Surface hot shortness is of concern in scrap-based electric arc furnace (EAF) steelmaking. The excessive amount of residual copper (Cu) in the steel scrap enriches during the oxidation of the solid steel, and as a result a Cu-rich layer could form which causes inter-granular grain boundary cracking. Other residuals can also influence hot-shortness. Ni is known to improve the resistance to hot shortness whereas Sn is known to worsen it. In this paper, the mechanism through which nickel (Ni) counters the detrimental effects of tin (Sn) on surface hot shortness are investigated in detail. A series of Fe-0.3 wt%Cu-x wt%Ni-0.03 wt%Sn alloys with x content ranging from 0.03 to 0.45 wt% was oxidized in air at 1,423 K (1,150°C) for 60, 300 and 600 seconds using thermogravimety (TG). The microstructure investigation under scanning electron microscopy (SEM) showed that, significant grain boundary cracking was suppressed by eliminating the highly embrittling Sn containing Cu-rich liquid, through increasing Cu solubility and/or solidifying the liquid phase by the presence of sufficient amount of Ni. Occlusion and decreased oxidation kinetics caused by Ni were shown not to play a significant role. A previous proposed diffusion numerical model was applied to the Fe-Cu-Ni-Sn system to quantitatively support experimental results and provide insight to the enrichment kinetics at the oxide/metal interface.

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ICU. Studies have shown that implementation of the bundle, including a ventilator weaning protocol and maintaining light levels of sedation, improve patient outcomes. However, "real-world" application of the A-F Bundle had been unsuccessful at the study site prior to the multidisciplinary quality improvement project. METHOD:This quality improvement project was conducted in a 31-bed adult ICU beginning in February 2021. First, the electronic medical record, documentation, and policies/ procedures were redesigned to follow the A-F Bundle elements. Then, the multidisciplinary leadership team, including nursing, respiratory therapy, pharmacy, and administration, created a spontaneous awakening trial (SAT) and spontaneous breathing trial (SBT) protocol. Lastly, extensive multidisciplinary education was provided to nursing (6 hours), respiratory therapy (1.5 hours), and prescribers (1 hour) to review the evidenced-based recommendations, A-F Bundle, and SAT/SBT protocol. This quality improvement project then compared the amount of propofol used per patient, ventilator days, ICU length of stay (LOS), hospital LOS, and mortality pre (January 2021) and post (June 2021) completion of the project. RESULTS:Twenty-five adults were included in the pre-group and 29 in the post. Median amount of propofol used per ventilator day decreased from 11 mcg/kg/min to 9 mcg/kg/ min when comparing the pre to the post-group. This decrease was also seen in median amount of propofol used per patient (600 mL to 400 mL) and per ventilator day (150 mL vs. 83 mL). Ventilator days were the same between the two groups (5 days). However, median ICU LOS and hospital LOS were lower in the post-group (ICU LOS: 14 vs. 9 days, hospital LOS 20 vs. 14 days). Morality rate in the pre-group was 64% vs. 31% in the post-group. CONCLUSIONS:The studied quality improvement project, which included A-F bundle implementation and multidisciplinary education, decreased sedative use and LOS.