Plasma surface interaction of nitrogen plasma on AISI 304 steel

ABSTRACT

An energetic nitrogen plasma stream of a pulsed plasma accelerator was used to study plasma matter interaction with stainless steel 304 samples. The high velocity plasma stream was allowed to interact with the samples at different plasma energy densities. The exposed samples were analysed using X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive X-ray (EDX) and Micro-hardness tests. The SEM micrograph shows the formation of fine particles, melting, cracking and evaporation of sample surface at different plasma energy densities. Tentative threshold values of these phenomena were estimated from experimental observations. The XRD result doesn’t predict the formation of nitrides but confirms the occurrence of stress and relaxation in the lattice. The hardness value decreases with an increase in energy density and number of exposures. The EDX results show deposition of eroded particles and envisage possibility of creation of vacancy defects.

KEYWORDS:

• Coaxial pulsed plasma accelerator
• plasma stream
• plasma-material interaction
• fusion
• stainless steel-AISI304

Acknowledgement

The authors also thank Mr. K. Kalita for assisting the laboratory activities. The authors are also grateful to CSIR-NEIST, Jorhat for extending electron microscopy and X-ray Diffraction facilities. Moreover, the authors acknowledge the Material Science Division, IIT Guwahati for allowing to carry out the hardness testing.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The authors express their sincere gratitude to the Director, Institute for Plasma Research (IPR) and Centre Director, Centre of Plasma Physics-IPR, for their valuable suggestions and financial support for the present work.