Abstract | High purity tin samples were doped with Fe, Sb, Pb, In and Al. These impurities shifted the run-off point of the melting curve of tin by −0.75 mK (ppm wt)−1, +0.23 mK (ppm wt)−1, −0.16 mK (ppm wt)−1, −0.21 mK (ppm wt)−1 and −2.3 mK (ppm wt)−1, respectively (ppm wt denoted the mass fraction in parts million). However, 1654 ppm wt of Fe and 12.2 ppm wt of Al concentrations appear to supersaturate tin. The extra amount of these impurities then gradually precipitated as the doped samples were subjected to repeat melting. In the 10 ppm wt Fe to about 970 ppm wt Fe concentration range tin has a solid–liquid phase transformation of very narrow melting range, 6.9 mK below the tin-point. |
---|