Synthesis, characterization and electrical property of nanocrystalline Cu0.5Ni0.5Ce3O5

Critical Evaluation of Relative Importance of Stress and Stress Gradient in Whisker Growth in Sn Coatings

“…The other set of studies illustrating the role of stress came from determination of stresses by measuring the curvature of coating-substrate system [10,[14][15][16][17][18][19][20]. Although this method does not elucidate the mechanism of stress evolution, its simplicity proffers simultaneous measurement of residual stress and the whisker density in real time.…”

“…Although this method does not elucidate the mechanism of stress evolution, its simplicity proffers simultaneous measurement of residual stress and the whisker density in real time. Thus, a direct correlation between the stress state and the whisker growth rate could be established, wherein it has been shown that stress in Sn coatings rapidly approached the maximum compressive stress and due to the whisker growth, the stress became tensile or saturated at a smaller compressive value [10,14,[16][17][18][19][20]. Curvature measurement techniques also showed the efficacy of post deposition "baking" of the coating at 150 ºC for 1 h [9] as well as alloying Sn with Pb [14,17,18] in preventing the build-up of compressive stress in the Sn coatings, eventually resulting in whisker-free Sn coatings.…”