Figure 5.

(a) Compressive elastic modulus, ultimate and yield strength determined for PEEK and PEEK/HA specimens compressed in different directions; (b) sequential images of PEEK/HA biocomposites at size 6 × 6 × 6 mm³ with 40 Vol% HA during compression in different directions; and (c–g) optical images of the samples after compression test: (c) top view of unfilled PEEK sample; (d) top view of PEEK/HA compressed in direction 1; (e) top view of PEEK/HA compressed in direction 2; and (f,g) front and side view of PEEK/HA compressed in direction 2. The yellow arrows in the image (f) show the plastic flow under pressure.