JOM最新文献

The slag crust thickness on the hot surface of the copper cooling staves in the high thermal load areas of a blast furnace is crucial for the safe operation and long campaign of the blast furnace. In this study, a heat transfer model for the slag crust and the copper cooling staves in a blast furnace is established. The temperature distribution in the slag crust and copper cooling staves is calculated and the temperature variation in the copper cooling stave with the change of slag crust thickness is also studied. The temperature measurement data of the copper cooling staves are fitted with the corresponding slag crust thicknesses, and an online model for calculating the slag crust thickness is established. The slag crust thickness is displayed in the form of a contour map by unfolding the slag crust and the copper cooling staves along the circumferential direction of blast furnace, by which the visualization of slag crust thickness distribution and the variation in slag crust thickness with time can be achieved. This online visualization model can help operators accurately judge the locations where the slag crust thickness fluctuates severely, and take timely and effective measures to guarantee the normal operation condition.

Grain size has a significant impact on the superelasticity of alloys. Large-sized grains show superior superelastic properties because the grain boundaries are minimized and the grain constraints caused by triple junctions are reduced. Cyclic heat treatment (CHT) is commonly employed to generate subgrains, whose energy can be consumed to induce abnormal grain growth (AGG) and obtain large-sized grains. In this paper, the effects of adding Cu on the subgrain characteristics during AGG and microstructural evolution of FeMnAlNi-based superelastic alloys were systematically investigated. The addition of Cu reduced the temperature at which the γ phase precipitates and altered the morphology of the γ phase. After the dissolution of the refined γ phases, the average subgrain size became smaller and misorientation increased. These characteristic subgrain changes improved the driving force for AGG and accelerated the grain boundary migration rate. Due to the addition of Cu, the maximum grain size reached 28.2 mm. This study provides a new method for the preparation of FeMnAlNi-based superelastic alloys with large-sized grains.

CM247LC alloy has been processed through two different routes, viz. investment casting and powder metallurgical route. The powder metallurgical route involves production of powder through inert gas atomization followed by consolidation using hot isostatic pressing (HIP). A comparative study has been carried out on microstructure and mechanical properties of the material processed through both routes to assess the efficacy of the powder metallurgical process as a viable alternative to the investment casting route. The HIPed material is free from deleterious prior particle boundaries and coarse primary γ′ and has finer grain size compared to cast material. The HIPed material exhibits higher strength and ductility at room temperature, whereas ductility of HIPed alloy at 760°C is less than for the cast alloy. Detailed microstructural analysis and thermodynamic calculation reveal that network of carbides at the grain boundary of HIPed material causes lower ductility although HIPed material exhibits better strength than cast material, even at higher temperature. This study establishes the potential of HIP process to manufacture near net shape components of complex configuration through powder metallurgy route.

Interpenetrating polymer hydrogel networks (IPNs) present a significant advancement in the role of biomaterials with tailored properties for wearable sensors, particularly in developing non-invasive real-time monitoring devices for healthcare and fitness. This study investigates the synthesis processing and characterization of highly stretchable and elastomeric hydrogel IPNs, focusing on simplifying the synthesis by dual cross-linking of ionic and covalent polymeric backbones in ambient conditions. The hydrogels were tested for their rheological properties, mechanical behavior, and analyte sensitivity. Integrating these hydrogels into wearable sensors offers novel opportunities for continuous monitoring of physiological parameters and early detection of changes in health conditions. Rheology reveals shear thinning behavior and successful ambient cross-linking capabilities, while mechanical testing demonstrated remarkable stretchability and resilience even under cyclic tensile stress. The hydrogel's sensitivity and selectivity for biosensing were showcased with distinct responses to various analytes such as glucose, saline, and ion gradients. Further exploration and optimization of the synthesis parameters are essential for unlocking the full potential of these materials in biomedical and sensing applications, advancing personalized healthcare and disease monitoring.

Approximately 10–15% of the world’s steel production is derived from small industries. While ladle furnaces contribute to maintaining a generally good quality of refined steel, new challenges arise, especially when striving for very low sulfur percentages in steel. To address this, the study explores the impact of process parameters such as aluminum, silicon, and basicity in reducing sulfur content. Three interconnected equilibrium/adiabatic stoichiometric-reactor-based approaches describe the overall ladle steel-making process. The macro-programming facility of FactSage™ software was used to determine the refining behaviors of the ladle steel-making processes. The model’s predicted endpoint, manganese, sulfur, oxygen, and aluminum content, agreed with plant data. This efficient model is a valuable guiding tool for ladle steelmaking industries with a 10–15 ton capacity.