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金属注射成形烧结工艺的试验与数值模拟

机械工程学报 2008年第8期44卷 157-163页

作者：宋久鹏 BARRIERE Thierry 柳葆生 gelin jean-claude 西南交通大学应用力学与工程系成都610031 法国Femto-ST研究所应用力学实验室

采用粘塑性理论建立烧结过程的本构模型,以316L不锈钢粉末注射成形产品为例,设计出烧结过程中重力作用下弯曲梁试验和膨胀计中的自由烧结试验,分别用于标定本构模型中的粘度模量和烧结应力。通过用户子程序,在有限元求解器Abaqus^(?)上... 详细信息

采用粘塑性理论建立烧结过程的本构模型,以316L不锈钢粉末注射成形产品为例,设计出烧结过程中重力作用下弯曲梁试验和膨胀计中的自由烧结试验,分别用于标定本构模型中的粘度模量和烧结应力。通过用户子程序,在有限元求解器Abaqus^(?)上实现数值模拟,预测产品在烧结过程中的收缩和变形。考虑了重力、摩擦以及注射阶段粉末与粘结剂的偏析效应对于烧结工艺的影响,数值模拟结果与试验结果一致。

关键词：金属注射成形烧结粘塑性有限元法

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氧化铝陶瓷粉末固相烧结过程模拟

西南交通大学学报 2008年第2期43卷 275-279页

作者：宋久鹏 BARRIERE Thierry 柳葆生 gelin jean-claude 西南交通大学应用力学与工程系四川成都610031 Femto-ST研究所应用力学实验室法国贝桑松25000

用膨胀计测量了氧化铝粉末注射成形的烧结过程中试件的单轴收缩率和收缩速率.基于试验数据,设计了相应的参数标定算法,用于确定烧结模型中的单轴粘度和烧结应力.以氧化铝人工髋关节植体为例,将该模型和参数引入到有限元软件Abaqus中实... 详细信息

用膨胀计测量了氧化铝粉末注射成形的烧结过程中试件的单轴收缩率和收缩速率.基于试验数据,设计了相应的参数标定算法,用于确定烧结模型中的单轴粘度和烧结应力.以氧化铝人工髋关节植体为例,将该模型和参数引入到有限元软件Abaqus中实现数值模拟,以预测试件在烧结过程中的收缩和变形.结果表明,用标定的参数的模拟结果与试验结果基本吻合.

关键词：烧结注射成形收缩率氧化铝陶瓷标定数值模拟

316L不锈钢粉末注射成形件的烧结致密化行为

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材料科学与工艺 2010年第3期18卷 330-334页

作者：宋久鹏 Barriere Thierry 柳葆生 gelin jean-claude 西南交通大学应用力学与工程系成都610031 法国Femto-ST研究所应用力学实验室贝桑松25000

为了控制粉末注射成形零件的最终尺寸精度和力学性能,对316L不锈钢粉末注射成形件的烧结致密化行为进行了试验研究,分析了烧结温度和升温速率对试件致密化行为以及烧结件力学性能的影响.试验结果表明,致密化过程始于1080℃左右,主要在1... 详细信息

为了控制粉末注射成形零件的最终尺寸精度和力学性能,对316L不锈钢粉末注射成形件的烧结致密化行为进行了试验研究,分析了烧结温度和升温速率对试件致密化行为以及烧结件力学性能的影响.试验结果表明,致密化过程始于1080℃左右,主要在1200～1300℃的升温过程中快速进行,致密化速率随着升温速率的升高而升高.烧结件的抗拉强度、抗弯强度以及延伸率,不但取决于致密化程度,而且与微观结构有关.分析表明,将基于扩散控制和强度控制的烧结理论结合,可以有效地解释316L不锈钢粉末的致密化行为,需在现有的烧结模型中考虑强度影响因素,才能更真实地模拟烧结过程.

关键词：金属注射成形烧结致密化强度不锈钢

Bi-phasic Simulation of Metal Injection Moulding:Constitutive Determinations

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Journal of Southwest Jiaotong University(English Edition) 2003年第2期11卷 122-130页

作者：柳葆生 Barriere Thierry gelin jean-claude Department of Engineering Mechanics Southwest Jiaotong University LMARC Franche-Comt University

To predict the segregation effect in metal injection moulding (MIM) injection, a bi-phasic model based on mixture theory is adopted in simulation. An explicit algorithm is developed and realized by the authors, which conducts the simulation to be a cost-effective tool in MIM technology. In case of the bi-phasic simulation, the viscosity behaviours are necessary to be determined for the flows of each phase while only the viscosity of mixture is measurable by tests. It is a crucial problem for application of the bi-phasic simulation of MIM injection. A reasonable method is hence analysed and proposed to determine the viscosity behaviours of each phase. Even though this method may be furthermore modified in the future, it results in the practical simulation of segregation effects with reasonable parameters. The simulation results are compared with the measurements on injected specimens.

关键词： metal injection moulding bi-phasic simulation viscous behaviours mixture theory

Deep eutectic solvent-driven self-assembly of metal mercaptide complexes with enzyme-mimicking activities for detection of uric acid through one-step cascade catalytic reaction

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Green Chemical Engineering 2024年第1期5卷 75-84页

作者： jean claude Munyemana Jia Chen Xin Li Yangxia Han Hao Tang Hongdeng Qiu CAS Key Laboratory of Chemistry of Northwestern Plant Resources and Key Laboratory for Natural Medicine of Gansu Province Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou730000China University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing100039China Department of Pharmacy Gansu Provincial HospitalLanzhou730000China

This work presents a generic strategy to create a series of metal mercaptides complexes via coordination selfassembly between transition metals(Mn,Cu,Co,Fe,and Ni)and cysteine(Cys)by forming the sulfur-metal *** strategy involves dissolving metal chlorides and Cys into deep eutectic solvents(DES),followed by the precipitation of metal mercaptides complexes(such as Cys-Mn)by adding water as an antisolvent,where DES serves as the solvent,shape directing,and capping agent,thereby preventing the formation of other metal ***,the prepared complexes possess both laccase and peroxidase-like properties,allowing the design of a technique for the detection of L-3,4-dihydroxyphenylalanine(L-DOPA)and uric acid,*** prepared Cys-Mn can linearly oxidize L-DOPA with its concentrations from 0.1 to 130μM and the detection limit was calculated to be 75.5 n ***,the Cys-Mn can mimic the activity of peroxidase towards oxidization of o-phenylenediamine at neutral p H,allowing single-step and one-pot cascade reactions for visual and fluorometric measurements of uric acid(UA)that could work in the range of 0.2-500μM UA with a detection limit of 0.06μM and 0.054μМ,*** assay was successful in detecting UA in serum and urine samples with relative standard deviation(RSD)ranging from 7.3%to 10.2%and 3.0%-8.5%respectively,suggesting that it may prove useful in medical diagnostic testing.

关键词： Metal-mercaptides Deep eutectic solvents Self-assembly Peroxidase-mimic catalyst Uric acid detection

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粉末注射成形中偏析效应及其影响的数值模拟

应用力学学报 2008年第1期25卷 33-37页

作者：宋久鹏 Barriere Thierry 柳葆生 gelin jeanclaude 西南交通大学成都610031 Femto-ST研究所应用力学实验室法国贝桑25000

在金属或陶瓷粉末注射成形中,由于粉末与粘结剂的密度差异,二者在高速充模的过程中会产生局部比例变化,即偏析现象。针对偏析现象,采用两相流注射模型,将注射喂料视为由粉末相和粘结剂相组成的混合流体,预测注射成形坯件中粉末相和粘结... 详细信息

在金属或陶瓷粉末注射成形中,由于粉末与粘结剂的密度差异,二者在高速充模的过程中会产生局部比例变化,即偏析现象。针对偏析现象,采用两相流注射模型,将注射喂料视为由粉末相和粘结剂相组成的混合流体,预测注射成形坯件中粉末相和粘结剂相的分布。将结果引入到后续的烧结模拟中,宏观烧结模型采用基于热弹粘塑性的本构关系。据此模拟产品在烧结过程中发生的收缩和变形以及预测产品在烧结过程中现场强度(In-situ strength)。模拟结果说明注射坯件的非匀质性导致产品的烧结过程中产生非均匀收缩和内部应力的大幅度上升,影响产品的精度和性能。这种从注射到烧结的模拟体系可用于优化粉末注射成形工艺的喂料设计、模具设计以及注射和烧结工艺参数的选取。

关键词：粉末注射成形烧结数值模拟

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MIM零件烧结过程中收缩和变形的数值模拟

机械科学与技术 2007年第8期26卷 1045-1049页

作者：宋久鹏 Barriere Thierry 柳葆生 gelin jean-claude 西南交通大学应用力学与工程系成都610031 Femto-ST研究所应用力学实验室法国贝桑松25000

为描述金属粉末注射成形坯件在烧结过程中的收缩和变形行为,基于连续介质力学原理建立了符合粘塑性本构关系的宏观烧结模型。该模型通过有限元软件Abaqus的用户子程序实现,进行烧结过程的数值模拟。分析了由于坯件重力、非均匀初始密度... 详细信息

为描述金属粉末注射成形坯件在烧结过程中的收缩和变形行为,基于连续介质力学原理建立了符合粘塑性本构关系的宏观烧结模型。该模型通过有限元软件Abaqus的用户子程序实现,进行烧结过程的数值模拟。分析了由于坯件重力、非均匀初始密度分布以及坯件支承体之间的摩擦力等因素而引起的非均匀收缩和变形。通过与试验结果的比较,验证了烧结模型和数值方法的正确性。

关键词：金属注射成形烧结数值模拟

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升温速率对氧化铝粉末烧结行为的影响

材料导报 2007年第3期21卷 144-146页

作者：宋久鹏 Barriere Thierry 柳葆生 gelin jean-claude 西南交通大学应用力学与工程系成都610031 法国Femto-ST研究所应用力学实验室贝桑松25000

采用不同的升温速率,在膨胀计中对脱脂后的氧化铝粉末射成形坯件进行一系列的烧结试验。结果表明,烧结致密化过程主要发生在升温阶段,快速升温有利于致密化的进行和抑止晶粒长大,但由于烧结时间较短和烧结炉最高温度的限制,产品的最终... 详细信息

采用不同的升温速率,在膨胀计中对脱脂后的氧化铝粉末射成形坯件进行一系列的烧结试验。结果表明,烧结致密化过程主要发生在升温阶段,快速升温有利于致密化的进行和抑止晶粒长大,但由于烧结时间较短和烧结炉最高温度的限制,产品的最终致密化程度不高。在低温时快速升温,高温时缓慢加热,可以获得较好的致密化效果和微观结构。试验和分析结果将为建立非等温烧结模型和烧结工艺参数的优化方法提供依据。

关键词：粉末注射成形氧化铝烧结致密化晶粒长大

New Insights in the Biodegradability and the Ecotoxicological Effects of Solar Products Containing Mineral and Chemical UV-Filters on Marine Zoo- and Phytoplanktons: An in silico and in vitro Study

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Journal of Cosmetics, Dermatological Sciences and Applications 2024年第1期14卷 98-111页

作者： jean-claude Hubaud Karim Mekideche jean-Eric Branka Luc Lefeuvre HELIOSCIENCE Cité de la cosmétique 2 rue Odette Jasse Marseille France EPHYSCIENCE 498ter route de Saint Joseph de Porterie Nantes France Laboratoires Dermatologiques d’Uriage Neuilly-sur-Seine France

Background: Cosmetic formulations, and particularly solar products which contain mineral and chemical UV-filters, are often suspected of causing harmful effects on marine fauna and flora. After the publication of our work in 2019 concerning the ecotoxicological effects of such formulations on corals (Seriatopora hystrix), we here provide some new information about the biodegradability and the ecotoxicological effects of these products on marine zoo- and phytoplankton. Therefore, we choose to realize in silico and in vitro studies of the biodegradability of several solar products but also to evaluate the ecotoxicological effects of these products on one phytoplankton, i.e. Phaeodactylum tricornutum, and one zooplankton, i.e. Acartia tonsa, of a great importance for sea species survival (notably as sources of food). Materials and methods: Two different approaches were used to study the biodegradability of the tested products: One in silico method and an in vitro one. 2 solar products were involved in the in silico study which consisted in the determination of the degradation factor (DF) of each ingredient of the tested formulas in order to finally obtain their estimated biodegradability percentage. Already available data concerning each ingredient coupled to a computer model developed with one of our partners were used to achieve this study. The in vitro study involved 8 formulas containing UV-filters and was led by following the OECD 301 F guidelines. Ecotoxicological studies of 7 of the formulas containing UV-filters were for their part realized by following the ISO 10253 guidelines for the experiments led with Phaeodactylum tricornutum, and the ISO 14669 guidelines for the experiments led with Acartia tonsa. In these studies, the effect of each tested product on crustaceans’ mortality and algal growth inhibition was assessed. Results: The in silico study predicted that formulas containing chemical UV-filters display a high biodegradability (superior to the threshol

关键词： UV-Filters Chemical UV-Filter Biodegradability Ecotoxicology in silico in vitro Zooplankton Phytoplankton Phaeodactylum tricornutum Acartia tonsa