Hydroxyapatites Produced by Wet‐Chemical Methods

Hydroxyapatite samples were produced by two different wet‐chemical methods, and characterized by X‐ray diffraction, infrared (IR), thermal gravimetric analysis (TGA), scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, inductively coupled plasma atomic emission spectrometry, and compression strength measurements. The IR spectra showed the presence of CO ₃ ²⁻ ions in all samples. After the sintering, the CO ₃ ²⁻ bands almost disappeared, indicating a large release of CO ₃ ²⁻ ions by the samples, which were also confirmed by TGA. By mixing samples produced by both methods, a bioceramic was prepared and, after sintering at 900°C for 1 h, compressive strengths of 26–30 MPa were obtained.