Coating needles with metallic glass to overcome fracture toughness and trauma: Analysis on porcine tissue and polyurethane rubber

Abstract

In this study, we assessed the characteristics of thin film metallic glass (TFMG)-coated needles by inserting them into polyurethane rubber blocks and porcine skin with underlying fat and muscle. The insertion of TFMG-coated needles was shown to reduce the fracture toughness of the porcine tissue and polyurethane rubber by ~24%, compared to the bare needles. In the pierce-through experiments performed on 3.3 mm-thick test samples, the coated needles required ~27% less time to reach the peak force when applied to rubber samples and ~14% less time when applied to porcine tissue. The reason for the low resistance to fracturing was elucidated by using an optical microscope to examine the area of the hole created by the first insertion of the needle. The area of the hole created by the TFMG-coated needle was ~44% smaller than that created by the bare needle, indicating less damage to the testing materials. Overall, the TFMG-coated needles were associated with lower cutting forces, frictional forces, and resistance to insertion.