The present study deals with the investigation of dry sliding wear behavior of aluminium alloy based composites, reinforced with silicon carbide particles and solid lubricants such as graphite/antimony tri sulphide (S...The present study deals with the investigation of dry sliding wear behavior of aluminium alloy based composites, reinforced with silicon carbide particles and solid lubricants such as graphite/antimony tri sulphide (Sb2S3). The first one of the composites (binary) consists of Al. with 20% Silicon Carbide particles (SiCp) only. The other composite has SiCp and solid lubricants: Graphite + Sb2S3 (hybrid composite) at solid state. Both composites are fabricated through P/M route using “Hot powder perform forging technology”. The density and hardness are measured by usual methods. The pin-on-disc dry wear tests to measure the tribological properties are conducted for one hour at different parameters namely load: 30, 50 and 80N and speed: 5, 7 and 9m/s. The tested samples are examined using scanning electron microscope (SEM) for the characterization of microstructure and tribolayer on worn surface of composites. The results reveal that wear rate of hybrid composite is lower than that of binary composite. The wear rate decreased with the increasing load and increased with increasing speed. The results of the proposed composites are compared with iron based metal matrix composites (FM01N, FM02) at corresponding values of test parameters. These iron based metal matrix composites are also fabricated by P/M route using ‘Hot powder perform forging technology’. The comparative study reveals that the proposed composites have lower friction coefficient, less temperature rise and low noise level;however they have little higher wear rate. It is concluded that the hybrid composite has acceptable level of tribological characteristics with blacky and smooth worn surface.展开更多
The aims of the present study is to develop a powder based steel used as backing plate for heavy duty brake pad applications. Three powder based back plate steel compositions namely B1 (C- 0.3, Cu – 1.5, P -0.3, Fe ...The aims of the present study is to develop a powder based steel used as backing plate for heavy duty brake pad applications. Three powder based back plate steel compositions namely B1 (C- 0.3, Cu – 1.5, P -0.3, Fe – 97.9), B2 (C- 0.1, Cu – 2.5, SiC-1, Fe – 96.4) and B3(C- 0.5, Cu – 2.5, SiC-1, Fe – 96.0) were prepared using a hot powder preform forging technique. The forged samples are of (25× 50×10 mm3) dimensions. These samples were hot rolled and annealed to relieve the residual stresses. These samples were characterized in terms of microstructure, porosity content/densification, hardness and tensile properties. Densification as high near to theoretical density has been realized. Hot powder preform forging using closed die showed better densification. Rolled and annealed microstructure showed lesser porosity content than the forged one. Phosphorous causes hardening of ferrite in solid solution with iron. Compositions B1, showed reasonable elongation and it improved further on annealing. It was observed in this present investigation that, the addition, such as SiC and Cu caused increase in strength. Steel developed in the investigation are used as powder based backing plate in Manufacturing of iron based brake pads used in heavy duty applications.展开更多
The relation between normalized thermal en-ergy and conductivity, with no particle sources in cylindrical tokamak geometry has been de-rived. It is obtained, . This relationship is of importance for tokamak confinemen...The relation between normalized thermal en-ergy and conductivity, with no particle sources in cylindrical tokamak geometry has been de-rived. It is obtained, . This relationship is of importance for tokamak confinement and heating.展开更多
A set of reduced MHD equations is derived us-ing the standard energy balance equation. By applying assumption of internal energy, i.e. , a set of reduced magnetohydro-dynamic equations are obtained for large aspect ra...A set of reduced MHD equations is derived us-ing the standard energy balance equation. By applying assumption of internal energy, i.e. , a set of reduced magnetohydro-dynamic equations are obtained for large aspect ratio, high tokamaks. These equations in-clude all terms of the same or der as the toroidal effect and only involve three variables, namely the ?ux, stream function and internal energy.展开更多
Calculation of Plasma internal inductance (li) is essential in Tokamak plasma research. Much more plasma parameters such as the plasma current density profile, magnetohydrodynamics instability, and plasma energy confi...Calculation of Plasma internal inductance (li) is essential in Tokamak plasma research. Much more plasma parameters such as the plasma current density profile, magnetohydrodynamics instability, and plasma energy confinement time can be determined by using this parameter. Discrete poloidal magnetic probes along with the diamagnetic loop can be utilized in measurement of the Plasma internal inductance (li). In this paper Plasma internal inductance (li) is studied by theoretical and experimental approach for HT-7 Tokamak plasmas. The results of two methods are in good agreement with each other.展开更多
In this work, we present effective edge safety factor using analytical solution of the Grad-Shafranov equation based on expansion of free functions of first order and magnetic probes for circular cross section HT-7 to...In this work, we present effective edge safety factor using analytical solution of the Grad-Shafranov equation based on expansion of free functions of first order and magnetic probes for circular cross section HT-7 tokamak.展开更多
文摘The present study deals with the investigation of dry sliding wear behavior of aluminium alloy based composites, reinforced with silicon carbide particles and solid lubricants such as graphite/antimony tri sulphide (Sb2S3). The first one of the composites (binary) consists of Al. with 20% Silicon Carbide particles (SiCp) only. The other composite has SiCp and solid lubricants: Graphite + Sb2S3 (hybrid composite) at solid state. Both composites are fabricated through P/M route using “Hot powder perform forging technology”. The density and hardness are measured by usual methods. The pin-on-disc dry wear tests to measure the tribological properties are conducted for one hour at different parameters namely load: 30, 50 and 80N and speed: 5, 7 and 9m/s. The tested samples are examined using scanning electron microscope (SEM) for the characterization of microstructure and tribolayer on worn surface of composites. The results reveal that wear rate of hybrid composite is lower than that of binary composite. The wear rate decreased with the increasing load and increased with increasing speed. The results of the proposed composites are compared with iron based metal matrix composites (FM01N, FM02) at corresponding values of test parameters. These iron based metal matrix composites are also fabricated by P/M route using ‘Hot powder perform forging technology’. The comparative study reveals that the proposed composites have lower friction coefficient, less temperature rise and low noise level;however they have little higher wear rate. It is concluded that the hybrid composite has acceptable level of tribological characteristics with blacky and smooth worn surface.
文摘The aims of the present study is to develop a powder based steel used as backing plate for heavy duty brake pad applications. Three powder based back plate steel compositions namely B1 (C- 0.3, Cu – 1.5, P -0.3, Fe – 97.9), B2 (C- 0.1, Cu – 2.5, SiC-1, Fe – 96.4) and B3(C- 0.5, Cu – 2.5, SiC-1, Fe – 96.0) were prepared using a hot powder preform forging technique. The forged samples are of (25× 50×10 mm3) dimensions. These samples were hot rolled and annealed to relieve the residual stresses. These samples were characterized in terms of microstructure, porosity content/densification, hardness and tensile properties. Densification as high near to theoretical density has been realized. Hot powder preform forging using closed die showed better densification. Rolled and annealed microstructure showed lesser porosity content than the forged one. Phosphorous causes hardening of ferrite in solid solution with iron. Compositions B1, showed reasonable elongation and it improved further on annealing. It was observed in this present investigation that, the addition, such as SiC and Cu caused increase in strength. Steel developed in the investigation are used as powder based backing plate in Manufacturing of iron based brake pads used in heavy duty applications.
文摘The relation between normalized thermal en-ergy and conductivity, with no particle sources in cylindrical tokamak geometry has been de-rived. It is obtained, . This relationship is of importance for tokamak confinement and heating.
文摘A set of reduced MHD equations is derived us-ing the standard energy balance equation. By applying assumption of internal energy, i.e. , a set of reduced magnetohydro-dynamic equations are obtained for large aspect ratio, high tokamaks. These equations in-clude all terms of the same or der as the toroidal effect and only involve three variables, namely the ?ux, stream function and internal energy.
文摘Calculation of Plasma internal inductance (li) is essential in Tokamak plasma research. Much more plasma parameters such as the plasma current density profile, magnetohydrodynamics instability, and plasma energy confinement time can be determined by using this parameter. Discrete poloidal magnetic probes along with the diamagnetic loop can be utilized in measurement of the Plasma internal inductance (li). In this paper Plasma internal inductance (li) is studied by theoretical and experimental approach for HT-7 Tokamak plasmas. The results of two methods are in good agreement with each other.
文摘In this work, we present effective edge safety factor using analytical solution of the Grad-Shafranov equation based on expansion of free functions of first order and magnetic probes for circular cross section HT-7 tokamak.
