The influence of heat treatment regimes on the mechanical properties of unsaturated polyester resin composites reinforced with fiberglass for agricultural machinery working parts

Background. In modern agriculture, enhancing the durability and efficiency of machinery components, such as soil tiller blades, is crucial for improving productivity and sustainability. In this context, the study of advanced materials like glass fiber-reinforced unsaturated polyesters presents a relevant challenge.

Purpose. The aim of this research was to experimentally investigate the possibility of improving the properties of this composite material for the production of agricultural machinery parts.

Materials and Methods. For the study, samples were made from glass fiber-reinforced unsaturated polyester with various proportions of added components. The samples were divided into two groups: one group underwent thermal treatment, while the other remained untreated. Mechanical property testing was conducted using standard tensile tests to determine the values of tensile strength. Observations were also made regarding changes in mechanical properties under prolonged heat exposure.

Results. The results showed that samples with optimized proportions of added components, without direct thermal treatment, exhibited lower tensile strength values compared to samples that underwent thermal treatment. However, with prolonged application of heat over a relatively long period, the strength values began to decrease significantly. This indicates that extended heating leads to increased brittleness of the polyester composition and enhances reactions occurring within the mixture, negatively affecting the strength properties of the material under investigation.

Conclusion. The obtained data indicate a complex relationship between thermal treatment and the strength characteristics of the material. While thermal treatment may initially improve properties, prolonged heat exposure can lead to structural degradation and reduced strength. These results highlight the importance of optimizing technological processes in the production of soil tiller bladeto achieve a balance between enhancing mechanical properties and preventing undesirable changes associated with thermal treatment. Tensile test results showed that proportions approved for the production of glass fiber-reinforced unsaturated polyester soil tiller blade without direct thermal treatment lead to lower tensile strength values compared to thermally treated samples. This suggests incomplete curing of the mixture, resulting in a reduction of the studied mechanical properties. Furthermore, prolonged heat exposure for a relatively long duration (up to 72 hours) caused a significant decrease in tensile strength values. This indicates that prolonged heating enhances the reactions occurring within the mixture, leading to increased brittleness of the polyester composition and adversely affecting its strength characteristics. The study demonstrated that the correct choice of component proportions and thermal treatment regimes is critical for achieving optimal mechanical properties of glass fiber-reinforced unsaturated polyesters. These results could serve as a foundation for further research and development in materials science aimed at creating more efficient and durable materials for use in agricultural machinery.