Study on Electropolishing Conditions for 650 MHz Niobium SRF Cavity

TL;DR

This study investigates how varying electropolishing parameters affect the surface quality of 650 MHz niobium SRF cavities, aiming to optimize processing conditions for improved cavity performance.

Contribution

It systematically analyzes the impact of EP parameters like cathode surface area, temperature, and voltage to optimize surface quality of niobium SRF cavities.

Findings

Optimized EP parameters improved surface smoothness.

Identified key factors influencing surface roughness.

Enhanced cavity performance potential.

Abstract

The PIP II linear accelerator includes different types of niobium SRF cavities including 650 MHz elliptical low (0.61) and high (0.92) beta cavities. The elliptical cavity surface is processed with the electropolishing method. The elliptical cavities especially the low-$\beta$ 650 MHz cavities showed a rough equator surface after the EP was per-formed with the standard EP conditions. This work was focused to study the effect of different EP parameters, including cathode surface area, temperature and voltage, and optimize them to improve the cavity surface.