Open AccessInsects use lubricants to minimize friction and wear in leg joints
Author(s) -
Konstantin Nadein,
Alexander Kovalev,
Jan Thøgersen,
Tobias Weidner,
Stanislav N. Gorb
Publication year - 2021
Publication title -
proceedings - royal society. biological sciences/proceedings - royal society. biological sciences
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.342
H-Index - 253
eISSN - 1471-2954
pISSN - 0962-8452
DOI - 10.1098/rspb.2021.1065
Subject(s) - lubricant , joint (building) , composite material , friction coefficient , materials science , polytetrafluoroethylene , coefficient of friction , structural engineering , engineering
A protein-based lubricating substance is discovered in the femoro-tibial joint of the darkling beetle Zophobas morio (Insecta). The substance extrudes to the contacting areas within the joint and appears in a form of filiform flows and short cylindrical fragments. The extruded lubricating substance effectively reduces the coefficient of sliding friction to the value of 0.13 in the tribosystem glass/lubricant/glass . This value is significantly lower than 0.35 in the control tribosystem glass/glass and comparable to the value of 0.14 for the tribosystem glass/dry PTFE (polytetrafluoroethylene or Teflon). The study shows for the first time that the friction-reducing mechanism found in Z. morio femoro-tibial joints is based on the lubricant spreading over the contacting surfaces rolling or moving at low loads and deforming at higher loads, preventing direct contact of joint counterparts. Besides Z. morio , the lubricant has been found in the leg joints of the Argentinian wood roach Blaptica dubia .