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Nowadays, biofibre-reinforced polymeric materials have become a topic of interest for researchers in the field of materials science. Not only are they low-cost to produce, but the composites have high mechanical strength properties. In some cases, these polymer composites can even replace metallic structures, making them an environmentally friendly solution. The aim of this study is to evaluate the mechanical behaviour of a polyester matrix composite material reinforced with human hair fibres. To this end, composite samples of different fibre sizes, orientations and volume fractions were produced. Subsequently, to obtain the most suitable combination, these specimens were tested under the requirements of ASTM 3039, ASTM 7264 and ASTM 5628 for tensile, flexural and impact, respectively. As a result, the first group of specimens composed of a volume fraction of 70% matrix and 30% reinforcement, with a longitudinal fibre orientation at 0°, stands out from the rest of the specimens by presenting a maximum tensile strength, a maximum flexural strength and an impact energy of 28.472 MPa, 66.24 MPa and 1.371 J, respectively. In conclusion, compared to other types of composite materials, the human hair-based composite material shows surprising potential as a promising ecological solution for applications in the furniture and automotive industry due to its high flexural strength.

The investigation of new materials that have properties such as resistance to high temperatures, wear resistance, rigidity, and low weight, involves the use of technological processes with more and more advantages. For this purpose, mechanical alloying is a widely used technique, which consist of high-energy impact between balls inside a container, where constant collisions deform and fracture the material, achieving the alloy of the particles in a solid state. This work focuses on the Vickers hardness evaluation of the copper matrix alloy with 4% Pb, 4% Sn and 4% Zn, in an oxidizing atmosphere, sintered at 800 °C and 900 °C, using milling times of 3 hours, 6 hours and 9 hours. The results show that there is a relationship between the hardness obtained, in the two groups of specimens at 800 ° C and 900 ° C, with the grinding time and the sintering temperature, among others used in the process. An average maximum hardness of 53.4 HV was obtained.