| 摘要 |
<p>PURPOSE:To evaluate solder wettability quickly and nondestructively for each electric connecting terminal coated with low melting point metal. CONSTITUTION:Under a state where a sample 5, i.e., an electric connecting terminal, is irradiated with laser beam 2 to heat a low melting point metal coating layer, temperature and optical reflectance at a point irradiated with laser beam are measured through a thermometer 11 and a detector 9, respectively. Coating layer at a point irradiated with laser beam thermally fuses eventually. The fusion causes abrupt variation of optical reflectance at the point irradiated with laser beam and when the temperature at that point of time is compared, as the melting point of the coating layer, with the inherent melting point of the low melting point metal, solder wettability can be evaluated easily.</p> |
