The effect of surface preparation on high temperature oxidation of Ni, Cu and Ni-Cu alloy

TL;DR

This study investigates how different surface preparation methods, especially sand-blasting, affect the high temperature oxidation behavior of nickel, copper, and their alloy, revealing that surface roughness and contamination influence oxidation kinetics and oxide layer formation.

Contribution

It provides new insights into how surface preparation techniques alter oxidation mechanisms and oxide morphology in Ni, Cu, and Ni-Cu alloys at high temperatures.

Findings

Sand-blasting increases surface roughness and introduces alumina particles.

Surface preparation affects oxidation kinetics and oxide layer thickness.

Sand-blasted samples form mixed oxides with alumina intrusions.

Abstract

In the present paper, the analysis of polishing, grinding and sand-blasting processes on oxidation behavior of nickel, copper and nickel-copper alloy has been investigated. Surface roughness has been measured using two methods: by contact profilometer and by fractal analysis. It has been proved that sand-blasting process influences the surface roughness the most but also contaminates the surface with alumina particles. The oxidation tests were performed in thermogravimetrical furnace. The obtained mass gain plots, SEM microphotographs of cross-sections and SEM EDS analysis of the samples prove that surface preparation changes oxidation kinetics morphology of the polished and ground samples does not vary significantly after oxidation at investigated temperatures, but differences in oxide layer thicknesses and mass gains were observed. Oxidized sandblasted samples reveal that increased surface roughness and alumina intrusions change the oxidation process mixed Al (Ni, Cu or Ni-Cu) oxide is formed and separate Al2O3 particles are visible. The results prove that surface preparation influence high temperature oxidation of the samples by promoting new diffusion mechanism.