# Manufacturing Technology and Mechanical Properties of Novel Pre-Impregnated Coatings as Applied to FRP “Sandwich” Composites

## TL;DR

This paper introduces new pre-impregnated coatings for composites, showing their flexibility and mechanical performance in various applications.

## Contribution

The novelty lies in the structure of pre-impregnated coatings combining functional and backing layers for enhanced mechanical performance.

## Key findings

- Five types of pre-impregnated coatings showed failure force values between 24.61 N and 28.73 N in tensile tests.
- Coatings applied to composites maintained integrity under high flexural deformation in three-point bending tests.
- Adhesion values ranged from 0.95 MPa to 1.57 MPa, indicating strong bonding with substrates.

## Abstract

This article presents the manufacturing technology and mechanical properties of innovative pre-impregnated coatings (PCs). The base materials for PC are powders of metal oxides, non-metals, minerals and thermoplastic non-wovens. PC can be used in the manufacture of composites by methods such as vacuum infusion, autoclave curing or hand lamination. This is possible due to the novel PC structure consisting of a functional layer (FL) and a backing layer (BL). PCs are flexible so that they can be used on curved surfaces. In this work, five types of PC were subjected to a uniaxial tensile test. Depending on the powder used, failure force values ranging from 24.61 N to 28.73 N were obtained. In the next step, the pre-impregnated coatings were applied as a coating in “sandwich” composites made by vacuum infusion, which were subjected to three-point bending (3-PB) and adhesion tests. 3-PB tests proved that the coating remained integral with the substrate, even under high flexural deformation, while the adhesion achieved was in the range of 0.95 MPa to 1.57 MPa. PC can be used in many engineering products, e.g., for the coating of façade panels, roof tiles, automotive parts or rail vehicles, etc.