CORROSION PROTECTION OF 13CRMO-44 HEAT-RESISTANT FERRITIC STEEL BY SILICON AND CERIUM ION-IMPLANTATION FOR HIGH-TEMPERATURE APPLICATIONS

The influence of the ion implantation of 1 x 10(15) ions/cm(2) of sili con and 1 x 10(14) ions/cm(2) of cerium at 150 keV on the oxidation be haviour of a 0.80%Cr-0.40%Mo heat-resistant 13CrMo 44 ferritic steel w as studied at 973 K in air for 144 h under isothermal conditions. The implanted surfaces and the corrosion products formed on the surface we re characterized by means of AES, SEM and XRD. Theoretical calculation s were performed by TRIM96 computational code. From the present study it was concluded that silicon enhances selective oxidation of chromium and a more protective oxide scale was found to grow. However, cerium confers a detrimental effect by cracking and spalling of the oxide lay ers formed at high temperature. (C) 1998 Elsevier Science S.A. All rig hts reserved.