microstructure evolution during heat treatments

Funding Information: Authors acknowledge the Portuguese Fundação para a Ciência e a Tecnologia (FCT – MCTES) for its financial support via the project UID/EMS/00667/2019 (UNIDEMI). JPO acknowledges funding by national funds from FCT - Fundação para a Ciência e a Tecnologia, I.P., in the scope of the projects LA/P/0037/2020 , UIDP/50025/2020 and UIDB/50025/2020 of the Associate Laboratory Institute of Nanostructures, Nanomodelling and Nanofabrication – i3N. Funding of CENIMAT/i3N by national funds through the FCT-Fundação para a Ciência e a Tecnologia, I.P., within the scope of Multiannual Financing of R&D Units, reference UIDB/50025/2020–2023 is also acknowledge. FWCF acknowledges Fundação para a Ciência e a Tecnologia ( FCT-MCTES ) for funding the Ph.D. Grant 2022.13870. BD. The authors acknowledge DESY (Hamburg, Germany), a member of the Helmholtz Association HGF, for the provision of experimental facilities. Beamtime was allocated for proposal I-20210986 EC. The research leading to this result has been supported by the project CALIPSOplus under the Grant Agreement 730872 from the EU Framework Programme for Research and Innovation HORIZON 2020. This activity has received funding from the European Institute of Innovation and Technology (EIT) Raw Materials through the project Smart WAAM: Microstructural Engineering and Integrated Non-Destructive Testing. YZ acknowledges the National Natural Science Foundation of China ( 51601091 ), the Natural Science Foundation of Jiangsu Province ( BK 20160826 ), the Six Talent Peaks Project of Jiangsu Province ( 2017-XCL-051 ), the Fundamental Research Funds for the Central Universities ( 30917011106 ), and Key Research and Development Plan of Jiangsu Province ( BE 2020085 ). Funding Information: Authors acknowledge the Portuguese Fundação para a Ciência e a Tecnologia (FCT – MCTES) for its financial support via the project UID/EMS/00667/2019 (UNIDEMI). JPO acknowledges funding by national funds from FCT - Fundação para a Ciência e a Tecnologia, I.P. in the scope of the projects LA/P/0037/2020, UIDP/50025/2020 and UIDB/50025/2020 of the Associate Laboratory Institute of Nanostructures, Nanomodelling and Nanofabrication – i3N. Funding of CENIMAT/i3N by national funds through the FCT-Fundação para a Ciência e a Tecnologia, I.P. within the scope of Multiannual Financing of R&D Units, reference UIDB/50025/2020–2023 is also acknowledge. FWCF acknowledges Fundação para a Ciência e a Tecnologia (FCT-MCTES) for funding the Ph.D. Grant 2022.13870. BD. The authors acknowledge DESY (Hamburg, Germany), a member of the Helmholtz Association HGF, for the provision of experimental facilities. Beamtime was allocated for proposal I-20210986 EC. The research leading to this result has been supported by the project CALIPSOplus under the Grant Agreement 730872 from the EU Framework Programme for Research and Innovation HORIZON 2020. This activity has received funding from the European Institute of Innovation and Technology (EIT) Raw Materials through the project Smart WAAM: Microstructural Engineering and Integrated Non-Destructive Testing. YZ acknowledges the National Natural Science Foundation of China (51601091), the Natural Science Foundation of Jiangsu Province (BK 20160826), the Six Talent Peaks Project of Jiangsu Province (2017-XCL-051), the Fundamental Research Funds for the Central Universities (30917011106), and Key Research and Development Plan of Jiangsu Province (BE 2020085). Publisher Copyright: © 2023 The Author(s)The study reports that the combined use of in situ interlayer hot forging and post-deposition heat treatment (PDHT) could alter the typical coarse and oriented microstructure of the Ni-based superalloy 625 obtained by arc plasma directed energy deposition (DED) to a fine and non-oriented condition. In situ synchrotron X-ray diffraction and electron backscatter diffraction showed that the high-temperature (1100 °C/ 1 h) PDHT induced significant recrystallization, leading to grain refinement and low texture index, while partially dissolving deleterious Laves and δ phases. Low-temperature (980 °C/ 1 h) PDHT had a limited effect on the grain size refinement and induced the formation of secondary phases. It is shown that conventional heat treatments applied to Ni-based superalloy 625 obtained by arc plasma DED are not conducive to optimized microstructure features. In situ hot forging induced enough crystal defects to promote static recrystallization during PDHT. Besides, high-temperature PDHT met the AMS 5662 grain size requirements.publishersversionpublishe

process development and microstructure effects

JPO acknowledges funding by national funds from FCT - Fundação para a Ciência e a Tecnologia, Portugal, I.P. in the scope of the project LA/P/0037/2020. The authors acknowledge DESY (Hamburg, Germany), a member of the Helmholtz Association HGF, for the provision of experimental facilities. Beamtime was allocated for proposal I-20210986 EC. This activity has received funding from the European Institute of Innovation and Technology (EIT) Raw Materials through the project Smart WAAM: Microstructural Engineering and Integrated Non-Destructive Testing. YZ acknowledges the National Natural Science Foundation of China (51601091), the Natural Science Foundation of Jiangsu Province (BK 20160826), the Six Talent Peaks Project of Jiangsu Province (2017-XCL-051), the Fundamental Research Funds for the Central Universities (30917011106), and Key Research and Development Plan of Jiangsu Province (BE 2020085). Funding Information: Authors acknowledge the Portuguese Fundação para a Ciência e a Tecnologia (FCT – MCTES) , Portugal, for its financial support via the project UID/EMS/00667/2019 (UNIDEMI). JPO acknowledges funding by national funds from FCT - Fundação para a Ciência e a Tecnologia, Portugal, I.P., in the scope of the projects LA/P/0037/2020 , UIDP/50025/2020 and UIDB/50025/2020 of the Associate Laboratory Institute of Nanostructures, Nanomodelling and Nanofabrication – i3N. FWCF acknowledges Fundação para a Ciência e a Tecnologia ( FCT-MCTES ), Portugal, for funding the Ph.D. Grant 2022.13870. BD . The authors acknowledge DESY (Hamburg, Germany), a member of the Helmholtz Association HGF, for the provision of experimental facilities. Beamtime was allocated for proposal I-20210986 EC. The research leading to this result has been supported by the project CALIPSOplus under the Grant Agreement 730872 from the EU Framework Programme for Research and Innovation HORIZON 2020. This activity has received funding from the European Institute of Innovation and Technology (EIT) Raw Materials through the project Smart WAAM: Microstructural Engineering and Integrated Non-Destructive Testing. YZ acknowledges the National Natural Science Foundation of China (51601091), the Natural Science Foundation of Jiangsu Province (BK 20160826), the Six Talent Peaks Project of Jiangsu Province (2017-XCL-051), the Fundamental Research Funds for the Central Universities (30917011106), and Key Research and Development Plan of Jiangsu Province (BE 2020085). Publisher Copyright: © 2023 The AuthorsThe typical as-built coarse and cube-oriented microstructure of Inconel® 625 parts fabricated via arc-based directed energy deposition (DED) induces anisotropic mechanical behavior, reducing the potential applications of arc-based DEDed Inconel® 625 in critical components. In this sense, the present work aimed to reduce the grain size and texture by applying an in situ interlayer hot forging (HF) combined with post-deposition heat treatments (PDHT). The produced samples were characterized through optical microscopy, scanning electron microscopy coupled with electron backscatter diffraction, synchrotron X-ray diffraction, and Vickers microhardness. Also, a dedicated deformation tool was designed and optimized via a finite element method model considering the processing conditions and thermal cycle experienced by the material. It is shown that the in situ interlayer deformation induced a thermo-mechanical-affected zone (dynamic recrystallized + remaining deformation, with a height of ≈ 1.2 mm) at the bead top surface, which resulted in thinner aligned grains and lower texture index in relation to as-built DED counterpart. In addition, the effects of solution (1100 °C/ 1 h) and stabilization (980 °C/ 1 h) PDHTs on the Inconel® 625 HF-DEDed parts were also analyzed, which promoted fine and equiaxed static recrystallized grains without cube orientation, comparable to wrought material. Therefore, the HF-DED process significantly refined the typical coarse and highly oriented microstructure of Ni-based superalloys obtained by arc-based DED.publishersversionpublishe

A Realist Perspective on AI-era Public Management

Recent years have witnessed a number of significant ideas and approaches to addressing the shortcomings of the New Public Management paradigm. Three of these recent ideas, which include Digital Era Governance, Public Value Management, and New Public Governance, emphasise partnerships collaboration and engagement of citizens; performance governance and innovation and recognize the transformational potentials of digital technologies. Artificial Intelligence (AI) is one of the digital technologies attracting the greatest interest in public administration in terms of its potential impact. There are already a number of reports on how AI is being deployed in the public sector with good outcomes. By employing a realist review approach, this study investigates the specific mechanisms across post-NPM, organisational, individual and innovation contexts which are associated with positive outcomes from AI initiatives in the public sector. The study further examined the specific applications of AI initiatives within Post-NPM agendas. Our findings provide some empirical evidence for a better understanding of the conditions and where to target AI-based solutions in post-NPM context for positive outcomes

Post-puff respiration measures on smokers of different tar yield cigarettes

The purpose of this study was to determine the effect of different tar yield cigarette brands on the post-puff inhalation/exhalation depth and duration for established smokers of the brands. The study was conducted with 74 established smokers of 1–17 mg Federal Trade Commission (FTC) tar products. The subjects were participating in a five-day inpatient clinical biomarker study during which time they were allowed to smoke their own brand of cigarette whenever they wished. On two separate days, the subjects' breathing pattern was measured using respiratory inductive plethysmography while they smoked one cigarette. This enabled the measurement of the post-puff inhalation volume, exhalation volume, inhalation duration, and exhalation duration for each subject after each puff on two of their own brand of cigarettes

The in vitro toxicology of Swedish snus

Three commercial brands of Swedish snus (SWS), an experimental SWS, and the 2S3 reference moist snuff were each tested in four in vitro toxicology assays. These assays were: Salmonella reverse mutation, mouse lymphoma, in vitro micronucleus, and cytotoxicity. Water extractions of each of the 5 products were tested using several different concentrations; the experimental SWS was also extracted using dimethyl sulfoxide (DMSO). Extraction procedures were verified by nicotine determinations. Results for SWS in the mutagenicity assays were broadly negative: there were occasional positive responses, but these were effectively at the highest concentration only (concentrations well above those suggested by regulatory guidelines), and were often associated with cytotoxicity. The 2S3 reference was unequivocally positive in one of the three conditions of the micronucleus assay (MNA), at the highest concentration only. Positive controls produced the expected responses in each assay. The SWS data are contrasted with data reported for combusted tobacco in the form of cigarettes, where strongly positive responses have been routinely reported for mutagenicity and cytotoxicity. These negative findings in a laboratory setting concur with the large amount of epidemiological data from Sweden, data showing that SWS are associated with considerably lower carcinogenic potential when compared with cigarettes

Systematic review of the epidemiological evidence comparing lung cancer risk in smokers of mentholated and unmentholated cigarettes

<p>Abstract</p> <p>Background</p> <p>US mentholated cigarette sales have increased considerably over 50 years. Preference for mentholated cigarettes is markedly higher in Black people. While menthol itself is not genotoxic or carcinogenic, its acute respiratory effects might affect inhalation of cigarette smoke. This possibility seems consistent with the higher lung cancer risk in Black men, despite Black people smoking less and starting smoking later than White people. Despite experimental data suggesting similar carcinogenicity of mentholated and non-mentholated cigarettes, the lack of convincing evidence that mentholation increases puffing, inhalation or smoke uptake, and the similarity of lung cancer rates in Black and White females, a review of cigarette mentholation and lung cancer is timely given current regulatory interest in the topic.</p> <p>Methods</p> <p>Epidemiological studies comparing lung cancer risk in mentholated and non-mentholated cigarette smokers were identified from MedLine and other sources. Study details were extracted and strengths and weaknesses assessed. Relative risk estimates were extracted, or derived, for ever mentholated use and for long-term use, overall and by gender, race, and current/ever smoking, and meta-analyses conducted.</p> <p>Results</p> <p>Eight generally good quality studies were identified, with valid cases and controls, and appropriate adjustment for age, gender, race and smoking. The studies afforded good power to detect possible effects. However, only one study presented results by histological type, none adjusted for occupation or diet, and some provided no results by length of mentholated cigarette use.</p> <p>The data do not suggest any effect of mentholation on lung cancer risk. Adjusted relative risk estimates for ever use vary from 0.81 to 1.12, giving a combined estimate of 0.93 (95% confidence interval 0.84-1.02, n = 8), with no increase in males (1.01, 0.84-1.22, n = 5), females (0.80, 0.67-0.95, n = 5), White people (0.87, 0.75-1.03, n = 4) or Black people (0.90, 0.73-1.10, n = 4). Estimates for current and ever smokers are similar. The combined estimate for long-term use (0.95, 0.80-1.13, n = 4) again suggests no effect of mentholation.</p> <p>Conclusion</p> <p>Higher lung cancer rates in Black males cannot be due to their greater preference for mentholated cigarettes. While some study weaknesses exist, the epidemiological evidence is consistent with mentholation having no effect on the lung carcinogenicity of cigarettes.</p

Constrained pre-equalization accounting for multi-path fading emulated using large RC networks: applications to wireless and photonics communications

Multi-path propagation is modelled assuming a multi-layer RC network with randomly allocated resistors and capacitors to represent the transmission medium. Due to frequency-selective attenuation, the waveforms associated with each propagation path incur path-dependent distortion. A pre-equalization procedure that takes into account the capabilities of the transmission source as well as the transmission properties of the medium is developed. The problem is cast within a Mixed Integer Linear Programming optimization framework that uses the developed nominal RC network model, with the excitation waveform customized to optimize signal fidelity from the transmitter to the receiver. The objective is to match a Gaussian pulse input accounting for frequency regions where there would be pronounced fading. Simulations are carried out with different network realizations in order to evaluate the sensitivity of the solution with respect to changes in the transmission medium mimicking the multi-path propagation. The proposed approach is of relevance where equalization techniques are difficult to implement. Applications are discussed within the context of emergent communication modalities across the EM spectrum such as light percolation as well as emergent indoor communications assuming various modulation protocols or UWB schemes as well as within the context of space division multiplexing

Scientific assessment of the use of sugars as cigarette tobacco ingredients: A review of published and other publicly available studies

Sugars, such as sucrose or invert sugar, have been used as tobacco ingredients in American-blend cigarettes to replenish the sugars lost during curing of the Burley component of the blended tobacco in order to maintain a balanced flavor. Chemical-analytical studies of the mainstream smoke of research cigarettes with various sugar application levels revealed that most of the smoke constituents determined did not show any sugar-related changes in yields (per mg nicotine), while ten constituents were found to either increase (formaldehyde, acrolein, 2-butanone, isoprene, benzene, toluene, benzo[k]fluoranthene) or decrease (4-aminobiphenyl, N-nitrosodimethylamine, N-nitrosonornicotine) in a statistically significant manner with increasing sugar application levels. Such constituent yields were modeled into constituent uptake distributions using simulations of nicotine uptake distributions generated on the basis of published nicotine biomonitoring data, which were multiplied by the constituent/nicotine ratios determined in the current analysis. These simulations revealed extensive overlaps for the constituent uptake distributions with and without sugar application. Moreover, the differences in smoke composition did not lead to relevant changes in the activity in in vitro or in vivo assays. The potential impact of using sugars as tobacco ingredients was further assessed in an indirect manner by comparing published data from markets with predominantly American-blend or Virginia-type (no added sugars) cigarettes. No relevant difference was found between these markets for smoking prevalence, intensity, some markers of dependence, nicotine uptake, or mortality from smoking-related lung cancer and chronic obstructive pulmonary disease. In conclusion, thorough examination of the data available suggests that the use of sugars as ingredients in cigarette tobacco does not increase the inherent risk and harm of cigarette smoking