Fig. 3.

Load-displacement curves for scratch test on cortical bone. (a) Panorama of a scratch in LT direction. (b) Panorama of a scratch in SL direction. (c) Variation of the horizontal force, penetration depth and acoustic emission along the crack length for LT specimen. (d) Variation of the horizontal force, penetration depth and acoustic emission along the crack length for SL specimen. The magnitudes of both the horizontal force and penetration depth increase as the test progresses. In addition, acoustic emissions are observed.