In order to obtain an effective and reliable grain refiner for Mg-Al alloys, 1% (mass fraction) Mg3N2 was added into AZ31 Mg alloy. The microstructures of the Mg alloys were studied by optical microscopy, scan elect...In order to obtain an effective and reliable grain refiner for Mg-Al alloys, 1% (mass fraction) Mg3N2 was added into AZ31 Mg alloy. The microstructures of the Mg alloys were studied by optical microscopy, scan electron microscopy and X-ray energy dispersive spectroscopy, and the mechanical properties were determined. The results show that adding a small amount of Mg3N2 to AZ31 Mg alloy can refine the grain size from 103 to 58 μm. The ultimate tensile strength and elongation of AZ31 Mg alloy are 174.1MPa and 8.3%, respectively. After the addition of 1% Mg3N2, the ultimate tensile strength and elongation of AZ31 Mg alloy are increased up to 198.7 MPa and 11.8%, respectively. The grain refinement mechanism is that AIN is formed after Mg3N2 is added. Both AIN and Mg phases are of HCP lattice structure, and the disregistry between Mg phases and AIN along (0001)Mg//(0001)AIN is 3.04%, which is very effective for heterogeneous nucleation.展开更多
Mg(OH)2 powders were formed by the decomposition of Mg3N2 powders synthesized by a simple reaction of Mg with N Ha. X-ray diffraction(XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron m...Mg(OH)2 powders were formed by the decomposition of Mg3N2 powders synthesized by a simple reaction of Mg with N Ha. X-ray diffraction(XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy(SEM) were used to study the structure, composition and morphology of the products. Mg (OH)2 nanowires with an average diameter about 300 nm-500 nm were found in these Mg(OH)2 powders.展开更多
基金Project(2007430023)supported by the Office of Education,Henan Province,ChinaProject(0612002500)supported by the Excellent Young Scientists Foundation of Henan Province,China
文摘In order to obtain an effective and reliable grain refiner for Mg-Al alloys, 1% (mass fraction) Mg3N2 was added into AZ31 Mg alloy. The microstructures of the Mg alloys were studied by optical microscopy, scan electron microscopy and X-ray energy dispersive spectroscopy, and the mechanical properties were determined. The results show that adding a small amount of Mg3N2 to AZ31 Mg alloy can refine the grain size from 103 to 58 μm. The ultimate tensile strength and elongation of AZ31 Mg alloy are 174.1MPa and 8.3%, respectively. After the addition of 1% Mg3N2, the ultimate tensile strength and elongation of AZ31 Mg alloy are increased up to 198.7 MPa and 11.8%, respectively. The grain refinement mechanism is that AIN is formed after Mg3N2 is added. Both AIN and Mg phases are of HCP lattice structure, and the disregistry between Mg phases and AIN along (0001)Mg//(0001)AIN is 3.04%, which is very effective for heterogeneous nucleation.
文摘Mg(OH)2 powders were formed by the decomposition of Mg3N2 powders synthesized by a simple reaction of Mg with N Ha. X-ray diffraction(XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy(SEM) were used to study the structure, composition and morphology of the products. Mg (OH)2 nanowires with an average diameter about 300 nm-500 nm were found in these Mg(OH)2 powders.