Mechanical Properties and Machining Behavior of AZ31-Calcium Deficient Hydroxyapatite (CDHA) Biodegradable Composites

Abstract

In order to create biodegradable magnesium-based implants, calcium-deficient hydroxyapatite (CDHA) nanoparticles were incorporated into AZ31 magnesium (Mg) alloy using friction stir processing. When compared to the AZ31 base alloy (41.4±5.9 µm), the composites showed grain refinement up to 1.8±1.9 µm. The composition of the produced composites is confirmed by characterization using electron microscopy and X-ray diffraction analysis. Because of the reduced grain size and the added nano-CDHA, the composite’s hardness (91±12.6 HV0.1) was higher than the parent alloy’s (46±3.3 HV0.1). Both the base alloy and the composite have undergone uni-axial tensile testing. In comparison to the basic alloy (225±4.9 MPa), the grain refined composite has demonstrated a comparatively higher strength (283.6±5.1 MPa). Machining studies carried out by drilling experiments at 90 rpm and 180 rpm with 15 mm/min and 30 mm/min feed revealed higher cutting forces for the composites. However, the edge damage in the produced holes was observed as significantly lower for the composites compared with the base alloy.