Electrophoretic deposition was used for HA coating on dental implants with different coating thickness. The HA coating thickness was examined in terms of applied voltage and time, and powder concentration in suspension. Nano-size HA and SiO2-CaO-P2O5-B2O3 bioglass powders were synthesized by sol-gel method. Polyvinyl alcohol (3 wt%) as a binder was resolved in ethyl alcohol, then, nano HA powder was dispersed ultrasonically in the mixture for 15 min and pH was adjusted with HNO3 for positive charging on particle. Titanium substrate was held on cathode and counter electrode was platinum. HA with 0.5 % and 0.03 % of powder concentration was deposited electrophoretically at 10~20 V for 1~20 minutes. The thickness of as-deposited HA layer decreased from nearly 80 µm (0.5 %, 20 V, 10 min) to 4~5 µm (0.03%, 10V, 1 min) as powder concentration, applied voltage and time decreased, respectively. The surface of HA coating layer deposited in lower powder concentration showed much more homogeneous and relatively dense morphology, in contrast, the surface in thick suspension became rough or porous and was easily spalled. In a co-deposition of HA and bioglass, co-deposited glass played an important role in increasing bonding strength between coating layer and substrate. It is believed that electrophoretic deposition method can be one of alternatives for relatively thin and easy HA coating.

Hydroxyapatite/silk fibroin (HAp/SF) composite was prepared and applied to the posterolateral spinal fusion model in rats to observe the effect of bone fusion. Method: Calcium chloride, diammonium phosphate, SF, and polyvinyl alcohol were used as raw materials, HAp/SF composites were prepared by chemical precipitation. The microstructure of the composite, crystal phase composition, and chemical structure were analyzed by the scanning electron microscope (SEM) and X-ray diffraction (XRD), and fourier transform infrared spectrometer (FTIR Spectrometer). Through the cultivation of osteoblasts MC3T3-E1 in vitro, the adhesion and proliferation (A&P) of cells on the face of materials were investigated. Thereby, the biocompatibility of the material was characterized. HAp/SF material was applied to the rat posterolateral spinal fusion model. The osteogenesis and spinal fusion were evaluated by the imaging observation, histological observation and manual palpation. The results showed that the rod-shaped HAp with uniform size and high purity was obtained, with a diameter of 20∼40 nm and a length of 200∼500 nm, similar to the apatite crystal in natural bone tissue (BT). In composite materials, a spatial network structure was formed by the interweaving of the SF fibers, and HAp was deposited on the face of the SF or in the middle of its network structure. In the obtained HAp/SF materials, the calcium ions of HAp and the carbonyl groups of SF were used to form thermally stable complexes through strong chemical bonds. Besides, SF was a template for the directional induction of HAp crystal growth, and the growth of HAp crystal along the C axis was regulated by SF. The growth direction was parallel to the long axis of SF fibers, and was consistent with the structure of apatite crystals deposited on the face of collagen fibers in natural BT. The results of cell culture in vitro showed that: after comparison with the control group (CG) with pure Hap, the adhesion ability of cells to HAp/SF material was significantly improved. The proliferation capacity of bone artificial bone (BAM) material and HAp/SF material was also significantly improved. The nuclear and skeletal staining results of MC3T3-E1 cells on the face of three groups of materials (HAp, BAM and HAp/SF) were combined, and the results also indicated that BAM and HAp/SF materials had good ability to promote cell A&P. The results of posterolateral spinal fusion in rats showed that HAp/SF materials group palpated the posterolateral spine for fusion. The formation of new BT on the posterolateral side of the spine was revealed by the Micro-computed tomography (Micro-CT) examination. In conclusion, HAp/SF composite had good osteoblastic compatibility and can achieve good spinal fusion effect.

Aiming at ceramic-lined layered pipes employed under special conditions, layered structure of ceramic-lined pipes is redesigned by adding (TiO2+Al+C+Ni) subsystem with different contents in (CrO3+Al) main system，and the composite pipe with three-layer structure of steel substrate, the intermediate and ceramics is obtained. SEM images and EPMA analyses indicate that the intermediate is made of Cr-Ni-Fe-Al-Ti, in which Ti carbide particles or fine dendrites of Ti enrichment are embedded with graded distribution. Mechanical tests and SEM images show that as (TiO2+Al+C) subsystem and Ni metallic additive is up to 10% and 15% of whole combustion system respectively, compressive strength and compressive shear strength of the pipe simultaneously reach the maximum values.

Based on using combustion synthesis under high gravity to prepare TiC-TiB2 composite, the ceramic armour targets were achieved by the heat-shrunk laternal, cover and back confinements of steel sleeves and plates. Ballistic testing showed that under the impact of long-rod tungsten alloy projectile, the low-carbon-steel sleeve failed to laterally confine the ceramic due to its inadequate residual strength, resulting in poor ballistic performance of the ceramic, whereas the medium-carbon-steel sleeve had a sufficient residual strength to support lateral confinement of the ceramic as the long-rod tungsten alloy projectile makes room in the ceramic for its penetration, the confined ceramic could present its real ballistic performance, and the results of ballistic testing promised lateral confinement and cover confinement of high-strength metal would be beneficial to the improvement in ballistic performance of ceramic armour.

Based on preparing TiC-40mol%TiB2 composite by combustion synthesis under high gravity, the ballistic targets with different-thickness ceramic tiles were achieved by lateral, cover and back confinements of shrink-fit steel. Ballistic testing showed that as the thickness of ceramic tile was smaller than 12 mm, the penetration of the ceramic tile was mainly controlled by the combination of the initial-shock and steady-state penetration, resulting in poor ballistic performance of the ceramic. As the thickness of ceramic tile was larger than 12 mm, the penetration of the ceramic tile was controlled by the combination of steady-state and third-stage (projectile deceleration and erosion acceleration) penetration, resulting in improved ballistic performance of the ceramic.