The relationship between topography,thermo magnetic and mechanical properties in the as-cast Gd75Ge15Si5Pr5 alloy was studied.Atomic force microscopy investigations accompanied by micrograph analysis confirm dual phas...The relationship between topography,thermo magnetic and mechanical properties in the as-cast Gd75Ge15Si5Pr5 alloy was studied.Atomic force microscopy investigations accompanied by micrograph analysis confirm dual phase nature(observed as dark and bright phase)of the investigated material.The mechanical properties studies performed with respect to the Oliver-Pharr procedure show that the average instrumental hardness,Young’s modulus and elastic deformation energy to total energy ratio equal 905 HV and 596 HV,131 and 91 GPa,40%and 45%for the dark and bright phase,respectively.The Curie point defined as inflection point on the magnetization versus temperature curve M(T)recorded in zero-field cooled mode equals 283 K.From the law of approach to magnetic saturation the temperature dependence of effective anisotropy constant Keff was calculated in ferromagnetic region.It is also stated that the minimum observed on thermomagnetic M(T)characteristic at 100 K is associated with Keff(T)dependence.展开更多
Hypersonic magneto-fluid-dynamic interaction has been successfully performed as a virtual leading-edge strake and a virtual cowl of a rectangular inlet.In a side-by-side experimental and computational study,the magnit...Hypersonic magneto-fluid-dynamic interaction has been successfully performed as a virtual leading-edge strake and a virtual cowl of a rectangular inlet.In a side-by-side experimental and computational study,the magnitude of the induced compression was found to depend on configuration and electrode placement.To better understand the interacting phenomenon the present investigation is focused on a direct current discharge at the leading edge of a cylindrical inlet for which validating experimental data is available.The present computational result is obtained by solving the magneto-fluid-dynamics equations at the low magnetic Reynolds number limit and using a nonequilibrium weakly ionized gas model based on the drift-diffusion theory.The numerical simulation provides a detailed description of the intriguing physics.After validation with experimental measurements,the computed results further quantify the effectiveness of a magneto-fluid-dynamic compression for a hypersonic cylindrical inlet.A minuscule power input to a direct current surface discharge of 8.14 watts per square centimeter of electrode area produces an additional compression of 6.7 percent for a constant cross-section cylindrical inlet.展开更多
文摘The relationship between topography,thermo magnetic and mechanical properties in the as-cast Gd75Ge15Si5Pr5 alloy was studied.Atomic force microscopy investigations accompanied by micrograph analysis confirm dual phase nature(observed as dark and bright phase)of the investigated material.The mechanical properties studies performed with respect to the Oliver-Pharr procedure show that the average instrumental hardness,Young’s modulus and elastic deformation energy to total energy ratio equal 905 HV and 596 HV,131 and 91 GPa,40%and 45%for the dark and bright phase,respectively.The Curie point defined as inflection point on the magnetization versus temperature curve M(T)recorded in zero-field cooled mode equals 283 K.From the law of approach to magnetic saturation the temperature dependence of effective anisotropy constant Keff was calculated in ferromagnetic region.It is also stated that the minimum observed on thermomagnetic M(T)characteristic at 100 K is associated with Keff(T)dependence.
文摘Hypersonic magneto-fluid-dynamic interaction has been successfully performed as a virtual leading-edge strake and a virtual cowl of a rectangular inlet.In a side-by-side experimental and computational study,the magnitude of the induced compression was found to depend on configuration and electrode placement.To better understand the interacting phenomenon the present investigation is focused on a direct current discharge at the leading edge of a cylindrical inlet for which validating experimental data is available.The present computational result is obtained by solving the magneto-fluid-dynamics equations at the low magnetic Reynolds number limit and using a nonequilibrium weakly ionized gas model based on the drift-diffusion theory.The numerical simulation provides a detailed description of the intriguing physics.After validation with experimental measurements,the computed results further quantify the effectiveness of a magneto-fluid-dynamic compression for a hypersonic cylindrical inlet.A minuscule power input to a direct current surface discharge of 8.14 watts per square centimeter of electrode area produces an additional compression of 6.7 percent for a constant cross-section cylindrical inlet.
