In this work, the effect of heat input on the mechanical properties of low-carbon steel was studied using two welding processes: Oxy-Acetylene Welding (OAW) and Shielded Metal Arc Welding (SMAW). Two different edge pr...In this work, the effect of heat input on the mechanical properties of low-carbon steel was studied using two welding processes: Oxy-Acetylene Welding (OAW) and Shielded Metal Arc Welding (SMAW). Two different edge preparations on a specific size, 10-mm thick low-carbon steel, with the following welding parameters: dual welding voltage of 100 V and 220 V, various welding currents at 100, 120, and 150 Amperes and different mild steel electrode gauges of 10 and 12 were investigated. The tensile strength, hardness and impact strength of the welded joint were carried out and it was discovered that the tensile strength and hardness reduce with the increase in heat input into the weld. However, the impact strength of the weldment increases with the increase in heat input. Besides it was also discovered that V-grooved edge preparation has better mechanical properties as compared with straight edge preparation under the same conditions. Microstructural examinations conducted revealed that the cooling rate in different media has significant effect on the microstructure of the weldment. Pearlite and ferrite were observed in the microstructure, but the proportion of ferrite to pearlite varied under different conditions.展开更多
Steels are used widely for production of machine components due to their versatility, low cost, ease of production and modification of their properties through heat-treatment. ST60Mn Steel is one of the common high st...Steels are used widely for production of machine components due to their versatility, low cost, ease of production and modification of their properties through heat-treatment. ST60Mn Steel is one of the common high strength steel produced in Nigeria and utilized for machine building purposes. Components made from this materials failed by wear, corrosion or both mechanism. The aim of this paper is to determine the influence of austempering heat-treatment on the corrosion-wear resistance of ST60Mn steel in cassava juice. The heat-treatment was performed by varying the austenitizing temperature, austempering temperature and time. The corrosion wear resistance was investigated under an instrumented pin-on-disc wear testing machine with the steel samples dipped in the cassava juice. The results obtained showed that the austempered ST60Mn steel has a wear rate of 3.0μg/cycle. While, the un-heat-treatment sample possess 70.1μg/cycle. This is a tremendous improvement in corrosion wear rate through the austempering heat treatment.展开更多
文摘In this work, the effect of heat input on the mechanical properties of low-carbon steel was studied using two welding processes: Oxy-Acetylene Welding (OAW) and Shielded Metal Arc Welding (SMAW). Two different edge preparations on a specific size, 10-mm thick low-carbon steel, with the following welding parameters: dual welding voltage of 100 V and 220 V, various welding currents at 100, 120, and 150 Amperes and different mild steel electrode gauges of 10 and 12 were investigated. The tensile strength, hardness and impact strength of the welded joint were carried out and it was discovered that the tensile strength and hardness reduce with the increase in heat input into the weld. However, the impact strength of the weldment increases with the increase in heat input. Besides it was also discovered that V-grooved edge preparation has better mechanical properties as compared with straight edge preparation under the same conditions. Microstructural examinations conducted revealed that the cooling rate in different media has significant effect on the microstructure of the weldment. Pearlite and ferrite were observed in the microstructure, but the proportion of ferrite to pearlite varied under different conditions.
文摘Steels are used widely for production of machine components due to their versatility, low cost, ease of production and modification of their properties through heat-treatment. ST60Mn Steel is one of the common high strength steel produced in Nigeria and utilized for machine building purposes. Components made from this materials failed by wear, corrosion or both mechanism. The aim of this paper is to determine the influence of austempering heat-treatment on the corrosion-wear resistance of ST60Mn steel in cassava juice. The heat-treatment was performed by varying the austenitizing temperature, austempering temperature and time. The corrosion wear resistance was investigated under an instrumented pin-on-disc wear testing machine with the steel samples dipped in the cassava juice. The results obtained showed that the austempered ST60Mn steel has a wear rate of 3.0μg/cycle. While, the un-heat-treatment sample possess 70.1μg/cycle. This is a tremendous improvement in corrosion wear rate through the austempering heat treatment.
