Documents published in Scipedia

• Welding thermoplastic composites using resistive heating: tooling design, joining procedure and demonstrator manufacturing

  A. Iriarte Legarreta, M. Segura, S. García-Arrieta, . R.Mezzacasa

  Materiales Compuestos (2025). Vol. 09 - Comunicaciones MatComp25 (2025), (Núm. 1 - Fabricación y Aplicaciones Industriales), 35

  
  

  Abstract

  Thermoplastic welding technology is a long-established technology in the industry where the efficiency of the welded joint can be approached to the properties of the base material by fast, automated and reversible joining. The joining of two thermoplastic compounds can be done by fusion bonding and reconsolidation of the pieces in the joining line. The most promising fusion bonding techniques, and nowadays with more presence in the aeronautical sector, are resistance welding, induction welding, ultrasonic welding and laser welding. Among these methods, the advantage of resistance welding is that the heat is produced exactly at the interface to be welded, avoiding unwanted heating in other parts of the piece. This method is based on the application of an electrically conductive implant between the two parts to be welded under pressure that generates heat with the passage of current. The objective of this work was to develop a resistance welding system for the joining of a thermoplastic composite assembly. A demonstrator of a representative element of the aeronautical sector was manufactured in carbon fiber and PPS composite material consisting of a skin to which two L-shaped brackets made of the same material as the skin were welded. The welding process carried out and the electrical and thermal parameters obtained show the repeatability of this process. This technology could be easily scalable for the welding of larger elements and different geometries.

  Abstract
  Thermoplastic welding technology is a long-established technology in the industry where the efficiency of the welded joint can be approached to the properties of the base [...]

  • 18
  •  read

• Fast and efficient manufacture of carbon fiber aeronautical preforms by using direct resistive heating

  A. Iriarte Legarreta, M. Segura, R. Mezzacasa, B. Canflaca

  Materiales Compuestos (2022). Vol. 07 - COMUNICACIONES MATCOMP21 (2022), (Núm. 2 - Aplicaciones Industriales - Caracterización), 172

  
  

  Abstract

  The manufacture of preforms for composite structures is predominantly carried out in large hot drape forming facilities. However, these conventional heating sources are very inefficient since a large part of the heat provided is transferred to the molds in which the preforming process is carried out. This implies long heating and cooling times. In the current context in which it is essential to reduce the carbon footprint of each component, the reduction in the energy needed and in the cycle times to obtain competitive processes is fundamental. In this context, Tecnalia has developed an advanced preforming cell for the manufacture of dry fibre preforms for RTM or infusion components by applying direct resistive heating. The application of a current directly on the material to be processed has the advantage of avoiding the heating and cooling of molds and obtaining results in a much faster and more efficient way than with the methods traditionally used until now. The application of heating only to the preform guarantees the obtaining of much shorter cycle times, and a reduction in energy consumption of up to 90%. This results in a reduction in the cost of the process associated with lower energy consumption and shorter cycle time. The resistive preforming offers results of a quality of the preforms similar to that of conventional hot drape forming technology, being also a repetitive process, which has been validated by impregnating preforms tested under flight conditions.

  Abstract
  The manufacture of preforms for composite structures is predominantly carried out in large hot drape forming facilities. However, these conventional heating sources are very [...]

  • 13
  •  read