EFFECT of TEMPERAUTRE on PACK SILICONIZING of Ti6Al4V ALLOY

Öz

This study aims to investigate the temperature effects on silicide coating formed by pack siliconizing method on Ti6Al4V subsrate. Pack siliconizing process was conducted out for 2h at 1000°C, 1100°C, 1200°C, in vacum atmosphere, by using Si as Si source, Al2O3 powder as filler and NH4Cl as an activator. The presence of the formed phases such as Ti5Si3, TiSi, TiSi2 on coating, and non-stoichiometric Al203 compound from the pack mixture was actualized by X-ray diffraction analysis (XRD). It was obeserved that the silicide coating on Ti6Al4V substrate is compact, dense and the coating thickness varies between 10.5-30.4 μm depending on the treatment temperature. The morphological feautres of the coating and dispersion of the elements in the silicide layer was examined by using electron microscope (SEM) and elemental analysis (EDS). Hardness of silicide layer measured by Vickers method and determined that the hardness ranges between 1170 Hv0,025 to 1450 HV 0,025 .

Anahtar Kelimeler

• Pack cementation
• pack siliconizing
• diffusion coating
• Ti6Al4V
• silicide coating

Kaynakça

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