Journal of Micromechanics and Molecular Physics最新文献_第6页

Characterization of a soft magnetic composite for use in road-embedded wireless-charging systems 用于道路嵌入式无线充电系统的软磁复合材料的特性

Journal of Micromechanics and Molecular Physics Pub Date : 2021-12-28 DOI: 10.1142/s2424913021430062

Kaiwei Li, Bill Trompetter, M. Amirpour, T. Allen, S. Bickerton, P. Kelly

{"title":"Characterization of a soft magnetic composite for use in road-embedded wireless-charging systems","authors":"Kaiwei Li, Bill Trompetter, M. Amirpour, T. Allen, S. Bickerton, P. Kelly","doi":"10.1142/s2424913021430062","DOIUrl":"https://doi.org/10.1142/s2424913021430062","url":null,"abstract":"The ferrite magnetic core is an integral component of road-embedded wireless charging systems for electric vehicles. However, the brittleness of ferrite makes it susceptible to premature fracture due to cyclic wheel loading from vehicles. This has motivated the development of a soft magnetic composite (SMC) composed of a flexible polyurethane and crushed ferrite as an alternative. An experimental investigation was conducted into the trade-offs between mechanical, thermal and magnetic properties at ferrite volume fractions between 45.9[Formula: see text]vol% and 80.6[Formula: see text]vol%. A comparison was made between measured properties and predictions from analytical models in order to further investigate the characteristics of the composite. The investigation showed a trade-off between the increase in magnetic permeability and the reduction in strain-to-failure as ferrite volume fraction increased. In addition, a large increase in flexural modulus and thermal conductivity, along with a slight increase in flexural strength was observed. More importantly, the strain-to-failure of the composite was 20 times higher than that of ferrite even at the highest volume fraction, indicating that the SMC was successful in providing a more ductile and flexible alternative.","PeriodicalId":36070,"journal":{"name":"Journal of Micromechanics and Molecular Physics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44470312","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

A study on the mechanical polishing technique by using shear thickening fluids 剪切增稠液机械抛光技术的研究

Journal of Micromechanics and Molecular Physics Pub Date : 2021-12-22 DOI: 10.1142/s2424913021430037

L. Chang, Ziyan Man, Lin Ye

引用次数: 1

Thermal residual stresses in thermoplastic CFRP-steel laminates: Modification and influence on fatigue life 热塑性cfrp -钢层合板的热残余应力:改性及其对疲劳寿命的影响

Journal of Micromechanics and Molecular Physics Pub Date : 2021-12-22 DOI: 10.1142/s2424913021430050

J. Hausmann, Stefan Schmidt

{"title":"Thermal residual stresses in thermoplastic CFRP-steel laminates: Modification and influence on fatigue life","authors":"J. Hausmann, Stefan Schmidt","doi":"10.1142/s2424913021430050","DOIUrl":"https://doi.org/10.1142/s2424913021430050","url":null,"abstract":"Thermal residual stresses (TRS) in hybrid materials and structures occur by the mismatch of thermal expansion of different materials. Especially when combining metals with carbon fiber reinforced plastics (CFRP), a significant level of internal stresses can be reached. High processing temperatures and high stiffness of the constituents are also responsible for high stress levels. Laminates of thermoplastic CFRP (unidirectional carbon fiber reinforced polyamide 6) and stainless steel foils are a suitable material system to examine the TRS in detail. Since TRSs in the steel fraction are of tensile nature, these superpose to externally applied loads, resulting in higher efforts for the material and thus reduced lifetimes under cyclic fatigue loading. Therefore, a reduction of TRS is desired. Two methods for TRS reduction were applied, and its influence on fatigue lifetime was investigated. Firstly, specimens were stretched by a preloading to reduce TRS by yielding of the metal. Secondly, non-symmetric laminates were gradually cooled down after consolidation to compensate TRS formation by non-symmetric shrinkage. While preloading of materials and structures is known for TRS modification, the gradually cooling is not established, yet. Both modification principles were numerically investigated before experimental validation. A significant increase of lifetime was reached by TRS reduction.","PeriodicalId":36070,"journal":{"name":"Journal of Micromechanics and Molecular Physics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49018643","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Preface: Special Issue of Professor Eringen's Centennial Anniversary — Part I 前言：埃林根教授百年诞辰特刊——上

Journal of Micromechanics and Molecular Physics Pub Date : 2021-12-01 DOI: 10.1142/s2424913021020033

James D. Lee, Jiaoyan Li, Leyu Wang

引用次数: 0

The effects of printing directions on the compression behavior of the Re-entrant structure produced by 3D printing technology 打印方向对3D打印技术生产的凹入结构压缩行为的影响

Journal of Micromechanics and Molecular Physics Pub Date : 2021-11-30 DOI: 10.1142/s2424913021410046

Hang Dong, L. Chang

引用次数: 1

Donnan equilibrium revisited: Coupling between ion concentrations, osmotic pressure, and donnan potential 重新审视唐纳平衡:离子浓度、渗透压和唐纳电位之间的耦合

Journal of Micromechanics and Molecular Physics Pub Date : 2021-11-24 DOI: 10.1142/s2424913021420145

Gang Chen

引用次数: 4

Virial theorems and virial stresses of micropolar media 微极性介质的维里定理和维里应力

Journal of Micromechanics and Molecular Physics Pub Date : 2021-11-19 DOI: 10.1142/s2424913021420066

M. Ostoja-Starzewski

引用次数: 1

3D printing of metallic micro-gears for micro-fluidic applications 用于微流体应用的金属微齿轮的3D打印

Journal of Micromechanics and Molecular Physics Pub Date : 2021-10-29 DOI: 10.1142/s2424913021410022

C. Wang, S. Chandra, X. Tan, S. Tor

{"title":"3D printing of metallic micro-gears for micro-fluidic applications","authors":"C. Wang, S. Chandra, X. Tan, S. Tor","doi":"10.1142/s2424913021410022","DOIUrl":"https://doi.org/10.1142/s2424913021410022","url":null,"abstract":"Micro-fluidic devices are essential to handle fluids on the micro-meter scale (micro-scale), making them crucial to biomedical applications, where micro-gear is the key component for active fluid mixing. Rapid and direct fabrication of micro-gears is preferred because they are usually custom-made to specific applications and iterative design is needed. However, conventional manufacturing (CM) techniques for micro-fluidic devices are labor-intensive and time-consuming as multiple steps are required. Three-dimensional (3D) printing, or formally known as additive manufacturing (AM) offers a promising alternative over CM techniques in producing near-net shape complex geometries, given the micro-scale fabrication process. In this work, two types of powder-bed fusion (PBF) AM techniques, namely laser-PBF (L-PBF) and electron beam-PBF (EB-PBF) are used to benchmark 3D-printed micro-gears from stainless steel 316L micro-granular powders. Results showcase the preeminence of L-PBF over EB-PBF in generating distinguishable micro-scale features on gear profiles and superior micro-hardness in mechanical property. Overall, PBF metal AM shows significant promise in advancing the otherwise tedious state of CM for micro-gears.","PeriodicalId":36070,"journal":{"name":"Journal of Micromechanics and Molecular Physics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44915445","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

An overview of entropy principle 熵原理综述

Journal of Micromechanics and Molecular Physics Pub Date : 2021-10-25 DOI: 10.1142/s2424913021420017

I. Liu

引用次数: 0

Experimental investigation of modified co-curing process for carbon fiber/epoxy-laminates 碳纤维/环氧复合材料改性共固化工艺的实验研究

Journal of Micromechanics and Molecular Physics Pub Date : 2021-10-08 DOI: 10.1142/s2424913021430013

Nicole Motsch-Eichmann, F. Rieger, Thomas Rief, J. Hausmann

{"title":"Experimental investigation of modified co-curing process for carbon fiber/epoxy-laminates","authors":"Nicole Motsch-Eichmann, F. Rieger, Thomas Rief, J. Hausmann","doi":"10.1142/s2424913021430013","DOIUrl":"https://doi.org/10.1142/s2424913021430013","url":null,"abstract":"In this study, thermoset-based carbon fiber-reinforced polymer structures manufactured by the so-called modified co-curing process are analyzed and compared to well-established co-curing and co-bonding. The modified co-curing process allows manufacturing geometrically complex parts without traditional core technologies by producing laminates from a un-cured half and a pre-cured half in contrast to using two un-cured halves (co-curing) or a fully cured half plus an un-cured half (co-bonding). The interlaminar fracture toughness under Mode I loading, [Formula: see text], was determined in double cantilever beam (DCB) tests. [Formula: see text] displays a correlation of the degree of cure and the joint properties, with the co-curing laminates having 11% and 33% higher fracture toughness than the modified co-curing configurations. However, modified co-curing in all cases results is superior or equal to co-bonding. To assess the influence of surface properties for the bonding quality, different peel plies were compared with respect to the resulting joint properties. The results with up to 50% loss in [Formula: see text] values indicate the high importance of appropriate surface preparation. Subsequent tests also show that the negative influence of the peel ply on the joint properties can be reversed by abrasive surface treatment. It was found that at higher degrees of partial curing before co-curing, crack growth increasingly occurs in the interface of the bonded laminates. Therefore, the properties of the surface before joining were analyzed and modified to assess its relevance for the bonding properties and the potential for improvement.","PeriodicalId":36070,"journal":{"name":"Journal of Micromechanics and Molecular Physics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48302315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2