Preparation of Ni_xTi_y compound via Ni plating followed by thermal treatment of Ti powder

ABSTRACT

In this research, Ni_xTi_y compound was prepared by thermal treatment of Ni-plated Ti powder. For this purpose, Ti powder was plated in an electroless Ni bath for various times (120, 225, 300, and 720 min). Hydrazine hydrate was used as a reductant for the deposition of pure Ni on the Ti particles. The plated powder (225 min) was heat treated under argon atmosphere to achieve Ni_xTi_y powder. Finally, the heated/plated powder was pressed by CIP followed by sintering at 980°C for prepare the Ni_xTi_y bulk sample. The plated powders as well as sintered one were characterized using scanning electron microscopy, energy dispersive spectrometer, X-ray fluorescence, X-ray diffraction and differential scanning calorimetric. The NiTi₂, NiTi, and Ni₃Ti phases were detected in the XRD patterns of heated/plated Ti powder. According to DSC data, the heated/plated Ti powder showed reversible martensitic transformation at temperature range of −38.0°C to +38.1°C, while sintered/heated/plated Ti powder displayed reversible transformation at temperature range of 16.0°C–15.4°C.

KEYWORDS:

• Heat treatment
• Ni plating
• Ni_xTi_y compound
• sintering

Acknowledgments

This work was supported by South Tehran Branch Islamic Azad University for the research project entitled “Synthesis of Ni-Ti binary powder and Cu-G composite powder by electroless plating.”