Byeong-Mo Kang, Hyun-Kuk Park, Jun-Ho Jang, Woon-Jo Jeong, Kyung-Ku Lee, Ik-Hyun Oh, Hoon-Sung Cho, Ho-Geun Ahn, and Yeong-Seog Lim
Using the spark plasma sintering (SPS) method, hydroxyapatite (HAp) material was densified using a hydroxyapatite powder (RND Korea, 45 ã??, purity 98 +%). The HAp was nearly completely dense with a relative density of up to 97 % after the simultaneous application of 60 MPa of pressure and about 30 minutes of electric current without significant change in the grain size. The average grain size of HAp that was produced through SPS was approximately 13.2 ã??. The hardness and fracture toughness of the HAp sintered-body at 1200 °C were 253 ± 0.5 kg/mm2 and 0.48 ± 0.02 MPam1/2.