• 제목/요약/키워드: porcine knee joint cartilage

검색결과 2건 처리시간 0.015초

반복 회전운동에서 코발트 크롬 합금과 미끄럼 접촉하는 돼지 무릎 관절연골의 접촉압력이 마찰계수 변화에 미치는 영향 (Effect of Contact Pressure on the Variations in Coefficients of Friction Between Porcine Knee Joint Cartilage and Co-Cr Alloy in a Repeat Pass Sliding Motion)

  • 이권용;김환;이영제
    • Tribology and Lubricants
    • /
    • 제25권4호
    • /
    • pp.231-235
    • /
    • 2009
  • In this study, the influence of contact pressure on the variation in coefficients of friction between porcine knee joint cartilage and Co-Cr alloy in a repeat pass sliding motion was investigated. Flat-ended cartilage pin specimens(9 mm diameter, 8 mm long) were prepared from porcine(6 months old) knee joints by a drill-type punch. Friction tests were conducted by using a pin-on-disk type friction tester for an hour in PBS lubricated condition under the contact pressures of 0.5, 1 and 2 MPa with 50 mm distance per a cycle at ambient condition. As a result, coefficients of friction increased as the test duration increased for all contact pressures. The maximum coefficients of friction were 0.082, 0.06 and 0.098 for 0.5, 1, and 2 MPa, respectively. It showed that coefficients of friction of porcine knee joint cartilage against Co-Cr alloy depended on the level of contact pressure and related to squeeze film lubrication mechanism.

기구학적 운동이 돼지 무릎 관절연골의 마찰계수 변화에 미치는 영향 (Effect of Kinematic Motion on Changes in Coefficients of Friction of Porcine Knee Joint Cartilage)

  • 김환;김충연;이권용;김대준;임도형
    • Tribology and Lubricants
    • /
    • 제29권1호
    • /
    • pp.46-50
    • /
    • 2013
  • In this study, the frictional behaviors of articular cartilage against a Co-Cr alloy in two types of kinematic motions were compared. Cartilage pins were punched from the femoral condyles of porcine knee joints, and Co-Cr alloy disks were machined from orthopedic-grade rods and polished to a surface roughness ($R_a$) of 0.002. Friction tests were conducted by using a pin-on-disk-type tribotester in phosphate buffered saline (PBS) under pressures of 0.5, 1, and 2 MPa. All tests were performed in the repeat pass rotational (ROT) and the linear reciprocal (RCP) sliding motions with the same sliding distance and speed of 50 mm/s. The coefficients of friction of the cartilage against the Co-Cr alloy increased with the sliding time in both kinematic motions for all contact pressures. The maximum coefficients of friction in RCP motion were 1.08, 2.82, and 1.96 times those in ROT motion for contact pressures of 0.5, 1, and 2 MPa, respectively. As the contact pressure increased, the coefficients of friction gradually increased in RCP motion, whereas they decrease and then increased in ROT motion. The interaction between the directional change of the shear stress and the orientation of collagen fiber in the superficial layer of the cartilage could affect the change in the frictional behaviors of the cartilage. A large difference in the coefficients of friction between the two kinematic motions could be interpreted as differences in the directional change of shear stress at the contact surface.