Twinning-Induced Plasticity Aided High Ductile Duplex Stainless Steel

Extended ductility over 70 pct was realized in duplex stainless steel by implementing twinning-induced plasticity (TWIP). The steel also exhibited the tensile strength over 800 MPa. The steel chemistry was designed so that the stacking fault energy of austenite was high enough to induce TWIP during deformation. After the initial decrease, the strain hardening rate increased at high tensile strains above ~30 pct. The microstructures of austenite at such high strains were manifested by well-developed primary twins and nanotwins between them, which effectively block dislocation motion. This observation ensures that extended ductility and high strength of a newly designed duplex stainless steel are originated from TWIP in austenite.     

Hardware-in-the-loop simulation for a production system

This paper proposes a hardware-in-the-loop simulation (HILS) approach for the design and verification of a production system. The design of a production system involves two major activities: mechanical design (device specification and layouts) and electrical design (device behaviour and system control). Conventionally, the mechanical and electrical design activities have been performed sequentially, wasting time. We propose a concurrent procedure of mechanical and electrical design based on the HILS methodology to cope with this problem. The proposed HILS approach provides two major benefits: (1) the verified control program can be directly used for the real plant with minor adaptations; and (2) the verified 3D layout model can be used to generate the detailed drawings for the implementation of the plant. We can minimise the stabilisation time of a production system, since most mechanical and electrical errors can be found and fixed using HILS.     

Thermal treatment effect on the magnetoelectric properties of (Ni0.5Zn0.5)Fe2O4/Pt/Pb(Zr0.3Ti0.7)O3 heterostructured thin films

Magnetoelectric (ME) property modulation in heterostructured (Ni_0.5Zn_0.5)Fe₂O₄/Pt/Pb(Zr_0.3Ti_0.7)O₃ (NZFO/Pt/PZT) thin films on platinized Si substrate by thermal annealing condition variation was studied. In an attempt to prevent interfacial reaction between NZFO and PZT layers during high temperature annealing, thin Pt layer was deposited which can serve as inter-diffusion barrier as well as electrode. The ferroelectric, magnetic, and ME properties of the heterostructured film were noticeably modulated due to microstructural evolution and clamping relaxation developed during thermal annealing process. Room temperature ME voltage coefficient of the heterostructured thin films was enhanced with increasing annealing temperature and reached to 29 mV/cm·Oe when annealed at 650 °C.     

Flexible Piezoelectric Acoustic Sensors and Machine Learning for Speech Processing

Flexible piezoelectric acoustic sensors have been developed to generate multiple sound signals with high sensitivity, shifting the paradigm of future voice technologies. Speech recognition based on advanced acoustic sensors and optimized machine learning software will play an innovative interface for artificial intelligence (AI) services. Collaboration and novel approaches between both smart sensors and speech algorithms should be attempted to realize a hyperconnected society, which can offer personalized services such as biometric authentication, AI secretaries, and home appliances. Here, representative developments in speech recognition are reviewed in terms of flexible piezoelectric materials, self-powered sensors, machine learning algorithms, and speaker recognition.     

Dissolution kinetics of alumina in molten CaO–Al2O3–FetO–MgO–SiO2 oxide representing the RH slag in steelmaking process

In order to effectively remove alumina inclusions suspending in ultra-low C steel during RH process, the dissolution kinetics of alumina in molten CaO–Al₂O₃–Fe_tO–MgO–SiO₂ oxide was investigated. A crucible dissolution technique was used where the alumina crucible was allowed to dissolve in the slag of various conditions ((% CaO)/(% Al₂O₃), (% Fe_tO), temperature). The obtained data were interpreted using a kinetic mass transport equation to obtain the mass transport coefficient (k_m) in each condition. Increasing (% CaO)/(% Al₂O₃), (% Fe_tO), and temperature increased the dissolution rate as well as the k_m provided that the slag composition is not close to its saturation composition by alumina. In order to simulate the dissolution of alumina inclusion in the RH slag, which cannot be measured by a confocal scanning laser microscopy (CSLM) at present due to the opaqueness of the slag, the modified invariant interface approximation was employed. Along with the obtained k_m, the viscosity of slag, and a reference experiment using the CSLM, the dissolution kinetics of alumina inclusion in the Fe_tO-containing RH slag was predicted. The time required for the dissolution of alumina inclusions from liquid steel to RH slag was discussed.     

Drivers of change in groundwater resources: a case study of the Indian Punjab

Indian Punjab, a strategically important region from India’s national food security standpoint, is increasingly the focus of attention for academics and policymakers because of serious concerns about over-exploitation of its groundwater resources. Currently, policy makers and agricultural researchers/scientists in India are in a fix to prescribe an alternative, probably more sustainable, crop-mix to farmers that can save water while maintaining farm incomes. Using primary data from 120 farmers, this paper evaluates the current situation of groundwater resources in Punjab, and outlines the major socio-economic factors that have a significant association with the change in the groundwater depth in this region. General ANOVA regression results suggest that groundwater depth varied significantly with respect to agro-climatic regions, crop diversity, and farmer education. Crop diversity had an inverse relationship with groundwater depth whereas the association between farmer education and groundwater depth was non-linear although in the case of Gurdaspur, they showed a direct relationship. In the central zone of Indian Punjab, groundwater level on 92% of the farms had depleted by more than 0.60 m annually between 2000 and 2010, while the current state of groundwater resources in the other two regions was not so serious and are manageable for the time being. However, if the existing policy framework for groundwater resources in the state, which allows the state government to release 0.11 million more connections to farmers, putting much pressure not only on the groundwater resources but also burdening the state exchequer, continues, Punjab may end up losing all its groundwater resources for ever. Considering this alarming situation, one-fifth of the farmers surveyd agreed to delay the sowing of rice by another 2 weeks i.e. up to 30 June which could save the fast depleting groundwater resources in Punjab.     

Quality-by-design approach for the development of telmisartan potassium tablets

A quality-by-design approach was adopted to develop telmisartan potassium (TP) tablets, which were bioequivalent with the commercially available Micardis^® (telmisartan free base) tablets. The dissolution pattern and impurity profile of TP tablets differed from those of Micardis^® tablets because telmisartan free base is poorly soluble in water. After identifying the quality target product profile and critical quality attributes (CQAs), drug dissolution, and impurities were predicted to be risky CQAs. To determine the exact range and cause of risks, we used the risk assessment (RA) tools, preliminary hazard analysis and failure mode and effect analysis to determine the parameters affecting drug dissolution, impurities, and formulation. The range of the design space was optimized using the face-centered central composite design among the design of experiment (DOE) methods. The binder, disintegrant, and kneading time in the wet granulation were identified as X values affecting Y values (disintegration, hardness, friability, dissolution, and impurities). After determining the design space with the desired Y values, the TP tablets were formulated and their dissolution pattern was compared with that of the reference tablet. The selected TP tablet formulated using design space showed a similar dissolution to that of Micardis^® tablets at pH 7.5. The QbD approach TP tablet was bioequivalent to Micardis^® tablets in beagle dogs.     

Effects of Fe2O3 doping on structural and electrical properties of 8 mol% yttria-stabilized zirconia electrolyte for solid oxide fuel cells

Journal of Materials Science: Materials in Electronics - The effects of doping a trace of Fe2O3 on the structural and electrical properties of 8 mol% yttria-stabilized zirconia (8YSZ) are...