ABSTRACT
Inspection of Figure Jd representing the Sn particle distributions within the assprayed coating and those annealed at 300°C for I hour and 5 hours initially shows that the Sn particle number decreases with increasing particle area, tending to zero for an area value of greater than l.OJ.!m2. The histogram shows that the number of sub-micron Sn particles with area between 0.1 - 0.3Jlm2 within the same volume decrease slightly after I hour annealing at 300°C, as compared with the as-sprayed coating, but decreases significantly after 5 hours of annealing. For Sn particles of area between 0.3-0.55J.!m2, there is little difference in the decrease of the number of Sn particles within these annealed coatings. For the Sn particles with area greater than 0.55Jlm2, the number of Sn particles slightly increases after 5 hours of annealing. These results indicate that the sub-micron Sn particles tend to coalescence and merge with the larger Sn particles as the annealing time is increased.
