NT Reporter
Panaji
A composite material developed using cashew nut shell liquid (CNSL), extracted from cashew-processing waste, and natural bamboo fibre has shown promising potential in lightweight ballistic protection, with the material successfully arresting projectiles during experimental trials.
Gaurish Samant, who recently completed his PhD in Mechanical Engineering from Goa University under the guidance of Prof Dr Rajesh Suresh Prabhu Gaonkar, developed the natural fibre composite as part of his doctoral research titled ‘Development, Characterisation and Statistical Analysis of Natural Fibre Reinforced Cashew Nut Shell Liquid
Matrix Composite.’
“My research focuses on developing a lightweight natural fibre composite using cashew nut shell liquid, extracted from cashew nut shells, and natural bamboo fibre. The CNSL acts as the matrix material, while bamboo fibre provides reinforcement,” Samant said.
The composite panels underwent mechanical characterisation and ballistic testing using two experimental approaches. Trials conducted using an INSAS rifle reportedly saw the composite successfully arrest the bullet. Further ballistic impact testing was carried out at the National Institute of Technology Karnataka (NITK), Surathkal, using its gas gun bullet testing facility.
“The composite specimens were tested using a 5.54 mm projectile at velocities of up to 1,174 m/s. The developed composite successfully arrested the projectile during the reported experiments,” Samant said.
He said the results demonstrated the material’s potential for protective applications. However, formal evaluation and certification are still being pursued, with further testing planned at the National Forensic Sciences University and a DRDO laboratory in Chandigarh.
A key advantage being explored is the material’s weight and estimated cost. According to approximate figures provided by Samant, a conventional steel plate weighing 4 kg costs around Rs 7,000, while synthetic fibre with a ceramic plate of similar weight costs between Rs 40,000 and Rs 50,000. The developed CNSL-bamboo composite panel, meanwhile, weighs approximately 0.5 kg and is estimated to cost around Rs 3,000.
“One of the promising features of the developed composite is its potential to significantly reduce the weight and cost of protective panels,” he said.
However, Samant said further validation, repeatability studies, durability testing, optimisation and larger-scale fabrication would be necessary before the material could be considered for practical defence deployment.
He said the research also explores the utilisation of cashew-processing by-products and locally available natural resources to develop value-added engineering materials.
“By combining CNSL with bamboo fibre, the research explores how locally available resources can be transformed into advanced composite materials,” he said, adding that the work seeks to connect local resource utilisation with advanced engineering applications and contribute to Swayampurna Goa through research-led sustainable development.
