# Impact of Selected Metal Oxides on the Thermodynamics of Solid Rocket Propellant Combustion

## TL;DR

This study explores how adding metal oxides like Fe2O3 and CuO improves the combustion performance of solid rocket propellants using ammonium nitrate.

## Contribution

The novel contribution is the systematic evaluation of specific metal oxides as additives to enhance the thermodynamics and combustion efficiency of ammonium nitrate-based solid rocket propellants.

## Key findings

- Metal oxides significantly improve combustion performance of ammonium nitrate-based SRP formulations.
- XRD analysis confirmed changes in combustion residue, supporting the proposed combustion mechanisms.
- Linear combustion velocity and power output were measured to assess motor performance improvements.

## Abstract

A series of catalytic oxides (Fe2O3, CuO, ZnO, and Cu2O) were investigated as prospective additives shaping the thermal features of a model solid rocket propellant (SRP) formulation utilising ammonium nitrate as the oxidising agent. An extensive investigation of the thermal behaviour (DSC and ignition/explosion temperature studies) of the model and catalyst-bearing SRP formulations was conducted, providing insights into both the thermodynamics and mechanism of combustion of these systems. XRD analysis of post-combustion residues was used to validate the mechanistic claims, as well as to provide information about the behaviour of copper oxides in the SRP system. In addition, the linear combustion velocity was experimentally determined, and the power output was estimated from density, linear combustion velocity and DSC data, in order to assess the potential motor performance of the tested formulations. The obtained results show that the utilisation of metal oxides significantly improves the combustion performance of ammonium nitrate-based SRP formulations relative to the unmodified ammonium nitrate-based propellants.