Metallurgists have long considered the hardenability evaluation because of its necessity in formulating the hardness penetration rate of alloys with reference to their cooling curves. In this work, we designed and fabricated a Jominy end-quench testing machine by following ASTM-A255, Standard Test Methods for Determining Hardenability of Steel, through computer-aided designing. Our design possesses the novelty of water recycling, cooling tower, water-level indicator, and facile interface, and it is compatible with the environment. A hardenability evaluation test of AISI-8620 case-hardening steel has been performed on the as-fabricated machine. The results confirmed that AISI-8620 achieved the maximum hardness of 43.6 HRC at its quenching end through water quenching. Metallographic studies reveal the formation of a sufficient amount of martensite and other microstructures such as retained austenite, bainite, sorbite, and pearlite.
Environmental pollution particularly from heavy metals in effluent is the gravest problem in developing countries like Pakistan. Effluents of Herbal Pharmaceutical are waste water generated during Herbal Medicines manufacturing process. When these effluents deprived of appropriate treatment are released directly into the environment, results in potential adverse effects on human health and the environment. This research work examined the heavy metals parameters of effluents discharged by Herbal pharmaceutical industry in Karachi, Pakistan. In all, 08 parameters were studied. These include Cr, Mn, Fe, Co, Ni, Cu, Ag and Pb. The study revealed that ranges of Ag and Fe were exceeding the allowable limit of WHO (World Health Organization) and NEQS (National Environmental Quality Standards). This calls for an immediate use of latest treatment plants to decrease the harmfulness that results from waste water.
Freshwater consumption has been increased because of population growth and economic development. At the same time, depletion and contamination of groundwater is subject of great concern. Karachi is the industrial hub and serves as the economic backbone of Pakistan. The research aims to investigate the heavy metal pollution in the groundwater of Korangi Industrial Area, one of the largest industrial estates in Karachi. Eighteen representative locations were selected to collect groundwater samples and study the concentrations of heavy metals Cr, Fe, Ni, Cu, Zn, and Pb. Pollution load index, Nemerow's pollution index, and geo accumulation index approaches were used to interpret the basic data. The average concentrations of the measured heavy metals were 354.67 µg.L-1 , 694.33 µg.L-1 , 39.2 µg.L-1 , 12.89 µg.L-1 , 9.5 µg.L-1 , and 6.17 µg.L-1 for Fe, Zn, Cu, Pb, Cr, and Ni, respectively. The results showed that groundwater quality in the study area is poor and mainly contaminated by Pb and Fe.
Hot rolling and heat treatment are the two industrial metallurgical applications used with compatible steels to modify mechanical properties. In this article, we studied the combined effect of hot rolling and heat treatment at constant parameters on medium carbon steels with respect to reduced thickness. For this purpose, the precasted round billets (110-mm diameter) of AISI-1045 and the square billet (110 by 110 mm) of JIS-SUP 9 were hot rolled and the thickness was reduced up to 6, 8, and 12 mm and 18, 28, and 45 mm, respectively. The hot rolled billets were subjected to heat treatment. The chemical compositions of the steels were evaluated by optical emission spectroscopy, whereas the microstructures of the samples after hot rolling and heat treatment were observed through metallography. Furthermore, the mechanical properties of the samples were calculated through the tensile test. The results showed a fall in ductility and toughness with respect to reduced thickness and a rise in mechanical strength. It is noteworthy that breaking strength remained unaffected. The JIS-SUP 9 steel is a spring steel, which is the reason for its better mechanical properties (e.g., toughness and ductility) as compared with AISI-1045 steel.
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