Pub Date : 2024-09-03DOI: 10.1016/j.mtcomm.2024.110328
Qingsong Chen, Qing Li, Xiong Jiang, Xi Zhou, Xifan Ding, Maolin Zhao, Jijun Yang, Jun Yi, Chunhai Liu
The Cr and Cr/Mo coated Zr-4 alloys were deposited using magnetron sputtering deposition, and their microstructure evolution and interdiffusion behaviour were investigated. High-temperature diffusion tests revealed that the Cr-Zr eutectic reaction caused the performance of the Cr coating to drastically decline at 1330 °C, while the Cr/Mo coating was effective in preventing Cr-Zr interdiffusion even at 1400 ℃. Notably, the potential impact of the Mo-Zr diffusion layer formation on the service performance of the coatings should be considered. However, the Mo interlayer lost its blocking effect at 1500 ℃, led to severe deformation of the Zr-4 alloy. In addition, the diffusion mechanism was discussed.
{"title":"Microstructure evolution and interdiffusion behaviour of Cr/Mo coated Zr-4 alloys at 1330 °C-1500 °C","authors":"Qingsong Chen, Qing Li, Xiong Jiang, Xi Zhou, Xifan Ding, Maolin Zhao, Jijun Yang, Jun Yi, Chunhai Liu","doi":"10.1016/j.mtcomm.2024.110328","DOIUrl":"https://doi.org/10.1016/j.mtcomm.2024.110328","url":null,"abstract":"The Cr and Cr/Mo coated Zr-4 alloys were deposited using magnetron sputtering deposition, and their microstructure evolution and interdiffusion behaviour were investigated. High-temperature diffusion tests revealed that the Cr-Zr eutectic reaction caused the performance of the Cr coating to drastically decline at 1330 °C, while the Cr/Mo coating was effective in preventing Cr-Zr interdiffusion even at 1400 ℃. Notably, the potential impact of the Mo-Zr diffusion layer formation on the service performance of the coatings should be considered. However, the Mo interlayer lost its blocking effect at 1500 ℃, led to severe deformation of the Zr-4 alloy. In addition, the diffusion mechanism was discussed.","PeriodicalId":18477,"journal":{"name":"Materials Today Communications","volume":"11 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The effect of rivet length and sheet thickness on the cross-sectional formation and tensile-shear performance of self-piercing riveted joints in AA5754 aluminum alloy was examined through experimental investigation. The influence degree of joining parameters on the forming quality was analyzed. It was revealed that rivet length and sheet thickness are pivotal factors influencing the tensile-shear strength of the joint, culminating in the identification of four optimal riveting process schemes:Lhh、Lhh、Lhh and Lhh. A simulation model for self-piercing riveting was established, employing the GISSMO failure model and the modified Mohr-Coulomb (MMC) failure criteria to predict the damage and fracture of the aluminum alloy. A plethora of high-quality datasets depicting the cross-sections of the joints were derived from simulation analysis. Subsequently, the structure and hyperparameter determination method of traditional neural network prediction models were elucidated. By amalgamating the Aquila Optimization (AO) algorithm with the African Vultures Optimization Algorithm (AVOA), a hybrid optimization algorithm model known as MIC_AOAVOA was developed. This model effectively harnesses the strengths of various algorithms to augment search efficiency and optimization capabilities. Strategies for population initialization and adaptive weight adjustments were incorporated to enhance the algorithm's convergence velocity and the quality of solutions. The cauchy opposition-based learning (COBL) and fitness-distance balance (FDB) strategy further refined the composite algorithm, bolstering its global search capabilities and population diversity. Comparative analyses were performed with single algorithm models and traditional BP neural network models, with an in-depth examination of the MIC_AOAVOA_BP model's prediction outcomes. Comprehensive evaluations utilizing error statistics and composite evaluation indicators demonstrated that the model consistently achieved mean absolute percentage error (MAPE) values below 10 %, correlation coefficients (R²) exceeding 0.98, and stable mean squared error (MSE) values around 0.0002 across the prediction of three metrics. These results underscore the model's high precision and stability. Consequently, the proposed enhanced model offers a solution that is more stable, accurate, and robust for the prediction of forming quality in self-piercing riveted joints within engineering applications.
{"title":"High-fidelity prediction of forming quality for self-piercing riveted joints in aluminum alloy based on machine learning","authors":"Qingjun Wu, Yang Liu, Yilin Dai, Hao Guo, Yuqi Wang, Weimin Zhuang","doi":"10.1016/j.mtcomm.2024.110319","DOIUrl":"https://doi.org/10.1016/j.mtcomm.2024.110319","url":null,"abstract":"The effect of rivet length and sheet thickness on the cross-sectional formation and tensile-shear performance of self-piercing riveted joints in AA5754 aluminum alloy was examined through experimental investigation. The influence degree of joining parameters on the forming quality was analyzed. It was revealed that rivet length and sheet thickness are pivotal factors influencing the tensile-shear strength of the joint, culminating in the identification of four optimal riveting process schemes:Lhh、Lhh、Lhh and Lhh. A simulation model for self-piercing riveting was established, employing the GISSMO failure model and the modified Mohr-Coulomb (MMC) failure criteria to predict the damage and fracture of the aluminum alloy. A plethora of high-quality datasets depicting the cross-sections of the joints were derived from simulation analysis. Subsequently, the structure and hyperparameter determination method of traditional neural network prediction models were elucidated. By amalgamating the Aquila Optimization (AO) algorithm with the African Vultures Optimization Algorithm (AVOA), a hybrid optimization algorithm model known as MIC_AOAVOA was developed. This model effectively harnesses the strengths of various algorithms to augment search efficiency and optimization capabilities. Strategies for population initialization and adaptive weight adjustments were incorporated to enhance the algorithm's convergence velocity and the quality of solutions. The cauchy opposition-based learning (COBL) and fitness-distance balance (FDB) strategy further refined the composite algorithm, bolstering its global search capabilities and population diversity. Comparative analyses were performed with single algorithm models and traditional BP neural network models, with an in-depth examination of the MIC_AOAVOA_BP model's prediction outcomes. Comprehensive evaluations utilizing error statistics and composite evaluation indicators demonstrated that the model consistently achieved mean absolute percentage error (MAPE) values below 10 %, correlation coefficients (R²) exceeding 0.98, and stable mean squared error (MSE) values around 0.0002 across the prediction of three metrics. These results underscore the model's high precision and stability. Consequently, the proposed enhanced model offers a solution that is more stable, accurate, and robust for the prediction of forming quality in self-piercing riveted joints within engineering applications.","PeriodicalId":18477,"journal":{"name":"Materials Today Communications","volume":"11 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193545","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Electrospun nanofiber mats have aroused intensive attraction for the design and development of innovative wound dressing materials, due to their high specific surface area and porosity, great air permeability, and excellent extracellular matrix (ECM) imitativeness. In this study, piezoelectric poly (3-hydroxy butyric acid-co-3-hydroxy valeric acid) (PHBV) was electrospun into nanofibers, and two different concentrations of herbal extract, Salvia miltiorrhiza Bunge-Radix Puerariae herbal compound (SRHC), were loaded into PHBV nanofibers during the electrospinning process for constructing novel wound dressings with multiple functions. All the generated PHBV mats loading with or without SRHC were observed to be constructed with randomly oriented nanofibers with the diameters ranging from 200 nm to 900 nm, and the mean fiber diameter and mean pore size presented an increased trend with the addition of SRHC. The average fiber diameter and mean pore size of PHBV nanofiber mat loading with 5 % SRHC was determined to be 649.6±242.1 nm and 2.1±0.4 μm, respectively. The addition of SRHC was found to significantly enhance the surface hydrophilicity of as-generated PHBV nanofiber mats that was changed to be hydrophilic from hydrophobic, while maintain the high mechanical properties and piezoelectric properties originated from the main polymer, i.e., PHBV. Importantly, all the nanofiber mats exhibited great biological properties, and the nanofiber mat with high SRHC content was demonstrated to significantly improve the anti-oxidant and anti-inflammatory performances, as well as promote the adhesion and proliferation of human dermal fibroblasts. The present studies demonstrated pronounced advantages of SRHC-PHBV-5 % nanofiber mats to be used as potential wound dressing materials for the wound treatment.
{"title":"Electrospun herbal extract-loaded poly (3-hydroxy butyric acid-co-3-hydroxy valeric acid) nanofiber mats as potential wound dressing materials","authors":"Yafei Wang, Qi Meng, Yiran Li, Shaojuan Chen, Shaohua Wu","doi":"10.1016/j.mtcomm.2024.110300","DOIUrl":"https://doi.org/10.1016/j.mtcomm.2024.110300","url":null,"abstract":"Electrospun nanofiber mats have aroused intensive attraction for the design and development of innovative wound dressing materials, due to their high specific surface area and porosity, great air permeability, and excellent extracellular matrix (ECM) imitativeness. In this study, piezoelectric poly (3-hydroxy butyric acid-co-3-hydroxy valeric acid) (PHBV) was electrospun into nanofibers, and two different concentrations of herbal extract, Salvia miltiorrhiza Bunge-Radix Puerariae herbal compound (SRHC), were loaded into PHBV nanofibers during the electrospinning process for constructing novel wound dressings with multiple functions. All the generated PHBV mats loading with or without SRHC were observed to be constructed with randomly oriented nanofibers with the diameters ranging from 200 nm to 900 nm, and the mean fiber diameter and mean pore size presented an increased trend with the addition of SRHC. The average fiber diameter and mean pore size of PHBV nanofiber mat loading with 5 % SRHC was determined to be 649.6±242.1 nm and 2.1±0.4 μm, respectively. The addition of SRHC was found to significantly enhance the surface hydrophilicity of as-generated PHBV nanofiber mats that was changed to be hydrophilic from hydrophobic, while maintain the high mechanical properties and piezoelectric properties originated from the main polymer, i.e., PHBV. Importantly, all the nanofiber mats exhibited great biological properties, and the nanofiber mat with high SRHC content was demonstrated to significantly improve the anti-oxidant and anti-inflammatory performances, as well as promote the adhesion and proliferation of human dermal fibroblasts. The present studies demonstrated pronounced advantages of SRHC-PHBV-5 % nanofiber mats to be used as potential wound dressing materials for the wound treatment.","PeriodicalId":18477,"journal":{"name":"Materials Today Communications","volume":"11 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193551","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The metallization of graphite substrates is currently confronted by negative issues including insufficient adhesion and inherent instability. In an effort to surmount these challenges, a layer of conductive polypyrrole (PPy) film on a graphite surface is formed through simple polymerization, followed by an electroplating copper layer. The graphite enveloped by the PPy film, subjected to cyclic voltammetry (CV) and linear sweep voltammetry (LSV) analyses, demonstrates enhanced electrochemical activity and thus renders the more efficient electrodeposition of copper. Further investigation was conducted through orthogonal experiments to explore the optimal formulation of electroplating solutions containing popular additives including 3, 3′-dithiobis-1-propanesulfonic acid disodium salt (SPS), Janus Green B (JGB), and polyethylene glycol 8000 (PEG8000)., According to the optimal additive formulation, a dense copper layer with superior adhesion was electroplated on the graphite substrate employing PPy as an intermediate layer.
石墨基底的金属化目前面临着附着力不足和固有不稳定性等负面问题。为了克服这些难题，我们通过简单的聚合反应在石墨表面形成一层导电聚吡咯（PPy）薄膜，然后再电镀一层铜。在循环伏安法（CV）和线性扫描伏安法（LSV）分析中，被 PPy 膜包裹的石墨显示出更强的电化学活性，从而提高了铜的电沉积效率。通过正交实验进一步研究了含有常用添加剂（包括 3，3′-二硫代双-1-丙磺酸二钠盐（SPS）、Janus Green B（JGB）和聚乙二醇 8000（PEG8000））的电镀溶液的最佳配方。
{"title":"Investigation of the effect of electrodeposited Cu from graphite wrapped in polypyrrole film formed by chemical oxidation","authors":"Jiujuan Li, Genshuo Wen, Wei He, Yan Hong, Shouxu Wang, Guoyun Zhou, Chong Wang, Binbin Zhang, Haili Huang, Qinhua Li, Renhui Zhang","doi":"10.1016/j.mtcomm.2024.110322","DOIUrl":"https://doi.org/10.1016/j.mtcomm.2024.110322","url":null,"abstract":"The metallization of graphite substrates is currently confronted by negative issues including insufficient adhesion and inherent instability. In an effort to surmount these challenges, a layer of conductive polypyrrole (PPy) film on a graphite surface is formed through simple polymerization, followed by an electroplating copper layer. The graphite enveloped by the PPy film, subjected to cyclic voltammetry (CV) and linear sweep voltammetry (LSV) analyses, demonstrates enhanced electrochemical activity and thus renders the more efficient electrodeposition of copper. Further investigation was conducted through orthogonal experiments to explore the optimal formulation of electroplating solutions containing popular additives including 3, 3′-dithiobis-1-propanesulfonic acid disodium salt (SPS), Janus Green B (JGB), and polyethylene glycol 8000 (PEG8000)., According to the optimal additive formulation, a dense copper layer with superior adhesion was electroplated on the graphite substrate employing PPy as an intermediate layer.","PeriodicalId":18477,"journal":{"name":"Materials Today Communications","volume":"9 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-03DOI: 10.1016/j.mtcomm.2024.110307
He Zhang, Guo-Hua Zhang
In order to strengthen the overall properties of Mo-Cu alloy, Zr was added to Mo-Cu alloy to enhance the bond strength of Mo/Cu interface and form solid solution strengthening effect. The excellent properties of Mo-Cu-Zr blocks were attained through infiltrating Cu-Zr blocks containing various Zr contents into the Mo skeleton. Compared to the incoherent interface of Mo/Cu in Mo-Cu block, the addition of Zr changed its interface to the coherent interface of Mo-Zr/Cu-Zr. All Mo-Cu-Zr alloy blocks possessed high densification degrees (97.1 %∼98.4 %) to assure the excellent general properties. Besides, the formations of Mo-Zr and Cu-Zr solid solutions assured the block owned excellent mechanical strength. Especially, the addition of Zr purified the grain boundary through absorbing oxygen to produce ZrO which prevented the Mo-Zr grain growth. As increasing Zr amount from 0 to 4.73 wt%, the Mo-Zr (or Mo) grain size reduced from 5 to 4.0 μm. Mo-Cu sintered sample containing 2.40 wt% Zr possessed the highest tension strength of 494 MPa. Besides, since the finer grain size of Mo-Zr alloy, this block also owned the highest micro-hardness (250 HV) and bending strength (1626 MPa), respectively. But, the generations of Cu-Zr solid-solution and ZrO also damaged the electrical conductivities to a certain extent. Specifically, as the addition amount of zirconium increased from 0 to 2.40 wt%, the conductivity decreased from 42.67 % to 32.15 %IACS.
{"title":"Influence of Zr addition on the microstructure, mechanical and electrical properties of Mo-Cu alloy","authors":"He Zhang, Guo-Hua Zhang","doi":"10.1016/j.mtcomm.2024.110307","DOIUrl":"https://doi.org/10.1016/j.mtcomm.2024.110307","url":null,"abstract":"In order to strengthen the overall properties of Mo-Cu alloy, Zr was added to Mo-Cu alloy to enhance the bond strength of Mo/Cu interface and form solid solution strengthening effect. The excellent properties of Mo-Cu-Zr blocks were attained through infiltrating Cu-Zr blocks containing various Zr contents into the Mo skeleton. Compared to the incoherent interface of Mo/Cu in Mo-Cu block, the addition of Zr changed its interface to the coherent interface of Mo-Zr/Cu-Zr. All Mo-Cu-Zr alloy blocks possessed high densification degrees (97.1 %∼98.4 %) to assure the excellent general properties. Besides, the formations of Mo-Zr and Cu-Zr solid solutions assured the block owned excellent mechanical strength. Especially, the addition of Zr purified the grain boundary through absorbing oxygen to produce ZrO which prevented the Mo-Zr grain growth. As increasing Zr amount from 0 to 4.73 wt%, the Mo-Zr (or Mo) grain size reduced from 5 to 4.0 μm. Mo-Cu sintered sample containing 2.40 wt% Zr possessed the highest tension strength of 494 MPa. Besides, since the finer grain size of Mo-Zr alloy, this block also owned the highest micro-hardness (250 HV) and bending strength (1626 MPa), respectively. But, the generations of Cu-Zr solid-solution and ZrO also damaged the electrical conductivities to a certain extent. Specifically, as the addition amount of zirconium increased from 0 to 2.40 wt%, the conductivity decreased from 42.67 % to 32.15 %IACS.","PeriodicalId":18477,"journal":{"name":"Materials Today Communications","volume":"23 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193553","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-03DOI: 10.1016/j.mtcomm.2024.110301
Shunuo Bian, Wenqiang Lu, Lin Zhou, Tao Jin
Tumor is the main cause of death in human diseases, and the related research on tumor treatment is imminent. Phototherapy can achieve precise positioning and targeted removal of tumors in a non-invasive and minimally invasive manner, which has great potential for clinical application. Upconversion nanoparticles(UCNPs) can not only solve the problem of limited eradication of deep tissue tumors in current phototherapy, but also have the advantages of good stability, long life span and low biotoxicity. This article reviews the basic research status of phototherapy and the mechanism and application progress of UCNPs nanocomposites in phototherapy. This review focuses on the structure and composition regulation methods of UCNPs nanocomposites, which provides key points and solutions for the application design of UCNPs nanocomposites in phototherapy, and prospects the research and development in this field.
{"title":"Advances in upconversion nanomaterials for tumor phototherapy","authors":"Shunuo Bian, Wenqiang Lu, Lin Zhou, Tao Jin","doi":"10.1016/j.mtcomm.2024.110301","DOIUrl":"https://doi.org/10.1016/j.mtcomm.2024.110301","url":null,"abstract":"Tumor is the main cause of death in human diseases, and the related research on tumor treatment is imminent. Phototherapy can achieve precise positioning and targeted removal of tumors in a non-invasive and minimally invasive manner, which has great potential for clinical application. Upconversion nanoparticles(UCNPs) can not only solve the problem of limited eradication of deep tissue tumors in current phototherapy, but also have the advantages of good stability, long life span and low biotoxicity. This article reviews the basic research status of phototherapy and the mechanism and application progress of UCNPs nanocomposites in phototherapy. This review focuses on the structure and composition regulation methods of UCNPs nanocomposites, which provides key points and solutions for the application design of UCNPs nanocomposites in phototherapy, and prospects the research and development in this field.","PeriodicalId":18477,"journal":{"name":"Materials Today Communications","volume":"25 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The salt-frost damage characterization of multiple interfacial transition zones (ITZs) is one of the major concerns for further exploring the durability-related properties of recycled aggregate concrete (RAC) exposed to cold region. The actual service state of RAC structures is often coupled with multiple environments, leading to more complex freeze-thaw damage mechanisms in ITZs. This study adopted the simulant multiple ITZs of RAC specimens to investigate the damage evolution behavior of ITZs performance under the coupling actions of salt-frost cycles (SFT) and sustained compression loads. Effect of nano-silica (NS) and air-entraining agent (AE) on the salt-frost resistance strengthening for ITZs inside RAC was further explored. The apparent morphology and the relative dynamic elastic modulus (RDEM) of modified simulant multiple ITZs of RAC were measured to characterize the salt frost damage, and further the microstructural analysis including microhardness, laser scanning microscope (LSM) and SEM observation was conducted, aiming at revealing the salt-frost damage mechanisms of simulant modified ITZs inside RAC. The results indicate that the appropriate dosage of NS and AE could effectively reduce the salt-frost scaling of RAC by strengthening the internal microstructures. The RDEM of NS-modified RAC samples incorporating with AE was always higher than NS-modified RAC and non-modified RAC. After NS-modified, the minimum microhardness of old ITZs was increased by 10.2 % and the thickness was averagely reduced by about 10μm. The microhardness loss of modified RAC after SFT was relatively smaller. On the contrary, applying loading with higher compressive stress level markedly accelerates the salt-frost damage process of non-modified and modified ITZs. The results of SEM and LSM tests showed there is less salt-frost damage under sustained compression loads due to the denser microstructures of ITZs after synergistic modification by NS and AE. This is demonstrated by stronger bonding properties between original aggregate and old mortar and less elevation differences at old/new ITZs. Above all, this study explores the evolving trends of salt-frost damage and microstructure for simulant ITZs inside RAC under the coupling actions of sustained compression loads and SFT, which can provide some basis for the durability assessment of RAC structures exposed to cold region.
{"title":"Salt-frost damage characterization of simulant multiple ITZs in nano-silica modified recycled aggregate concrete","authors":"Hongrui Zhang, Haidong Xu, Jiuwen Bao, Ran Li, Qiang Song, Jianwei Sun, Ling Qin","doi":"10.1016/j.mtcomm.2024.110296","DOIUrl":"https://doi.org/10.1016/j.mtcomm.2024.110296","url":null,"abstract":"The salt-frost damage characterization of multiple interfacial transition zones (ITZs) is one of the major concerns for further exploring the durability-related properties of recycled aggregate concrete (RAC) exposed to cold region. The actual service state of RAC structures is often coupled with multiple environments, leading to more complex freeze-thaw damage mechanisms in ITZs. This study adopted the simulant multiple ITZs of RAC specimens to investigate the damage evolution behavior of ITZs performance under the coupling actions of salt-frost cycles (SFT) and sustained compression loads. Effect of nano-silica (NS) and air-entraining agent (AE) on the salt-frost resistance strengthening for ITZs inside RAC was further explored. The apparent morphology and the relative dynamic elastic modulus (RDEM) of modified simulant multiple ITZs of RAC were measured to characterize the salt frost damage, and further the microstructural analysis including microhardness, laser scanning microscope (LSM) and SEM observation was conducted, aiming at revealing the salt-frost damage mechanisms of simulant modified ITZs inside RAC. The results indicate that the appropriate dosage of NS and AE could effectively reduce the salt-frost scaling of RAC by strengthening the internal microstructures. The RDEM of NS-modified RAC samples incorporating with AE was always higher than NS-modified RAC and non-modified RAC. After NS-modified, the minimum microhardness of old ITZs was increased by 10.2 % and the thickness was averagely reduced by about 10μm. The microhardness loss of modified RAC after SFT was relatively smaller. On the contrary, applying loading with higher compressive stress level markedly accelerates the salt-frost damage process of non-modified and modified ITZs. The results of SEM and LSM tests showed there is less salt-frost damage under sustained compression loads due to the denser microstructures of ITZs after synergistic modification by NS and AE. This is demonstrated by stronger bonding properties between original aggregate and old mortar and less elevation differences at old/new ITZs. Above all, this study explores the evolving trends of salt-frost damage and microstructure for simulant ITZs inside RAC under the coupling actions of sustained compression loads and SFT, which can provide some basis for the durability assessment of RAC structures exposed to cold region.","PeriodicalId":18477,"journal":{"name":"Materials Today Communications","volume":"42 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142224916","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-03DOI: 10.1016/j.mtcomm.2024.110292
Qizhen He, Jibo Wang, Wenwei Song, Yuenian He, Xuejun Ren, Jing Guo, Qingxiang Yang
The refinement effect of the rare earth oxide LaO on γ-TiAl by first-principles method was investigated in this study. The mismatch between different low-index interfaces of LaO and γ-TiAl was calculated, and the interface with the smallest mismatch was selected to construct the LaO/γ-TiAl interface. The stability and electronic structure of the interface were assessed, and the efficacy of LaO as a heterogeneous nucleation core for γ-TiAl was analyzed. The results reveal that the LaO (100)/γ-TiAl(100) interface displays the smallest mismatch, which is 4.36 %. Four LaO (100)/γ-TiAl(100) interface models were constructed based on various surface terminations and stacking sequences. Among these models, the O-Al model exhibits the highest interfacial binding energy of 5.062 J/m, while the O-Ti model demonstrates the lowest interfacial energy of −3.300 J/m. The primary bond type in the interface models is ionic bonding. Therefore, from the geometric and energetic aspects of the interface structure, it can be inferred that LaO can act as a heterogeneous nucleation core for refining the γ-TiAl phase, with a preference for forming O-Ti type heterogeneous nucleation interfaces.
{"title":"Novel insights into heterogeneous nucleation interface properties between La2O3 and γ-TiAl: First-principles calculations","authors":"Qizhen He, Jibo Wang, Wenwei Song, Yuenian He, Xuejun Ren, Jing Guo, Qingxiang Yang","doi":"10.1016/j.mtcomm.2024.110292","DOIUrl":"https://doi.org/10.1016/j.mtcomm.2024.110292","url":null,"abstract":"The refinement effect of the rare earth oxide LaO on γ-TiAl by first-principles method was investigated in this study. The mismatch between different low-index interfaces of LaO and γ-TiAl was calculated, and the interface with the smallest mismatch was selected to construct the LaO/γ-TiAl interface. The stability and electronic structure of the interface were assessed, and the efficacy of LaO as a heterogeneous nucleation core for γ-TiAl was analyzed. The results reveal that the LaO (100)/γ-TiAl(100) interface displays the smallest mismatch, which is 4.36 %. Four LaO (100)/γ-TiAl(100) interface models were constructed based on various surface terminations and stacking sequences. Among these models, the O-Al model exhibits the highest interfacial binding energy of 5.062 J/m, while the O-Ti model demonstrates the lowest interfacial energy of −3.300 J/m. The primary bond type in the interface models is ionic bonding. Therefore, from the geometric and energetic aspects of the interface structure, it can be inferred that LaO can act as a heterogeneous nucleation core for refining the γ-TiAl phase, with a preference for forming O-Ti type heterogeneous nucleation interfaces.","PeriodicalId":18477,"journal":{"name":"Materials Today Communications","volume":"61 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193554","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-03DOI: 10.1016/j.mtcomm.2024.110267
Xi Fu, Jian Lin, Guangyao Liang, Wenhu Liao, Jiyuan Guo, Xiaowu Li, Liming Li
The photogalvanic effects (PGEs) in low-dimensional devices were thought to be an important mechanism to generate pure spin current which was a essential problem in spintronics. Herein, based on non-equilibrium Green’s function combined with density functional theory, we studied linear and elliptical spin dependent PGEs in the photodetector based on the penta-PdN monolayer at zero bias. Due to spin-orbit coupling originating from the heavy metal atoms Pd and low symmetry of C for the pristine case and C for the defect cases, the penta-PdN photodetector at pristine, vacancy and substitution-doping situations can produce robust spin dependent PGEs, and the import of defects were able to strengthen the linear and elliptical PGEs, respectively. More importantly, on account of enormous splitting of the DOS for the pristine, Pd-vacancy, N-vacancy and NN-vacancy cases, spin up and spin down photocurrents accordingly formed spin splitting, which eventually led to full spin polarization and then pure spin currents in the penta-PdN photodetector. PdSe monolayer has been compounded in experiments, so structurally similar penta-PdN monolayer possesses highly possible to be prepared. Therefore, if the penta-PdN photodetector can be successful assembled, the spin-generator will be reality, even no need to be doped because the pristine penta-PdN photodetector can give rise to pure spin currents. In addtion, the penta-PdN photodetector at different situations are highly polarization sensitive. In conclude, our work suggested great potential applications of the penta-PdN monolayer on PGE-driven low energy-consumption photodetectors and spin-generators in optoelectronics and spintronics.
低维器件中的光电效应（PGEs）被认为是产生纯自旋电流的重要机制，而这正是自旋电子学中的一个基本问题。在此，我们基于非平衡格林函数和密度泛函理论，研究了零偏压下基于五钯单层的光电探测器中的线性和椭圆自旋相关 PGEs。由于重金属原子 Pd 的自旋轨道耦合以及原始情况下 C 的低对称性和缺陷情况下 C 的低对称性，五钯氮光电探测器在原始、空位和置换掺杂情况下都能产生稳健的自旋相关 PGE，而缺陷的输入则能分别加强线性和椭圆 PGE。更重要的是，由于原始、Pd-空位、N-空位和 NN-空位情况下 DOS 的巨大分裂，自旋上行和自旋下行光电流也相应地形成了自旋分裂，最终在五钯硒光电探测器中形成了完全的自旋极化和纯自旋电流。钯硒单层已在实验中复合，因此极有可能制备出结构类似的五钯萘单层。因此，如果五钯氮光电探测器能够成功组装，自旋发生器将成为现实，甚至无需掺杂，因为原始的五钯氮光电探测器可以产生纯净的自旋电流。此外，五氧化钯光电探测器在不同情况下都具有高度的偏振敏感性。总之，我们的工作表明，五钯单层在 PGE 驱动的低能耗光电探测器和自旋发电机上的应用潜力巨大，可用于光电子学和自旋电子学领域。
{"title":"Full spin polarization and pure spin current produced by the photogalvanic effect in penta-PdN2 photodetector","authors":"Xi Fu, Jian Lin, Guangyao Liang, Wenhu Liao, Jiyuan Guo, Xiaowu Li, Liming Li","doi":"10.1016/j.mtcomm.2024.110267","DOIUrl":"https://doi.org/10.1016/j.mtcomm.2024.110267","url":null,"abstract":"The photogalvanic effects (PGEs) in low-dimensional devices were thought to be an important mechanism to generate pure spin current which was a essential problem in spintronics. Herein, based on non-equilibrium Green’s function combined with density functional theory, we studied linear and elliptical spin dependent PGEs in the photodetector based on the penta-PdN monolayer at zero bias. Due to spin-orbit coupling originating from the heavy metal atoms Pd and low symmetry of C for the pristine case and C for the defect cases, the penta-PdN photodetector at pristine, vacancy and substitution-doping situations can produce robust spin dependent PGEs, and the import of defects were able to strengthen the linear and elliptical PGEs, respectively. More importantly, on account of enormous splitting of the DOS for the pristine, Pd-vacancy, N-vacancy and NN-vacancy cases, spin up and spin down photocurrents accordingly formed spin splitting, which eventually led to full spin polarization and then pure spin currents in the penta-PdN photodetector. PdSe monolayer has been compounded in experiments, so structurally similar penta-PdN monolayer possesses highly possible to be prepared. Therefore, if the penta-PdN photodetector can be successful assembled, the spin-generator will be reality, even no need to be doped because the pristine penta-PdN photodetector can give rise to pure spin currents. In addtion, the penta-PdN photodetector at different situations are highly polarization sensitive. In conclude, our work suggested great potential applications of the penta-PdN monolayer on PGE-driven low energy-consumption photodetectors and spin-generators in optoelectronics and spintronics.","PeriodicalId":18477,"journal":{"name":"Materials Today Communications","volume":"9 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193555","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-03DOI: 10.1016/j.mtcomm.2024.110257
Qiufeng Jiang, Peng Tang, Hao Jiang
The presence of long acicular Fe-rich intermetallic compound phases in recycled Al-Si alloys significantly affects the mechanical properties of the alloy. In-situ formed ceramic particles, serving as reinforcing phases, can optimize the material's performance while maintaining thermodynamic stability. This study utilized the in-situ preparation method via a stir casting process to produce TiC/Al-Si-Fe composite materials, investigating the impact of in-situ TiC particles on the mechanical properties and microstructural evolution of the Al-12Si-1.7Fe cast alloy. The potential for TiC formation was assessed based on the principles of chemical reaction thermodynamics. The results indicate that the addition of Ti and C refined the microstructure and led to a more uniform phase distribution. Some Fe-rich phases transformed from long acicular structures to fishbone-like structures, effectively alleviating stress concentration. Furthermore, the formation of a small amount of AlTi phase, in conjunction with the hard TiC reinforcing particles, significantly reduced the average coefficient of friction from 0.91 to 0.6, shifting the wear mode from a complex pattern to one dominated by abrasive wear. However, the presence of incompletely reacted carbon particles and the segregated (Al,Si)Ti phase negatively impacted the susceptibility to brittle failure of the matrix. This in-situ ceramic particle preparation method provides valuable guidance for the study of wear resistance, phase transformation, and strengthening mechanisms in recycled Fe-rich Al-Si alloys.
{"title":"Synergistic effect of in-situ TiC particles synthesis on microstructure and mechanical properties of Fe-rich eutectic Al-Si alloy","authors":"Qiufeng Jiang, Peng Tang, Hao Jiang","doi":"10.1016/j.mtcomm.2024.110257","DOIUrl":"https://doi.org/10.1016/j.mtcomm.2024.110257","url":null,"abstract":"The presence of long acicular Fe-rich intermetallic compound phases in recycled Al-Si alloys significantly affects the mechanical properties of the alloy. In-situ formed ceramic particles, serving as reinforcing phases, can optimize the material's performance while maintaining thermodynamic stability. This study utilized the in-situ preparation method via a stir casting process to produce TiC/Al-Si-Fe composite materials, investigating the impact of in-situ TiC particles on the mechanical properties and microstructural evolution of the Al-12Si-1.7Fe cast alloy. The potential for TiC formation was assessed based on the principles of chemical reaction thermodynamics. The results indicate that the addition of Ti and C refined the microstructure and led to a more uniform phase distribution. Some Fe-rich phases transformed from long acicular structures to fishbone-like structures, effectively alleviating stress concentration. Furthermore, the formation of a small amount of AlTi phase, in conjunction with the hard TiC reinforcing particles, significantly reduced the average coefficient of friction from 0.91 to 0.6, shifting the wear mode from a complex pattern to one dominated by abrasive wear. However, the presence of incompletely reacted carbon particles and the segregated (Al,Si)Ti phase negatively impacted the susceptibility to brittle failure of the matrix. This in-situ ceramic particle preparation method provides valuable guidance for the study of wear resistance, phase transformation, and strengthening mechanisms in recycled Fe-rich Al-Si alloys.","PeriodicalId":18477,"journal":{"name":"Materials Today Communications","volume":"2012 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193561","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：