Impact of strain-induced martensitic reversion and grain refining on sensitization behavior of high Mn steel was analyzed. The electron backscatter diffraction, optical microscope, and scanning electron microscopy have been used to demonstrate the microstructural examination. The degree of sensitization was examined using double-loop electrochemical potentiokinetic reactivation test. The findings shown that during deformation, fine recoverable grains of strain-induced martensitic and austenite combined formed on the surface of high Mn steel. The degree of sensitization of the cold work samples is significantly higher than that of the as-received sample due to the production of strain-induced martensite. Furthermore, a 15

Biodegradable polymers are substitutes for non-biodegradable polymers manufactured from fossil fuels to reduce plastic waste. Polylactic acid is a promising candidate for biodegradable polymers. Antimicrobial agents such as silver and copper are added to polylactic acid to improve its antimicrobial properties for food packaging applications. In this work, silver nanoparticles were infiltrated into the polylactic acid matrix to form composite films. The presence of silver nanoparticles has enhanced antimicrobial resistance with attested its suitability to be explored like food packaging film. Additionally, the nanoparticle composite film was to be non-toxic and to have high durability. The properties of polylactic acid/silver nanoparticle films were studied as a function of the silver nanoparticle's weight percentage (0%, 5% and 10%). The incorporation of silver nanoparticles in the polylactic acid matrix was established by Fourier transform infrared spectroscopy spectrometer, ultraviolet-visible spectrometer, and field emission-scanning electron microscopy. Fourier transform infrared spectroscopy and ultraviolet-visible spectrum suggest the presence of silver nanoparticles in the composite films. Thermal gravimetric analysis and differential calorimeter analysis reveal the change in degradation and glass transition temperature with an increase in silver nanoparticle concentration. The antibacterial property using the disk diffusion method indicates that polylactic acid/silver nanoparticles (10%) had the highest antibacterial property. Antibacterial action is enhanced when silver nanoparticles are combined with a tiny dose of antibiotics, especially when battling multi-strain-resistant bacteria. Graphical Abstract [Formula: see text]

In this study, the effect of corrosion and wear behaviour of Cr-Mn steel on fine grains were investigated. The sample were solution annealed (SA) for 1 h at 1050 degrees C and then cold rolled (CW) to 30%. Further the cold rolled sample were thermally aged (CW + TA) 900 degrees C for four hours. The findings showed that under the 10 N applied load, wear resistance increased with an increase in hardness and martensite fraction of the cold worked (CW) samples. However, the Cr-Mn steel had the superior wear resistance after thermal ageing (TA). In microstructural examination deformation bands can also be visible in cold work samples. The analysis implies that the gamma-phase is apparent across all peaks within the spectra of SA samples. In instances involving 30% cold work, prominent alpha ' martensite peaks were observed, accompanied by minimal epsilon-martensite peaks. Electrochemical impedance spectroscopy (EIS) analysis discloses a reduction in impedance and a concurrent increase in the defect density of the passive film. The CW+TA structure with good inclusive performances created an early constant hardened layer, which didn't delaminate and peel off prematurely, thereby effectively increasing the wear resistance, according to analysis of the wear mechanism. The results also concluded that the corrosion resistance of CW sample decreases due to SIM formation, however CW+TA sample provide better corrosion resistance due to smaller and refined grain size.

The stacking fault energy (SFE) of face-centered cubic (FCC) alloys is a critical parameter that controls microstructural and crystallographic texture evolution during deformation and annealing treatments. This review focuses on several FCC alloys, aluminum (Al), copper (Cu), austenitic stainless steels (ASSs), and high entropy alloys (HEAs), all of which exhibit varying SFEs. These alloys are often subjected to thermo-mechanical processing (TMP) to enhance their mechanical properties. TMP leads to the evolution of deformation-induced products, such as shear bands (SBs), strain-induced martensite (SIM), and mechanical/deformation twins (DTs) during plastic deformation, while also influencing crystallographic texture. High-medium SFE materials, such as Al and Cu, typically exhibit the evolution of Copper-type texture during room temperature rolling (RTR), while low SFE materials, such as ASSs and HEAs, display Brass-type texture at high reduction ratios. Moreover, the presence of second-phase particles/precipitates can also impact the microstructure and texture evolution in Al and Cu alloys. Particle-stimulated nucleation (PSN) during the annealing treatment has been reported for Al, Cu, ASSs, and HEAs, which causes texture weakening. Another interesting observation in severely deformed Cu alloys is the room-temperature softening phenomenon, which is discussed in the reviewed work. Additionally, plastic deformation and heat treatment of ASSs result in phase transformation, which was not observed in Al, Cu, or HEAs. Furthermore, the dependence of special boundaries in HEAs on plastic deformation temperature, strain rate, and annealing temperature is also discussed. Thus, this review comprehensively reports on the impact of TMP on microstructural and crystallographic texture evolution during plastic deformation and the annealing treatment of Al, Cu, ASSs, and HEAs FCC materials, using results obtained from electron microscopy.

Implantable polymeric hydrogels loaded with immunostimulatory cowpea mosaic virus (CPMV) were fabricated using digital light processing (DLP) printing technology. The CPMV-laden hydrogels were surgically implanted into the peritoneal cavity to serve as depots for cancer slow-release immunotherapy. Sustained release of CPMV within the intraperitoneal space alleviates the need for repeated dosing and we demonstrated efficacy against ovarian cancer in a metastatic mouse model.

The main application in sheet metal forming is austenitic stainless steel (ASS), which is utilised in a various applications, including plate heat exchangers. The martensitic transition can occur during plastic deformation. Temperature, stress and strain are all factors that influence martensite development. The main focus of this research is on the impact of the martensite transformation that occurs during cold working on the corrosion resistance of AISI 316. Corrosion investigation revealed that the martensitic transformation that happens during the cold forming process has a significant impact on the corrosion resistance of AISI 316 ASS plate heat exchangers. The capacity of molybdenum to generate insoluble chloride complexes at the base of pits has been attributed to its role in the creation of passive films. However, due to the cyclic working circumstances of plate heat exchangers, the protective film generated as a result of passivation or repassivation was continuously damaged due to continuous martensitic transformation. The passive layer was continually broken by martensite volume expansion, exposing fresh unprotected surfaces to chlorine-treated water (used in heat exchanger plate as a thermal agent). The martensite transition, which occurs as a result of cold plastic deformation, alters the steel structure as well as its physical and chemical properties. Stainless steel’s magnetic characteristics are highly reliant on the components added to the alloy. Because they have differing corrosion potentials, it is simple for them to become the anode and cathode of a corrosion battery.

One of the most significant sectors of all industrialised economies today is the automotive sector. It offers several people at all economic levels the chance to find employment. In the automotive sector, resistance spot welding is the most used type of welding. The resistance spot weld quality has a significant impact on the structural integrity of a vehicle. Because to complex interactions between electrical, mechanical, thermal, and metallurgical processes, the process is both quick and effective while also being sophisticated. Much effort is always being put forth to produce lightweight materials with excellent strength-ductility combinations because of the growing demand for increased fuel efficiency, decreased CO2 emission, and superior crashworthiness. This paper reviews metallurgical and mechanical performance of resistance spot welds in terms of weld nugget size, load bearing capacity and failure mode, under quasi static loading conditions. It also reviews the effect of process parameters such as welding current, welding time, electrode force and mechanism on the mechanical performance of spot welds.

In the current competitive business scenario, all the companies want to reach at the topmost position by enhancing their flexibility and responsiveness. Companies strive to develop their flexible manufacturing competence (FMC) which reflect their ability to flexibly deploy resources to support their business strategies. In order to do so, there are certain enablers which are needed to be taken into consideration. The dynamics of interdependencies among these enablers also needs to be studied in the course of achieving the goal of the development of superior FMC. To identify these enablers, a comprehensive literature review has been conducted and DEMATEL approach has been used to highlight the importance of these enablers. The analysis unveils the most and least influential and influenced enablers among all the identified enablers. The findings showed that the enablers ‘modularity in products and processes’, which showed the highest value of (D + R) as 0.93, ‘operational improvement practices’, and ‘time-based manufacturing’ having value of (D + R) as 0.87 and 0.85, respectively, are the most critical enablers for the enhancement of FMC of organizations. The study's findings are likely to aid managers in strategically streamlining their efforts toward the path of achieving sustainable competitive advantages.

Purpose The purpose of this study is to examine the effects of sensitization on the metallurgical characteristics of weld joints made up of austenitic stainless steel (AISI 316L) and ferritic stainless steel (AISI 430), using the gas tungsten arc welding (GTAW) process with ER316L filler wires. Design/methodology/approach A non-consumable tungsten electrode with a diameter of 1.6 mm was used during the GTAW procedure. The filler wire, ER316L, was selected based on the recommendation provided in literature. To explore the interconnections among the structure and properties of these weldments, the techniques including scanning electron microscopy and optical analysis have been used. In addition, the sensitization behaviour of the weldments was investigated using the double loop electrochemical potentio-kinetic reactivation (DLEPR) test. Findings Microstructural analyses revealed the occurrences of coarsened grains with equiaxed columnar grains and migrating grain boundaries in the weld zone. The results of the DLEPR test demonstrated that heat affected zone (HAZ) of AISI 430 was more susceptible to sensitization than HAZ of AISI 316L. Microstructure analysis also revealed the precipitation of large amounts of chromium carbide at the grain boundaries region of AISI 430 welded steel, causing more sensitization and, as a result, more failure or breaking at the side of AISI 430 weld in the dissimilar weldment of AISI 316L–AISI 430. Originality/value The present work has been carried out to determine the appropriate welding conditions for joining AISI 316L and AISI 430, as well as the metallurgical properties of the dissimilar weldment formed between AISI 316L and AISI 430. Owing to the difficulties in measuring the performance of these types of dissimilar joints given their unique mechanical and microstructural characteristics, research on the subject is limited.

PURPOSE:To test the hypothesis that cryoablation combined with intratumoral immunomodulating nanoparticles from cowpea mosaic virus (CPMV) as an in situ vaccination approach induces systemic antitumoral immunity in a murine model of hepatocellular carcinoma (HCC). MATERIALS AND METHODS:Mice with bilateral, subcutaneous RIL-175 cell-derived HCCs were randomized to 4 groups: (a) phosphate-buffered saline (control), (b) cryoablation only (Cryo), (c) CPMV-treated only (CPMV), and (d) cryoablation plus CPMV-treated (Cryo + CPMV) (N = 11-14 per group). Intratumoral CPMV was administered every 3 days for 4 doses, with cryoablation performed on the third day. Contralateral tumors were monitored. Tumor growth and systemic chemokine/cytokine levels were measured. A subset of tumors and spleens were harvested for immunohistochemistry (IHC) and flow cytometry. One- or 2-way analysis of variance was performed for statistical comparisons. A P value of <.05 was used as the threshold for statistical significance. RESULTS:At 2 weeks after treatment, the Cryo and CPMV groups, alone or combined, outperformed the control group in the treated tumor; however, the Cryo + CPMV group showed the strongest reduction and lowest variance (1.6-fold ± 0.9 vs 6.3-fold ± 0.5, P < .0001). For the untreated tumor, only Cryo + CPMV significantly reduced tumor growth compared with control (9.2-fold ± 0.9 vs 17.8-fold ± 2.1, P = .01). The Cryo + CPMV group exhibited a transient increase in interleukin-10 and persistently decreased CXCL1. Flow cytometry revealed natural killer cell enrichment in the untreated tumor and increased PD-1 expression in the spleen. Tumor-infiltrating lymphocytes increased in Cryo + CPMV-treated tumors by IHC. CONCLUSIONS:Cryoablation and intratumoral CPMV, alone or combined, demonstrated potent efficacy against treated HCC tumors; however, only cryoablation combined with CPMV slowed the growth of untreated tumors, consistent with an abscopal effect.

The advantage of ferritic stainless steels (FSS’s) over austenitic stainless steels is that they are less expensive alloys. This is due to low or negligible nickel in its alloying element which makes the steel affordable. This type of steel is highly recommended against chloride attack and is also machinable to produce various components for engineering applications. This study examines the effect of various fillers on 430 ferritic stainless steel (FSS). The austenitic (308) and ferritic (410) grades of filler were used to study the weldability, microstructure, mechanical properties, and corrosion resistance using tungsten inert gas welding. The findings showed the emergence of various complex phases in both the weld sample. The sample welded with 410 filler shows acicular ferrite, martensite and austenite. Whereas, austenite and vermicular ferrite are observed in the sample welded with 308 filler. Based on compositions and solidification modes, the mechanical properties of welded joints also vary. It was found that ferritic mode solidified welds dominated in terms of qualities, which was found in 410 filler. In the chloride solution, the behaviour of the pitting corrosion resistance of each weld varied. The sample welded with 410 was superior corrosion resistance. This is due to more δ -ferrite in the weld sample. Whereas, 308 showed poorer resistance against the simulated seawater solution. In 410 welds, a greater degree of sensitization was observed, as compared to 308 welds.

The COVID-19 pandemic caused by SARS-CoV-2 sparked intensive research into the development of effective vaccines, 50 of which have been approved thus far, including the novel mRNA-based vaccines developed by Pfizer and Moderna. Although limiting the severity of the disease, the mRNA-based vaccines presented drawbacks, such as the cold chain requirement. Moreover, antibody levels generated by these vaccines decline significantly after 6 months. These vaccines deliver mRNA encoding the full-length spike (S) glycoprotein of SARS-CoV-2, but must be updated as new strains and variants of concern emerge, creating a demand for adjusted formulations and booster campaigns. To overcome these challenges, we have developed COVID-19 vaccine candidates based on the highly conserved SARS CoV-2, 809-826 B-cell peptide epitope (denoted 826) conjugated to cowpea mosaic virus (CPMV) nanoparticles and bacteriophage Qβ virus-like particles, both platforms have exceptional thermal stability and facilitate epitope delivery with inbuilt adjuvant activity. We evaluated two administration methods: subcutaneous injection and an implantable polymeric scaffold. Mice received a prime–boost regimen of 100 μg per dose (2 weeks apart) or a single dose of 200 μg administered as a liquid formulation, or a polymer implant. Antibody titers were evaluated longitudinally over 50 weeks. The vaccine candidates generally elicited an early Th2-biased immune response, which stimulates the production of SARS-CoV-2 neutralizing antibodies, followed by a switch to a Th1-biased response for most formulations. Exceptionally, vaccine candidate 826-CPMV (administered as prime-boost, soluble injection) elicited a balanced Th1/Th2 immune response, which is necessary to prevent pulmonary immunopathology associated with Th2 bias extremes. While the Qβ-based vaccine elicited overall higher antibody titers, the CPMV-induced antibodies had higher avidity. Regardless of the administration route and formulation, our vaccine candidates maintained high antibody titers for more than 50 weeks, confirming a potent and durable immune response against SARS-CoV-2 even after a single dose.

Effect of strain path and crystallographic texture on electrochemical properties of cold-rolled Ti-15V-3Cr-3Sn-3Al (all elements in weight%, designated as Ti-15333) alloy has been studied in the present investigation. The as-received specimens with and without solution annealing (SA) were subjected to different strain paths to reduction ratio (RR) of 40% and 80%. The microstructure showed the presence of shear bands (SBs) in all the deformed specimens and its fraction increased with increase in the RR. With the increase in deformation, α- and γ- fibers were observed in all the specimens. Electrochemical potentio-dynamic tests followed by open circuit voltage were used to investigate the passivity and pitting corrosion in 3.5% NaCl solution for both the undeformed (as-received, SA) and deformed Ti-15333 alloy specimens. A complementary assessment was employed to analyze the influence of work-hardening on passivity and pitting corrosion behaviors of Ti-15333 alloy systematically, combined with additional investigation of electrochemical impedance spectroscopy (EIS). High corrosion resistance was observed for the SA specimen than non-SA (as-received) specimen. Increase in the RR from 40% to 80% increased the corrosion rate for all the strain paths, except multi-step cross-rolled (MSCR). Corrosion resistance of the 80% deformed specimens were dependent on both the evolved microstructure (SBs, grain fragmentation) as well as crystallographic texture. Multi-step cross rolling resulted in the formation of a strong Rotated Cube ({100}<110>) texture, which was expected to be the reason for its enhanced corrosion resistance.

The effects of thermal aging and prior cold work at 700 °C on the kinetics of sensitization (i.e., corrosion failure) of high-manganese austenitic stainless steel have been studied by conducting microstructural analysis, transmission electron microscopy analysis, and double-loop potentiostatic reactivation analysis. Thermal aging at 700 °C caused an increase in preferential grain boundary attack (dual and ditch type) and degree of sensitization, and the intensity of these effects increased with the increase in time duration of thermal aging. With cold working, a widespread grain area attack has been found with no preferential grain boundary attack; however, an increase in degree of sensitization values has been observed. Transmission electron microscopy and energy-dispersive x-ray spectroscopy showed the presence of carbides on the grain area, i.e., transgranular carbide precipitation. The findings conclude that the cold-worked thermal-aged high manganese austenitic stainless steel becomes susceptible to intergranular corrosion failure due to sensitization and transgranular corrosion.

Biologics — medications derived from a biological source — are increasingly used as pharmaceuticals, for example, as vaccines. Biologics are usually produced in bacterial, mammalian or insect cells. Alternatively, plant molecular farming, that is, the manufacture of biologics in plant cells, transgenic plants and algae, offers a cheaper and easily adaptable strategy for the production of biologics, in particular, in low-resource settings. In this Review, we discuss current vaccination challenges, such as cold chain requirements, and highlight how plant molecular farming in combination with advanced materials can be applied to address these challenges. The production of plant viruses and virus-based nanotechnologies in plants enables low-cost and regional fabrication of thermostable vaccines. We also highlight key new vaccine delivery technologies, including microneedle patches and material platforms for intranasal and oral delivery. Finally, we provide an outlook of future possibilities for plant molecular farming of next-generation vaccines and biologics.

In recent days, cantor alloy/High entropy alloys (HEAS) have come a long way, and key challenges have developed more frequently when HEA welding is required. In this critical evaluation of the HEAs welding, we seek to report the HEAs weldability under BM and WM composition, welding parameters and their distinctive corrosion behaviour. The current advancements and issues in various HEAS welding phenomena are comprehensively studied, with the microstructures, mechanical characteristic, and functional performances of the joints all taken into account. In addition to reducing the production of intermetallic phases, personalizing welded components, and improving properties of joints, HEAS fillers have shown great potential.

This paper review the effects of cold rolling, thermal ageing & grain refinement on wear resistance of austenitic stainless steel (ASS). ASS is generally classified into two major series i.e. 300 and 200 series. Metallic materials wear resistance is mostly determined by their hardness and H/E ratio. As per reports, the better the H/E ratio, the greater the wear resistance. As plastic deformation causes crystalline defects such as dislocations, resulting in reduced crystalline integrity, which increases the H/E proportion generated by cold-work that did not help to improve the wear resistance. Paper also shows that the microstructure of nearly disorder and intergranular fine austenite grains with higher yielding strength and elongation provide higher wear resistance at high temperature (250 °C), which was attributed to twinning driven plasticity displaced in fine austenite grains. The annealed fine grain (FG) sample exhibits a greater hardness and worn sub-surface than the course grains (CG) sample under identical test conditions, showing improved wear resistance.

Corrosion resistance across a wide temperature range, increased physical, mechanical, and tribological capabilities, variable surface hydrophobicity, and an attractive appearance are all advantages of electrodeposited metal matrix composite coatings (MMCs). As a result, several studies have been conducted to evaluate the various physical, mechanical, biochemical, electrochemistry, and thermodynamics characteristics of nanocrystalline composite material, generated on a variety of substrates with numerous electrodeposition settings. In this review paper, the current literatures on wear rate of electrode-posited Ni-based coatings made of composite materials are being reviewed. More specifically, the research papers on weight management, wear resistance, coefficient of friction, surface roughness, hardness and associated deterioration methods has been identified and reviewed. The observations showed that nano-composite films offer substantially superior wear resistance than magnesium alloys and pure nickel coatings due to the diffraction stiffening and grain refining effects. Also, abrasion is the main wear process for nano-composite coatings, whereas adhesion wear is the primary wear arrangement for magnesium alloys and major wear mechanism for pure nickel coatings is exfoliation wear.

Owing to the fluctuating demands of customers and intensified competition, organizations are searching ways to enhance their flexible manufacturing competence (FMC) as it has been recognized as one of the most important approaches to handle the aforementioned situations. The existing literature provides several factors that significantly affect FMC, however, the interrelationships among these factors are somewhat unexplored. The insights to the interactions among these factors could provide crucial managerial implications that could pave ways for success of organizations in today’s uncertain business environment. To this end, the present work makes an effort and highlights the important factors and investigates their interactions with each other for the enhancement of FMC of organizations. In this paper, the interpretive structural modelling (ISM) methodology has been implemented to explore the interactions and develop a structural model depicting the hierarchy of the factors. Further, MICMAC analysis has been used to categorize the factors into different groups based on their driving and dependence powers.