Predavanje prof. dr. sc. Abhijit Majumdar "Protective Textiles: Materials and Technology, 1. Soft body armour and 2. UV protection by textiles" 14.7.2021.
U okviru projekta Internacionalizacija doktorskog studija Tekstilna znanost i tehnologija prof. dr. sc. Abhijit Majumdar sa Indian Institute of Technology, Department of Textile and Fibre Engineering, New Delhi, Indija, održati će predavanje pod naslovom Protective Textiles: Materials and Technology, 1. Soft body armour and 2. UV protection by textiles. Predavanje će se održati u srijedu, 14.7.2021., u 10:00 sati preko MS Teams platforme.
Body armours are primarily classified under two heads, namely soft and hard. While the former is used when the threat level is low, the latter is apt to ensure protection when the threat level is very high. In recent years, there has been immense developments in materials and designs of body armour. However, to ensure effective protection, at least 15-20 layers of fabrics are required. Soft body armor technology revolves around fabrics prepared from high performance polymeric fibres such as p-aramid (Kevlar®, Technora®, Twaron® etc.), ultra-high molecular weight polyethylene (UHMWPE), poly p-phenylene benzobisoxazole or PBO fibre (Zylon), polyhydroquinone-diimidazopyridine or PIPD fibres (M5), etc. The essential properties of the above fibres are low density (0.97 to 1.6 g cm-3), high tenacity (2.5–5.8 GPa) and high modulus (70-270 GPa). Of late, UHMWPE yarns have gained predominance over aramid yarns owing to their higher strength to weight ratio.
Another fascinating area of research in this domain is the application of Shear thickening fluid (STF) to improve the ballistic performance of bullet resistant and stab resistant soft armor. STF is a dense colloidal dispersion having a solid dispersed phase (silica particles) in a liquid dispersion medium (PEG). This fluid exhibits non-Newtonian flow behavior. Beyond a critical shear rate, the viscosity rises abruptly and the liquid behaves like a solid. It has been found that the STF treated soft body armour panels, evaluated against low velocity projectiles, shows the improvement in the impact performance.
There are many standards available to evaluate the body armour and the one from National Institute of Justice (NIJ), USA, is the most popular. The value of permissible back face deformation is different according to different standards and therefore, it requires unique materials and their stacking sequence to fulfil the requirement. Mitigating the back face while minimizing the areal density of armour panel presents a great challenge to the textile scientists working in this domain.CV
ABHIJIT MAJUMDAR is the professor and Institute Chair of Department of Textile and Fibre Engineering at the Indian Institute of Technology, New Delhi. His areas of interests are textile engineering (yarn and fabric manufacturing), protective textiles (ballistics and UV protection), operations management, sustainable supply chain management, soft computing and multi-criteria decision making.
- 05.07.2021 08:24