PSI - Issue 72

Anandito Adam Pratama et al. / Procedia Structural Integrity 72 (2025) 370–376

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obtain a GWFI of 960 °C with a specimen not consumed by the glowing wire. The last documentation, Fig. 2(d), obtained from the study conducted by Naik et al. (2013), shows a magnified view of PA66/GF formulation with AlPi and S200 mixture after glow-wire testing at 960 °C. From Fig. 2(d), small-scale intumescence occurs around the wire contact point, which expands into a heavier intumescence, and the glowing wire could penetrate the specimen.

Fig. 2. Documentation of the glow-wire test result on several polymer materials, (a) PP (Subasinghe et al., 2016), (b) EBA30 (Ribeiro et al., 2017), (c) PC (Krämer and Blomqvist, 2007), and (d) PA66 (Naik et al., 2013).

The results shown in Fig. 2 vary based on the composition of each material. All specimens successfully passed the glow-wire test without producing flaming droplets, meeting the required standards. However, each material exhibited small areas of intumescence or localized burning around the point of wire contact, characteristic of glow-wire test results. PA66 developed holes even though it reached a GWFI of 960 °C, whereas PC, EBA30, and PP only showed slight indentation. 5. Conclusions This paper reviews the material forming process used in mixing polymer materials with flame retardant substances, as well as the characteristics of polymer materials in glow-wire testing. Several material-forming processes are employed to fabricate polymer materials incorporating flame-retardant additives. One of them is extrusion with twin screw extruders, two roll mills which are commonly used for rubber polymers, injection molding, pressure molding, and so on. All materials exhibited intumescence around the wire contact point, indicating a characteristic response to