Pub Date : 2025-12-26DOI: 10.1016/j.powtec.2025.122066
Zelin Zhang , Hang Wan , Lei Wang , Yuyao Guo , Jianhua Cao , Xuhui Xia
The screening performance of electromagnetic linear vibrating screens is significantly influenced by the coordinated regulation of excitation frequency and amplitude across multiple actuators. In this study, a Discrete Element Method (DEM) and Multibody Flexible Body Dynamics (DEM-MFBD) coupled simulation framework was developed to perform multi-objective optimization of screening parameters, with screening efficiency (SE) and screen surface load (SSL) as dual targets. First, a DEM-MFBD co-simulation model was established to investigate screen surface dynamics and particle motion under variable frequency and amplitude conditions. Subsequently, quantitative evaluation indices for SE and SSL were defined. The effects of key operating parameters—vibration frequency, amplitude, and direction angle—on screening performance were systematically analyzed through numerical simulation experiments. Finally, based on the simulation data, the non-dominated sorting genetic algorithm (NSGA-II) was employed to optimize the screening parameters, resulting in a collaborative multi-objective screening strategy. The results show that the optimized SE reaches 90.1 %, and the SSL is 39.6 N.
{"title":"Collaborative optimization of screening efficiency and screen surface load in electromagnetic linear vibrating screen under variable frequency and amplitude","authors":"Zelin Zhang , Hang Wan , Lei Wang , Yuyao Guo , Jianhua Cao , Xuhui Xia","doi":"10.1016/j.powtec.2025.122066","DOIUrl":"10.1016/j.powtec.2025.122066","url":null,"abstract":"<div><div>The screening performance of electromagnetic linear vibrating screens is significantly influenced by the coordinated regulation of excitation frequency and amplitude across multiple actuators. In this study, a Discrete Element Method (DEM) and Multibody Flexible Body Dynamics (DEM-MFBD) coupled simulation framework was developed to perform multi-objective optimization of screening parameters, with screening efficiency (SE) and screen surface load (SSL) as dual targets. First, a DEM-MFBD co-simulation model was established to investigate screen surface dynamics and particle motion under variable frequency and amplitude conditions. Subsequently, quantitative evaluation indices for SE and SSL were defined. The effects of key operating parameters—vibration frequency, amplitude, and direction angle—on screening performance were systematically analyzed through numerical simulation experiments. Finally, based on the simulation data, the non-dominated sorting genetic algorithm (NSGA-II) was employed to optimize the screening parameters, resulting in a collaborative multi-objective screening strategy. The results show that the optimized SE reaches 90.1 %, and the SSL is 39.6 N.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"471 ","pages":"Article 122066"},"PeriodicalIF":4.6,"publicationDate":"2025-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145882461","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-26DOI: 10.1016/j.powtec.2025.122063
Alice Parkes , Joke Janssens , Geert Van Nyen , Marcin Marczak , Maarten Knol , Giorgio Orlandin , Emmet O'Reilly , Mukul Ashtikar , Chris Galle , Sune K. Andersen , Noor Al-Rifai
Formulating suspensions that will remain stable throughout their shelf-life without changes in particle size is critical for pharmaceutical products. Suspension instability impacts the final product quality, hence methods to enhance the stability of pharmaceutical suspensions over their storage period at room temperature are sought after. In this investigation, two drying techniques – electrostatic spray drying (ESD) and conventional spray drying (SD) – are evaluated as potential methods to enhance the stability of two pharmaceutical suspensions: an indomethacin suspension and an API D suspension, throughout their shelf-life, in powder form, at room temperature. This may provide an alternative pathway to stabilising suspensions for reconstitution, potentially bringing down cost of goods due to improved stabilisation at room temperature and thereby eliminating the need for cold storage. Process optimisations were performed and the reconstituted suspensions were analysed to determine whether their properties were retained and comparable to the original suspensions. The results showed that the optimised ESD and SD parameters produced samples with a moisture content of less than 0.4 % w/w and the purity of the optimised samples from both techniques was within 95–105 % w/w. Upon reconstitution, both SD and ESD suspensions had comparable PSD, to each other, and to the original milled suspension. Furthermore, this investigation showed that ESD and SD were successful in producing spray dried powder of two pharmaceutical suspensions, which remained stable for 1 month at 25 °C/60 % RH, and could be resuspended whilst retaining the original suspension properties.
{"title":"Particle engineering to stabilise microsuspensions via electrostatic and conventional spray drying","authors":"Alice Parkes , Joke Janssens , Geert Van Nyen , Marcin Marczak , Maarten Knol , Giorgio Orlandin , Emmet O'Reilly , Mukul Ashtikar , Chris Galle , Sune K. Andersen , Noor Al-Rifai","doi":"10.1016/j.powtec.2025.122063","DOIUrl":"10.1016/j.powtec.2025.122063","url":null,"abstract":"<div><div>Formulating suspensions that will remain stable throughout their shelf-life without changes in particle size is critical for pharmaceutical products. Suspension instability impacts the final product quality, hence methods to enhance the stability of pharmaceutical suspensions over their storage period at room temperature are sought after. In this investigation, two drying techniques – electrostatic spray drying (ESD) and conventional spray drying (SD) – are evaluated as potential methods to enhance the stability of two pharmaceutical suspensions: an indomethacin suspension and an API D suspension, throughout their shelf-life, in powder form, at room temperature. This may provide an alternative pathway to stabilising suspensions for reconstitution, potentially bringing down cost of goods due to improved stabilisation at room temperature and thereby eliminating the need for cold storage. Process optimisations were performed and the reconstituted suspensions were analysed to determine whether their properties were retained and comparable to the original suspensions. The results showed that the optimised ESD and SD parameters produced samples with a moisture content of less than 0.4 % <em>w</em>/w and the purity of the optimised samples from both techniques was within 95–105 % w/w. Upon reconstitution, both SD and ESD suspensions had comparable PSD, to each other, and to the original milled suspension. Furthermore, this investigation showed that ESD and SD were successful in producing spray dried powder of two pharmaceutical suspensions, which remained stable for 1 month at 25 °C/60 % RH, and could be resuspended whilst retaining the original suspension properties.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"471 ","pages":"Article 122063"},"PeriodicalIF":4.6,"publicationDate":"2025-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145922558","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-26DOI: 10.1016/j.powtec.2025.122042
Andreas Mayr , Yunhao Liang , Lucas Hille , Rüdiger Daub
The global shift towards electromobility drives the demand for high-energy-density lithium-ion batteries. Gaining an in-depth knowledge of battery production steps is crucial to meet this demand. Electrodes, a key component in lithium-ion batteries, consist of a multi-material system coated on a metallic current collector foil. Calendering affects mechanical and electrochemical properties by compacting the electrodes and defining the volumetric energy density. The strive for higher energy densities and the associated high compaction rates during calendering lead to an increase in electrode deformations. The coated particles are pressed into the current collector foil during compaction, influencing the electrode's electrical and mechanical properties at the interface. A holistic understanding of particle behavior during compaction is essential for producing high-quality electrodes. In this work, an automated, model-based approach is adapted for the process analysis to determine the calendering-induced particle indentations and the resulting contact area for lithium-ion battery cathodes. The methodology presented in this study enables the quantification of the contact area and the associated calendering-induced microstructural deformations of the current collector foil. A strong correlation was identified between the contact area and the characteristic values for the electrical resistance and adhesion strength at the interface between the coating and the current collector foil. The particle indentations are dependent on the mechanical specification of the current collector foil used, as a softer aluminum foil leads to a larger contact area.
{"title":"A methodology for evaluating electrode interface quality through contact area analysis of calendering-induced particle indentations","authors":"Andreas Mayr , Yunhao Liang , Lucas Hille , Rüdiger Daub","doi":"10.1016/j.powtec.2025.122042","DOIUrl":"10.1016/j.powtec.2025.122042","url":null,"abstract":"<div><div>The global shift towards electromobility drives the demand for high-energy-density lithium-ion batteries. Gaining an in-depth knowledge of battery production steps is crucial to meet this demand. Electrodes, a key component in lithium-ion batteries, consist of a multi-material system coated on a metallic current collector foil. Calendering affects mechanical and electrochemical properties by compacting the electrodes and defining the volumetric energy density. The strive for higher energy densities and the associated high compaction rates during calendering lead to an increase in electrode deformations. The coated particles are pressed into the current collector foil during compaction, influencing the electrode's electrical and mechanical properties at the interface. A holistic understanding of particle behavior during compaction is essential for producing high-quality electrodes. In this work, an automated, model-based approach is adapted for the process analysis to determine the calendering-induced particle indentations and the resulting contact area for lithium-ion battery cathodes. The methodology presented in this study enables the quantification of the contact area and the associated calendering-induced microstructural deformations of the current collector foil. A strong correlation was identified between the contact area and the characteristic values for the electrical resistance and adhesion strength at the interface between the coating and the current collector foil. The particle indentations are dependent on the mechanical specification of the current collector foil used, as a softer aluminum foil leads to a larger contact area.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"472 ","pages":"Article 122042"},"PeriodicalIF":4.6,"publicationDate":"2025-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146035751","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-25DOI: 10.1016/j.powtec.2025.122073
Zhuang Cheng , Bin He , Dongsheng Xu , Xiaochun Fan , Hong Shen
Seepage erosion is a frequent cause of failure in earth dams, embankments and foundations. In practice, soils exhibit broad particle-size distributions and highly irregular grain shapes, making their response to seepage erosion highly complex. In this paper, gap-graded soils with spherical, cubic, tetrahedral or ellipsoidal coarse grains subjected to seepage erosion were investigated using a CFD-DEM model. Digital images of the specimen pore spaces extracted at successive stages revealed that every specimen lost pore-space complexity and connectivity: fractal dimension fell and Euler number rose. Specimens containing coarse particles with lower sphericity or aspect ratio intensified fines loss, as their reduced surface area and simpler pore topology offered less resistance to fine-particle transport. Additionally, specimens with spherical coarse grains experienced growth in large pores and shrinkage in small pores, whereas those with irregularly shaped coarse grains produced the opposite trend. The study demonstrates that particle shape critically governs the seepage-erosion behaviour of gap-graded soils, dictating pore-network evolution and the magnitude of internal erosion.
{"title":"A CFD-DEM study on seepage erosion and pore-structure evolution in gap-graded soils with irregular grain shapes","authors":"Zhuang Cheng , Bin He , Dongsheng Xu , Xiaochun Fan , Hong Shen","doi":"10.1016/j.powtec.2025.122073","DOIUrl":"10.1016/j.powtec.2025.122073","url":null,"abstract":"<div><div>Seepage erosion is a frequent cause of failure in earth dams, embankments and foundations. In practice, soils exhibit broad particle-size distributions and highly irregular grain shapes, making their response to seepage erosion highly complex. In this paper, gap-graded soils with spherical, cubic, tetrahedral or ellipsoidal coarse grains subjected to seepage erosion were investigated using a CFD-DEM model. Digital images of the specimen pore spaces extracted at successive stages revealed that every specimen lost pore-space complexity and connectivity: fractal dimension fell and Euler number rose. Specimens containing coarse particles with lower sphericity or aspect ratio intensified fines loss, as their reduced surface area and simpler pore topology offered less resistance to fine-particle transport. Additionally, specimens with spherical coarse grains experienced growth in large pores and shrinkage in small pores, whereas those with irregularly shaped coarse grains produced the opposite trend. The study demonstrates that particle shape critically governs the seepage-erosion behaviour of gap-graded soils, dictating pore-network evolution and the magnitude of internal erosion.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"471 ","pages":"Article 122073"},"PeriodicalIF":4.6,"publicationDate":"2025-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145882530","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-25DOI: 10.1016/j.powtec.2025.122072
Chungong Gao , Shunjun Hong , Zihai Yang , Xiaozhou Hu , Yuqi Han , Rui Xu , Xingpeng Wang
The wear mechanism in centrifugal pumps under high-concentration, fine-grained sediment conditions remains a critical challenge. This study addresses this gap by investigating an agricultural centrifugal pump (Q = 25 m3/h, n = 2900 r/min) across a computational domain comprising the inlet section, impeller, volute, and outlet section. A high-fidelity Dense Discrete Phase Model (DDPM)-Oka coupled model, integrated with the Shear Stress Transport (SST) k-ω turbulence model and the Omega-Q criterion, is employed to establish a clear mechanistic link between meso-scale flow structures and micro-scale particle behavior. The effects of rotational speed (0.75n, 1.0n, and 1.15n) are examined for a specific fine-grained particle size of 0.08 mm at a high sediment mass concentration of 18 %. Key findings reveal two distinct, operating-condition-dependent wear mechanisms: at the low-speed condition (0.75n), internal stall vortices act as particle traps, leading to abrasive wear dominated by sliding and accumulation; whereas at the high-speed condition (1.15n), intense rotor-stator interaction at the volute tongue induces high-energy turbulence, shifting the dominant mode to impact erosion. This work offers new physical insights into the interplay between particle dynamics and turbulent structures, providing a theoretical basis for optimizing pump longevity in sediment-rich environments.
高浓度、细粒泥沙条件下离心泵的磨损机理仍然是一个严峻的挑战。本研究通过研究农业离心泵（Q = 25 m3/h, n = 2900 r/min）来解决这一差距，该计算域包括进口部分，叶轮，蜗壳和出口部分。采用高保真密度离散相模型(DDPM)-Oka耦合模型，结合剪切应力输移（SST） k-ω湍流模型和Omega-Q准则，在中尺度流动结构和微观尺度颗粒行为之间建立了清晰的机制联系。研究了转速（0.75n、1.0n和1.15n）对特定细粒粒径为0.08 mm、高沉积物质量浓度为18%时的影响。主要研究结果揭示了两种不同的、依赖于工况的磨损机制：在低速工况下（0.75n），内部失速涡作为颗粒陷阱，导致以滑动和堆积为主的磨粒磨损；而在高速条件下（1.15n），蜗壳舌处强烈的动静相互作用会引起高能湍流，将主要模式转变为冲击侵蚀。这项工作为颗粒动力学和湍流结构之间的相互作用提供了新的物理见解，为在富含沉积物的环境中优化泵的寿命提供了理论基础。
{"title":"Particle transport and erosion mechanisms in a high-concentration slurry pump:A DDPM-Oka coupled investigation","authors":"Chungong Gao , Shunjun Hong , Zihai Yang , Xiaozhou Hu , Yuqi Han , Rui Xu , Xingpeng Wang","doi":"10.1016/j.powtec.2025.122072","DOIUrl":"10.1016/j.powtec.2025.122072","url":null,"abstract":"<div><div>The wear mechanism in centrifugal pumps under high-concentration, fine-grained sediment conditions remains a critical challenge. This study addresses this gap by investigating an agricultural centrifugal pump (Q = 25 m<sup>3</sup>/h, <em>n</em> = 2900 r/min) across a computational domain comprising the inlet section, impeller, volute, and outlet section. A high-fidelity Dense Discrete Phase Model (DDPM)-Oka coupled model, integrated with the Shear Stress Transport (SST) k-ω turbulence model and the Omega-Q criterion, is employed to establish a clear mechanistic link between meso-scale flow structures and micro-scale particle behavior. The effects of rotational speed (0.75n, 1.0n, and 1.15n) are examined for a specific fine-grained particle size of 0.08 mm at a high sediment mass concentration of 18 %. Key findings reveal two distinct, operating-condition-dependent wear mechanisms: at the low-speed condition (0.75n), internal stall vortices act as particle traps, leading to abrasive wear dominated by sliding and accumulation; whereas at the high-speed condition (1.15n), intense rotor-stator interaction at the volute tongue induces high-energy turbulence, shifting the dominant mode to impact erosion. This work offers new physical insights into the interplay between particle dynamics and turbulent structures, providing a theoretical basis for optimizing pump longevity in sediment-rich environments.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"471 ","pages":"Article 122072"},"PeriodicalIF":4.6,"publicationDate":"2025-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145922560","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-25DOI: 10.1016/j.powtec.2025.122067
Majid Moghaddam, Marcello Papini
Abrasive slurry jets can be used as cost-effective and versatile means for the controlled depth micro-milling of planar areas. Erosion-resistant masks can be incorporated in the process to mill complex patterns with enhanced precision. However, because of the unpredictable interaction between the jet and mask, an undesirable erosion and mask under-etch can occur in the machined pocket near the mask edges. This paper investigates how mask configuration affects this interaction, and presents a novel method using non-contact shadow masks that virtually eliminates the undesirable effects. A high-pressure slurry jet setup was used to mill square pockets in Al 6061-T6 using both contact and shadow masks made from SS304 of varying thickness and in various configurations. Experimentally validated computational fluid dynamics (CFD) coupled with Lagrangian particle tracing was used to predict the severity of the undesirable erosion as well as its underlying mechanisms in the various scenarios. For contact masks, thicker masks led to more undesirable erosion because of the greater possibility for the flow to separate and recirculate, resulting in a locally high abrasive mass flux near the mask edge. The undesirable effects occurred to a lesser degree when shadow masks were used because there was no such flow separation. Although the flow streamlines compressed near the shadow mask edge yielding a locally high erosive efficacy, this could be mitigated by using a high mask to surface standoff that allowed the jet to spread before striking the surface. With the shadow mask in this configuration, the undesirable erosion was virtually eliminated, allowing for the micro-fabrication of planar areas at a far more uniform depth and reduced under-etch than when using contact masks.
{"title":"Shadow and contact masks for abrasive slurry jet micro-machining of planar areas with uniform depth","authors":"Majid Moghaddam, Marcello Papini","doi":"10.1016/j.powtec.2025.122067","DOIUrl":"10.1016/j.powtec.2025.122067","url":null,"abstract":"<div><div>Abrasive slurry jets can be used as cost-effective and versatile means for the controlled depth micro-milling of planar areas. Erosion-resistant masks can be incorporated in the process to mill complex patterns with enhanced precision. However, because of the unpredictable interaction between the jet and mask, an undesirable erosion and mask under-etch can occur in the machined pocket near the mask edges. This paper investigates how mask configuration affects this interaction, and presents a novel method using non-contact shadow masks that virtually eliminates the undesirable effects. A high-pressure slurry jet setup was used to mill square pockets in <em>Al</em> 6061-T6 using both contact and shadow masks made from SS304 of varying thickness and in various configurations. Experimentally validated computational fluid dynamics (CFD) coupled with Lagrangian particle tracing was used to predict the severity of the undesirable erosion as well as its underlying mechanisms in the various scenarios. For contact masks, thicker masks led to more undesirable erosion because of the greater possibility for the flow to separate and recirculate, resulting in a locally high abrasive mass flux near the mask edge. The undesirable effects occurred to a lesser degree when shadow masks were used because there was no such flow separation. Although the flow streamlines compressed near the shadow mask edge yielding a locally high erosive efficacy, this could be mitigated by using a high mask to surface standoff that allowed the jet to spread before striking the surface. With the shadow mask in this configuration, the undesirable erosion was virtually eliminated, allowing for the micro-fabrication of planar areas at a far more uniform depth and reduced under-etch than when using contact masks.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"471 ","pages":"Article 122067"},"PeriodicalIF":4.6,"publicationDate":"2025-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145839711","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-24DOI: 10.1016/j.powtec.2025.122068
Xingyu Zhang , Longzao Zhou , Fengshun Wu , Hengrui Li , Liguo Ding , Kewei Li , Xuemin Li
In the field of SiC power device packaging, copper sintering technique is thought to have a wide range of application potential due to its excellent electrical/thermal conductivity and high temperature reliability characteristics. Micron-nano composite copper sintering effectively balances the cost benefits of micron copper with the superior sintering ability of nano copper, providing an optimal solution for electronic packaging. Therefore, this work used micron-nano composite copper sintering for die bonding in power devices. So far, there are few studies on the process parameters of micron-nano composite copper sintering for SiC device packaging, and the research on the fracture mechanism of the joint interface is insufficient. In this work, micron-nano composite copper paste was employed to interconnect SiC chips and bare copper substrates. The influence of process parameters on the shear strength of the sintered layer was systematically investigated, accompanied by analysis of the fracture morphology. Furthermore, the underlying fracture mechanisms and interfacial interconnection behavior were elucidated through molecular dynamics (MD) simulations. According to the test results, shear strength rises as sintering temperature, sintering duration, and sintering pressure increase. The optimal process parameters were determined to be 280 °C, 10 MPa, and 7 min, under which the shear strength reached 42.29 MPa. These findings provide a basis for the preparation of low cost, high reliability micron-nano composite copper joints.
{"title":"Research on optimization of process parameters and interface interconnection mechanism of micron-nano composite copper sintering for power device packaging","authors":"Xingyu Zhang , Longzao Zhou , Fengshun Wu , Hengrui Li , Liguo Ding , Kewei Li , Xuemin Li","doi":"10.1016/j.powtec.2025.122068","DOIUrl":"10.1016/j.powtec.2025.122068","url":null,"abstract":"<div><div>In the field of SiC power device packaging, copper sintering technique is thought to have a wide range of application potential due to its excellent electrical/thermal conductivity and high temperature reliability characteristics. Micron-nano composite copper sintering effectively balances the cost benefits of micron copper with the superior sintering ability of nano copper, providing an optimal solution for electronic packaging. Therefore, this work used micron-nano composite copper sintering for die bonding in power devices. So far, there are few studies on the process parameters of micron-nano composite copper sintering for SiC device packaging, and the research on the fracture mechanism of the joint interface is insufficient. In this work, micron-nano composite copper paste was employed to interconnect SiC chips and bare copper substrates. The influence of process parameters on the shear strength of the sintered layer was systematically investigated, accompanied by analysis of the fracture morphology. Furthermore, the underlying fracture mechanisms and interfacial interconnection behavior were elucidated through molecular dynamics (MD) simulations. According to the test results, shear strength rises as sintering temperature, sintering duration, and sintering pressure increase. The optimal process parameters were determined to be 280 °C, 10 MPa, and 7 min, under which the shear strength reached 42.29 MPa. These findings provide a basis for the preparation of low cost, high reliability micron-nano composite copper joints.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"471 ","pages":"Article 122068"},"PeriodicalIF":4.6,"publicationDate":"2025-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145882480","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-24DOI: 10.1016/j.powtec.2025.122070
Xumin Sun , Rui Zhang , Xiujuan Li , Meng Zou , Hua Zhang
To accurately simulate the dynamic interaction between excavation tools and lunar highland simulant, this study combined physical and numerical experiments to calibrate the discrete element parameters for the lunar highland simulant (JLU-H). Since the mechanical response of compacted lunar simulants significantly differs from that of loose media, conventional angle of repose or penetration tests are inadequate for characterizing its dynamic behavior. A dynamic-static calibration strategy was proposed: intrinsic parameters and excavation force were obtained through physical experiments, a particle system was established based on the Hertz-Mindlin with Bonding model, and parameter screening and optimization were achieved using Plackett-Burman, steepest ascent, and Box-Behnken experimental designs. The model was validated through excavation and cone penetration tests. The relative error between the simulation and experimental results was less than 5 %, which significantly enhanced the model's adaptability and predictive accuracy for in-situ compacted lunar soil simulant conditions. This study provides reliable support for the design of lunar excavation machinery and research on tool-soil interaction under low-gravity conditions.
为了准确模拟挖掘工具与月球高原模拟物之间的动态相互作用，本研究将物理实验与数值实验相结合，对月球高原模拟物（JLU-H）的离散元参数进行了标定。由于压实月球模拟物的力学响应与松散介质的力学响应明显不同，传统的休止角或穿透试验不足以表征其动态行为。提出了一种动静态标定策略：通过物理实验获得内部参数和开挖力，基于Hertz-Mindlin with Bonding模型建立粒子体系，采用Plackett-Burman、最陡爬坡和Box-Behnken实验设计进行参数筛选和优化。通过开挖试验和锥入试验对模型进行了验证。模拟结果与实验结果的相对误差小于5%，显著提高了模型对原位压实月壤模拟条件的适应性和预测精度。该研究为低重力条件下月球挖掘机械的设计和工具-土壤相互作用研究提供了可靠的支撑。
{"title":"Calibration of simulation parameters for in-situ excavation of lunar highland simulant","authors":"Xumin Sun , Rui Zhang , Xiujuan Li , Meng Zou , Hua Zhang","doi":"10.1016/j.powtec.2025.122070","DOIUrl":"10.1016/j.powtec.2025.122070","url":null,"abstract":"<div><div>To accurately simulate the dynamic interaction between excavation tools and lunar highland simulant, this study combined physical and numerical experiments to calibrate the discrete element parameters for the lunar highland simulant (JLU-H). Since the mechanical response of compacted lunar simulants significantly differs from that of loose media, conventional angle of repose or penetration tests are inadequate for characterizing its dynamic behavior. A dynamic-static calibration strategy was proposed: intrinsic parameters and excavation force were obtained through physical experiments, a particle system was established based on the Hertz-Mindlin with Bonding model, and parameter screening and optimization were achieved using Plackett-Burman, steepest ascent, and Box-Behnken experimental designs. The model was validated through excavation and cone penetration tests. The relative error between the simulation and experimental results was less than 5 %, which significantly enhanced the model's adaptability and predictive accuracy for in-situ compacted lunar soil simulant conditions. This study provides reliable support for the design of lunar excavation machinery and research on tool-soil interaction under low-gravity conditions.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"471 ","pages":"Article 122070"},"PeriodicalIF":4.6,"publicationDate":"2025-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145882527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fluid-driven particle transport represents a common phenomenon in subsurface flow. However, the pore-scale controls on endogenous particles' detachment and redistribution remain notably underexplored. In this study, real-time in-situ CT was employed to observe the dynamic behavior of particle detachment, migration, and clogging induced by water flow in unconsolidated sandstone. The findings indicate that pore size is crucial in determining the size and quantity of detached particles. During the redistribution, the pore-throats lead to size-selective migration of particles, with particle concentration increasing along the flow direction and average radii decreasing. Additionally, three typical modes of particle clogging were identified including throat bridging, pathway retention, and pore clogging. This study offers real-time visualization of particle detachment and redistribution, elucidating the control mechanism by which pore structure governs these processes.
{"title":"Pore-scale controls on detachment and redistribution of endogenous particles induced by water flow in unconsolidated sandstone","authors":"Yuanping Li , Jingwei Huang , Chenyue Xie , Hui Zhao , Xiaolong Yin","doi":"10.1016/j.powtec.2025.122065","DOIUrl":"10.1016/j.powtec.2025.122065","url":null,"abstract":"<div><div>Fluid-driven particle transport represents a common phenomenon in subsurface flow. However, the pore-scale controls on endogenous particles' detachment and redistribution remain notably underexplored. In this study, real-time in-situ CT was employed to observe the dynamic behavior of particle detachment, migration, and clogging induced by water flow in unconsolidated sandstone. The findings indicate that pore size is crucial in determining the size and quantity of detached particles. During the redistribution, the pore-throats lead to size-selective migration of particles, with particle concentration increasing along the flow direction and average radii decreasing. Additionally, three typical modes of particle clogging were identified including throat bridging, pathway retention, and pore clogging. This study offers real-time visualization of particle detachment and redistribution, elucidating the control mechanism by which pore structure governs these processes.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"471 ","pages":"Article 122065"},"PeriodicalIF":4.6,"publicationDate":"2025-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145839642","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this work, an innovative and green synthesis method without using any toxic amine is developed to produce monodisperse polyurea microcapsules with a uniform size from 80 to . Phase separation phenomena in the polyurea microcapsules are identified for the first time, resulting from the slowed polymerization kinetics associated with the amine-free approach. The hydrophobicity and polarity of the organic solvents, together with the reactivity of polyisocyanates, can have a significant influence on the final structure of polyurea microcapsules. Moreover, the resulting structure of polyurea microcapsule strongly affects the conversion rate of the polyisocyanates. Classical spreading theory is verified to be efficient for explaining the phase separation, and a positive spreading coefficient for polyurea phase is essential for achieving a core–shell structure in the microcapsules.
{"title":"Phase separation phenomenon during green synthesis of polyurea microcapsules","authors":"Jiupeng Du , Zhiren Shen , Mohamad Abou Chahine , Alain Tonetto , Pierrette Guichardon","doi":"10.1016/j.powtec.2025.122045","DOIUrl":"10.1016/j.powtec.2025.122045","url":null,"abstract":"<div><div>In this work, an innovative and green synthesis method without using any toxic amine is developed to produce monodisperse polyurea microcapsules with a uniform size from 80 to <span><math><mrow><mn>110</mn><mspace></mspace><mi>μ</mi><mi>m</mi></mrow></math></span>. Phase separation phenomena in the polyurea microcapsules are identified for the first time, resulting from the slowed polymerization kinetics associated with the amine-free approach. The hydrophobicity and polarity of the organic solvents, together with the reactivity of polyisocyanates, can have a significant influence on the final structure of polyurea microcapsules. Moreover, the resulting structure of polyurea microcapsule strongly affects the conversion rate of the polyisocyanates. Classical spreading theory is verified to be efficient for explaining the phase separation, and a positive spreading coefficient for polyurea phase is essential for achieving a core–shell structure in the microcapsules.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"470 ","pages":"Article 122045"},"PeriodicalIF":4.6,"publicationDate":"2025-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145836713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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