Tianjin International Conference on Biomaterials，Bio-Design and Manufacturing (BDMC2019)

51 / 2019-07-14 10:16:44

Mechanism of material removal in orthogonal cutting of cortical bone

bone cutting,chip formation,crack propagation,surface damage

Plenary track > Novel bio-manufacturing systems and technologies

Bone cutting is an important fundamental bone removal process in surgical operation. Studying the cutting mechanism has important theoretical and practical significance to investigate clinical orthopaedic surgeries and develop new bone-cutting technologies as well as innovative orthopaedic instruments. In this study, the chip formation mechanism in orthogonal cutting with cortical bone was investigated. Chip morphology and crack propagation of cortical bone under various cutting directions and depths-of-cut (DOCs) were analysed with consideration of microstructural and sub-microstructural characteristics of cortical bone as well as material anisotropy caused by distribution directions of osteons. Decisive effects of different material properties with osteon, interstitial matrix and cement line on chip morphology and crack propagation along different cutting directions were interpreted. The essence was revealed that chip morphology difference in various DOCs was due to the comparable size correlation of osteon, lamella and DOC. In addition, the SEM images of surface and side of machined bone material showed that the surface damaged most seriously in transverse direction cutting. This study reveals the chip formation mechanism of orthogonal cutting of cortical bone, which will supply valuable information for investigating on machining damages of bone tissue, processing optimization and clinical applications of orthopaedics instruments.