A cooling-assisted bone micro-grinding method that reduces heat and force may make orthopaedic surgery quicker, gentler – and more precise.
Researchers at Qingdao University of Technology have developed a system that is showcased in Frontiers of Mechanical Engineering.
The study explores a new technique called ultrasonic vibration-assisted nanoparticle jet mist cooling (U-NJMC).
This system combines ultrasonic vibration with a fine spray of nanofluid to keep bones cool and lower resistance during cutting.
The nanofluid is prepared using normal saline as the base fluid, SiO2 nanoparticles as an additive, and PEG400 as a dispersant.
Six grinding processes are tested: dry grinding, drip irrigation, ultrasonic vibration (UV), minimum quantity lubrication (MQL), NJMC, and U-NJMC, with consistent process parameters.
Results reveal the anisotropic nature of bone tissue, with the highest grinding force on the cross-section, followed by the side, and the lowest on the surface.
This variation results from differences in bone structure and the manner in which force is applied in various directions.
Applying grinding fluid or ultrasonic vibration (UV) can decrease the grinding force compared to dry grinding.
U-NJMC micro-grinding produces the least grinding force, the lowest friction coefficient, and the lowest specific grinding energy, and offers the best lubrication.
Dry grinding produces the highest temperatures, while U-NJMC has the lowest.
UV and NJMC can reduce temperatures, and U-NJMC combines both advantages, significantly enhancing the convective heat transfer of the cooling medium and lowering grinding temperature.
The grinding force, friction coefficient, specific grinding energy, and temperature are measured and compared across six different operating conditions.
The results demonstrate U-NJMC’s superior ability to lower temperature and force, providing a new technical reference for micro-grinding technology in orthopaedic surgery.
