The utilization of carburizing materials in surface engineering has undergone many tremendous changes. Effective quality control is possible through carburizing the steel components under op-timal conditions. In this ...The utilization of carburizing materials in surface engineering has undergone many tremendous changes. Effective quality control is possible through carburizing the steel components under op-timal conditions. In this research work, process parameters like furnace temperature, soaking time and particle size of energizer were taken for optimization of carburized UNS-G10170 steel to yield maximum hardness using Taguchi’s design of experiment concepts and Response Surface Model. Nine experimental runs based on Taguchi’s L9 orthogonal array were performed;signal to noise (S/N) ratios, analysis of variance (ANOVA) and regression analysis were used with hardness as response variable. From the optimization and experimental analyses conducted, it was observed that furnace temperature, soaking time and particle size had significant influence in obtaining a better surface integrity. The optimal values obtained during the study optimization by Taguchi approach and Response Surface Model (RSM) were validated by confirmation experiments.展开更多
This paper studies the antimicrobial activity of selected engineering materials surfaces at room and chill temperatures. The antimicrobial effects of selected materials surfaces were evaluated by dropping the test pie...This paper studies the antimicrobial activity of selected engineering materials surfaces at room and chill temperatures. The antimicrobial effects of selected materials surfaces were evaluated by dropping the test pieces into prepared cultures of Bacillus spp, Escherichia coli, and Staphylococcus aereus isolated from fruits, animal feaces and natural environment respectively. Bacteria count obtained after 0, 30, 60, 90, 120, 180, 240 and 300 minutes at room temperature and chill condition was taken and compared with their initial count. The amount of live bacteria drops by several orders of magnitude, to zero, on metallic copper and brass within 30 to 300 minutes in both room and chill conditions. In contrast, no reduction is seen in the number of colonies of live bacteria on plastics, ceramic and stainless steel in both room and chill conditions. These results suggest that the selection of metallic copper and brass for touch surfaces in hospitals, surfaces exposed to fruit processing and household utensils can materially assist in reducing bacterial contamination, which should lead to a reduction in the transmission of infectious organisms.展开更多
文摘The utilization of carburizing materials in surface engineering has undergone many tremendous changes. Effective quality control is possible through carburizing the steel components under op-timal conditions. In this research work, process parameters like furnace temperature, soaking time and particle size of energizer were taken for optimization of carburized UNS-G10170 steel to yield maximum hardness using Taguchi’s design of experiment concepts and Response Surface Model. Nine experimental runs based on Taguchi’s L9 orthogonal array were performed;signal to noise (S/N) ratios, analysis of variance (ANOVA) and regression analysis were used with hardness as response variable. From the optimization and experimental analyses conducted, it was observed that furnace temperature, soaking time and particle size had significant influence in obtaining a better surface integrity. The optimal values obtained during the study optimization by Taguchi approach and Response Surface Model (RSM) were validated by confirmation experiments.
文摘This paper studies the antimicrobial activity of selected engineering materials surfaces at room and chill temperatures. The antimicrobial effects of selected materials surfaces were evaluated by dropping the test pieces into prepared cultures of Bacillus spp, Escherichia coli, and Staphylococcus aereus isolated from fruits, animal feaces and natural environment respectively. Bacteria count obtained after 0, 30, 60, 90, 120, 180, 240 and 300 minutes at room temperature and chill condition was taken and compared with their initial count. The amount of live bacteria drops by several orders of magnitude, to zero, on metallic copper and brass within 30 to 300 minutes in both room and chill conditions. In contrast, no reduction is seen in the number of colonies of live bacteria on plastics, ceramic and stainless steel in both room and chill conditions. These results suggest that the selection of metallic copper and brass for touch surfaces in hospitals, surfaces exposed to fruit processing and household utensils can materially assist in reducing bacterial contamination, which should lead to a reduction in the transmission of infectious organisms.
