Introduction

Method for making a joint of reinforced composite materials with a polymeric matrix, for example composites with a thermosetting or thermoplastic matrix. The proposed process, which can be standardized and easily automated, guarantees greater sealing results than those obtainable with the techniques of the known art currently in use. Fiber-reinforced materials are gaining increasing interest in numerous industrial sectors; however, a significant criticality is their junction with other materials. Univaq researchers have developed an innovative thermomechanical joining process for reinforced materials, allowing to avoid adhesive and mechanical joins, characterized by numerous limitations.

Technical features

Compared to the former, no thermosetting adhesives are applied which involve uncertainty on performance in the medium-long term and are relatively fragile, the process is faster, resulting in a duration of less than 10s, as well as having a low environmental impact, as no pre-treatment of the surfaces with chemical solvents. Compared to mechanical joints, the process allows for distributed (non-punctual) connections to be made with a better distribution of stresses, the absence of external elements that lead to an increase in costs, as well as protruding elements with respect to external surfaces. The process allows a significant reduction in the weight of the component, and greater ease of repair of the joint: once damaged, the joint can be restored without the need to disassemble the assembly. TRL 3: has been tested in the laboratory for use with metallic materials, such as magnesium or titanium alloys, and polymeric, thermosetting or thermoplastic materials.

Possible Applications

• Production of multi-material hybrid structures (HS), used in a wide range of applications, in particular in the fields of: transportation, electronics, civil, biomedical.

Advantages

• High mechanical characteristics;
• Simple and fast process;
• Process feasible even when one side of the joint is difficult to access;
• Disassembly of the joint by a simple heating operation;
• In case of damage, the joint itself can be restored by a simple heating and compression operation;
• Absence of problems caused by a different thermal contraction of the materials.