0.6Cu (known as '405 alloy' Europe North America), Sn-3.0Ag-0.5Cu '305' alloy Asia), were selected react different eutectic Sn-37Pb solder. also presents experimental work characterized intermetallics mechanical following reaction SnPb phase identification was by optical microscopy scanning electron (SEM), latter featuring back scattered diffraction (EBSD) technique offers details orientation at nanoscales. Nanoindentation, which suitable ultra-fine complex microstructures small volumes, used investigate micromechanical including hardness, elastic modulus creep, both ambient elevated temperatures.