Impact evaluation in carbon fiber reinforced plastic (CFRP) laminates using eddy current pulsed thermography

Yunze He,Guiyun Tian,Mengchun Pan,Dixiang Chen

doi:10.1016/j.compstruct.2013.10.049

Abstract

With the growing interest to use engineering composite structures, much attention is devoted to the development of non-destructive testing (NDT) techniques for impact evaluation. Eddy current pulsed thermography (ECPT) is an emerging NDT technique, which is firstly investigated for crack evaluation in carbon fiber reinforced plastic (CFRP) in 2011 and the preliminary results have shown the significant potential. However, the research is limited by the experimental conditions. In this work, the detection mechanism for carbon fiber structure and impact are analyzed through theoretic analysis and validated by experimental studies under reflection and transmission modes. Laminates impacted with different energies from 4J to 12J are characterised. The qualitative and quantitative conclusions for impact behavior understanding are outlined, which is helpful to develop the reliable instruments for quality control and in-service inspection of CFRP.

Highlights

In recent decades, there has been an increasing interest in the use of carbon fiber reinforced plastic (CFRP), in the aerospace, renewable energy and other industries, due to low weight and relatively good mechanical properties compared with traditional metals
The impact laminates are tested using eddy current pulsed thermography under reflection mode shown in Fig. 6a and transmission mode shown in Fig. 6b, respectively
An emerging non-destructive testing (NDT) technique, eddy current pulsed thermography is investigated for CFRP testing and impact evaluation

Summary

Introduction

There has been an increasing interest in the use of carbon fiber reinforced plastic (CFRP), in the aerospace, renewable energy and other industries, due to low weight and relatively good mechanical properties compared with traditional metals. Impact events are inevitable during the lifetime of a composite structure, occurring during both service and maintenance in the form of collisions with stones or tools. Such events can cause extensive internal delamination. This damage, while often difficult or even impossible to detect at the surface of the material, severely degrades the loadbearing capacity of the structure [1]. To achieve these problems, NDT techniques based on acoustic, like ultrasonic testing [2], acoustic emission [3,4] are widely used.

Methods

Results

Conclusion