Surface segregation of Sn, In and Bi in high purity aluminum annealed at various temperatures ranging from 423 K to 723 K for 72 ks was studied by Rutherford back scattering spectroscopy（RBS）and transmission electron microscopy（TEM）. The strongest segregation was observed in Al containing Sn, In and Bi annealed at 523 K, 623 K and 723 K, respectively. Concentrated positions were different depending on elements; Sn and Bi were at the interface between aluminum oxide and matrix, but In was in aluminum oxide. The empirical rule for degree of surface segregation（surface segregation composition／foil composition）was roughly depending on the inverse of solid solubility, i.e., stronger segregation occurred in less solubility element.

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In this study, to improve the accuracy of scanning induction hardening simulations, an induction hardening test using the round bar of the chromium molybdenum steel, standardized as JIS-SCM440 in Japan, and the water spray cooling test were performed. Also, the cooling conditions of the scanning induction hardening were verified in detail. The heat transfer coefficient curves of the injection and laminar regions were estimated by using the cooling data from the water spray cooling test. And the induction hardening simulation was carried out under the thermal boundary condition in consideration of the rebound phenomenon of the sprayed water from the specimen surface. The result showed that the both the simulation and the measured results were in good agreement.

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