Ali Ahmad Khan - Academia.edu (original) (raw)
Teaching Documents by Ali Ahmad Khan
Proper heat treatment of steels is one of the most important factors in determining how they will... more Proper heat treatment of steels is one of the most important factors in determining how they will perform in service. Engineering materials, mostly steel, are heat treated under controlled sequence of heating and cooling to alter their physical and mechanical properties to meet desired engineering applications. In this study we have chosen AISI 1020 steel as for our research work and we have tried to find out the mechanical properties (hardness) and micro structural properties by means of appropriate heat treatment process (annealing, normalizing & quenching). Here the steel specimens were heat treated in a furnace at different temperature levels and soaking time; and then cooled in various media (furnace, air, water, oil, and brine). After that the hardness of the specimens were rechecked for the comparison with previous data and the microstructures of the specimens were examined using metallurgical microscope equipped with camera. These results showed that the hardness of AISI 1020 steel can be changed and improved by different heat treatments for a particular application. From the microstructures we have found that the annealed specimens with mainly ferrite structure give the lowest hardness value and highest ductility while quenched specimens give the highest hardness value and lowest ductility. On the other hand, normalized specimens have given the moderate hardness and ductility comparing with hardened and annealed specimens.
The processes to enrich the iron ore has made necessary utilization of concentration processes. A... more The processes to enrich the iron ore has made necessary utilization of concentration processes. A fine granulometry is produced because of these processes since the iron agglomeration process is necessary in blast furnace to obtain required product from iron ore. Some certain agglomeration processes include briquetting, extrusion, nodulization, pelletizing and sintering, especially sintering process is used for 70% blast furnace load and that of sintering is also a widely used technique. Along with the agglomerated product, the main objective is to obtain desirable characteristics like, thermal, mechanical, physical, and chemical properties in a product that is then fed in the blast furnace, achieving a homogenous and stable operation inn this furnace with economical profitability.
Ali Ahmad Khan, 2023
Traditional formaldehyde-based adhesives still play a crucial role in current market, despite inc... more Traditional formaldehyde-based adhesives still play a crucial role in current market, despite increasing environmental concerns resulting from their production. The purpose of this report was to evaluate the environmental impact of Urea-Formaldehyde (UF), mainly used in wood products. This report supports the Life Cycle Assessment (LCA) of urea-formaldehyde. Several key parameters for life cycle analysis were analyzed, such as global warming potential acidification potential, eutrophication potential, and human health. As a result, the greenhouse gas ranged to 2.04 kg CO2-eq./kg adhesive. In terms of overall impacts, it was found that UF had a nearly 50% higher life cycle impact than phenol formaldehyde. Energy consumption of UF was much lower than other adhesives. Transportation distance was determined to be a sensitive parameter with resect to global warming potential for formaldehyde-based adhesive.
Proper heat treatment of steels is one of the most important factors in determining how they will... more Proper heat treatment of steels is one of the most important factors in determining how they will perform in service. Engineering materials, mostly steel, are heat treated under controlled sequence of heating and cooling to alter their physical and mechanical properties to meet desired engineering applications. In this study we have chosen AISI 1020 steel as for our research work and we have tried to find out the mechanical properties (hardness) and micro structural properties by means of appropriate heat treatment process (annealing, normalizing & quenching). Here the steel specimens were heat treated in a furnace at different temperature levels and soaking time; and then cooled in various media (furnace, air, water, oil, and brine). After that the hardness of the specimens were rechecked for the comparison with previous data and the microstructures of the specimens were examined using metallurgical microscope equipped with camera. These results showed that the hardness of AISI 1020 steel can be changed and improved by different heat treatments for a particular application. From the microstructures we have found that the annealed specimens with mainly ferrite structure give the lowest hardness value and highest ductility while quenched specimens give the highest hardness value and lowest ductility. On the other hand, normalized specimens have given the moderate hardness and ductility comparing with hardened and annealed specimens.
The processes to enrich the iron ore has made necessary utilization of concentration processes. A... more The processes to enrich the iron ore has made necessary utilization of concentration processes. A fine granulometry is produced because of these processes since the iron agglomeration process is necessary in blast furnace to obtain required product from iron ore. Some certain agglomeration processes include briquetting, extrusion, nodulization, pelletizing and sintering, especially sintering process is used for 70% blast furnace load and that of sintering is also a widely used technique. Along with the agglomerated product, the main objective is to obtain desirable characteristics like, thermal, mechanical, physical, and chemical properties in a product that is then fed in the blast furnace, achieving a homogenous and stable operation inn this furnace with economical profitability.
Ali Ahmad Khan, 2023
Traditional formaldehyde-based adhesives still play a crucial role in current market, despite inc... more Traditional formaldehyde-based adhesives still play a crucial role in current market, despite increasing environmental concerns resulting from their production. The purpose of this report was to evaluate the environmental impact of Urea-Formaldehyde (UF), mainly used in wood products. This report supports the Life Cycle Assessment (LCA) of urea-formaldehyde. Several key parameters for life cycle analysis were analyzed, such as global warming potential acidification potential, eutrophication potential, and human health. As a result, the greenhouse gas ranged to 2.04 kg CO2-eq./kg adhesive. In terms of overall impacts, it was found that UF had a nearly 50% higher life cycle impact than phenol formaldehyde. Energy consumption of UF was much lower than other adhesives. Transportation distance was determined to be a sensitive parameter with resect to global warming potential for formaldehyde-based adhesive.