Original Article Screen-printed nanocomposite sensors for online in situ structural health monitoring Taimoor A Khan 1 , Saad Nauman 2 , Zeeshan Asfar 3 , M Ali Nasir 4 and Zaffar M Khan 1 Abstract In this article, we have explored screen printing as a fast and reliable process for the deposition of nanocomposite layer on glass fiber-reinforced plastic (GFRP) substrate for in situ structural health monitoring. The screen-printed sensor comprised of a thermoplastic matrix (high density polystyrene) and a dispersed nanofiller (carbon nanoparticles). Notches of different sizes (2.5 mm and 4.0 mm) were introduced to study the response of sensors to an existing damage. Stress concentrations were plotted across the width and the sensor results were cor- related with the simulated stress concentrations to evaluate the response of sensors with respect to local stress concentrations. It was found that the screen- printed sensors responded to the stress concentrations since the layers were deposited in the vicinity of notches. The gauge factors altered due to the presence of notches indicating sensor sensitivity to the preexisting damage and resultant stress concentrations. Keywords Smart material, nanocomposites, sensors, screen printing, structural health monitoring 1 Department of Aeronautics and Astronautics, Institute of Space technology, Islamabad, Pakistan 2 Department of Materials Science and Engineering, Institute of Space Technology, Islamabad, Pakistan 3 College of Electrical and Mechanical Engineering, National University of Science and Technology, Islamabad, Pakistan 4 Department of Mechanical Engineering, University of Engineering and Technology, Taxila, Pakistan Corresponding author: M Ali Nasir, Department of Mechanical Engineering, University of Engineering and Technology, Taxila, Pakistan. Email: ali.nasir@uettaxila.edu.pk Journal of Thermoplastic Composite Materials 1–18 ª The Author(s) 2018 Article reuse guidelines: sagepub.com/journals-permissions DOI: 10.1177/0892705718805131 journals.sagepub.com/home/jtc