Review Advanced Thermoplastic Composite Manufacturing by In-Situ Consolidation: A Review Isabel Martin 1, Diego Saenz del Castillo 1 , Antonio Fernandez 2 and Alfredo Güemes 2,* 1 FIDAMC, Foundation for the Research, Development and Application of Composite Materials, Avda. Rita Levi Montalcini 29, Tecnogetafe, Getafe, 28906 Madrid, Spain; Maria-Isabel.Martin@fidamc.es (I.M.); Diego.Saenz@fidamc.es (D.S.d.C.) 2 E.T.S.I. Aeronáutica y del Espacio, Universidad Politécnica de Madrid, Pza. de Cardenal Cisneros 3, 28040 Madrid, Spain;
[email protected] * Correspondence:
[email protected] Received: 23 August 2020; Accepted: 10 October 2020; Published: 13 October 2020 Abstract: This article provides an overview of the evolution of the in-situ consolidation (ISC) process over time. This evolution is intimately linked with the advancements in each of the steps of the ISC manufacturing process, is additive in nature, and is limited by the orthotropic nature of composite materials and the physicochemical behavior of the thermoplastic matrix. This review covers four key topics: (a) Thermal models—simulation tools are critical to understand a process with such large spatial gradients and fast changes. Heating systems once marked a turning point in the development of industrial ISC systems. Today, lasers are the most recent trend, and there are three key issues being studied: The absorption of energy of light by the material, the laser profile, and the laser focusing. Several approaches have been proposed for the distributed temperature measurements, given the strong temperature gradients. (b) Adhesion—this refers to two subsequent mechanisms. In the first place, the process of intimate contact is one by which two surfaces of thermoplastic pre-impregnated composite materials are brought into contact under pressure and temperature.