Hydroxyapatite Dispersed Magnesium-Based Composite Produced from Pulverized Magnesium Alloy Powder and Its Mechanical Properties

Abstract

A magnesium matrix composite made of Mg-1mass％Ca and 10 vol％ hydroxyapatite (HAp) particles was synthesized. The alloy powder was processed by pulverization of the small blocks of the alloy ingot using a high-speed blade grinder. Unreacted composite was successfully produced by extruding the two component powders at a temperature of 538 K. In the extruded composites, the grains of the magnesium matrix were equiaxed and the matrix grain size was 3.9 µm. As for the HAp particles, both thin clustering and severe agglomeration with the size of ~30 µm were observed. The Young＇s modulus, tensile yield strength and tensile strength of the extruded composite were 39 GPa, 101 MPa and 153 MPa, respectively. The damping capacity of the composite was higher than that of extruded magnesium. The composite also showed good forgeability at a temperature of 523 K. However, quite high impurity contents of Fe (0.130 mass％) and Ni (0.010 mass％) were introduced in the magnesium matrix of the composite, probably as a result of contamination that accumulates during the processing (pulverization) of the alloy powder.

Processing and Mechanical Properties of a Tricalcium Phosphate-Dispersed Magnesium-Based Composite

“…The results obtained for Mg/HAp composites are also included in the figure. 19,20) The loss factor of the extruded X0/¢-TCP/10p composite was slightly higher than that of the extruded X0 alloy, but the damping capacity of the composite was lower than that of the Mg/HAp composites. Particle agglomeration is weaker (i.e., particles are more uniformly distributed) in the X0/¢-TCP/10p composite than in the Mg/HAp composites.…”

“…Particle agglomeration is weaker (i.e., particles are more uniformly distributed) in the X0/¢-TCP/10p composite than in the Mg/HAp composites. 19,20) The slight increase in the damping capacity (extruded X0/¢-TCP/10p composite vs. extruded X0 alloy) and Young's Processing and Mechanical Properties of a Tricalcium Phosphate-Dispersed Magnesium-Based Composite modulus of the composite, which is comparable to that of the alloy, is attributed to this weaker agglomeration. The tensile and compressive properties of the extruded X0 alloy and extruded X0/¢-TCP/10p composite are summarized in Table 2.…”

“…5 Dependence of the loss factor on the strain amplitude of the extruded X0/¢-TCP/10p composite and extruded X0 alloy. The data for Mg/HAp composites 19,20) are also included. shown in Fig.…”