现代机械工程(英文)最新文献_第5页

Tool Temperature and Process Modeling of Friction Stir Welding 搅拌摩擦焊的工具温度和过程建模

现代机械工程(英文) Pub Date : 2018-01-16 DOI: 10.4236/MME.2018.81006

Takashi Nakamura, T. Obikawa, E. Yukutake, S. Ueda, I. Nishizaki

{"title":"Tool Temperature and Process Modeling of Friction Stir Welding","authors":"Takashi Nakamura, T. Obikawa, E. Yukutake, S. Ueda, I. Nishizaki","doi":"10.4236/MME.2018.81006","DOIUrl":"https://doi.org/10.4236/MME.2018.81006","url":null,"abstract":"Friction stir welding (FSW) has many advantages rather than fusion welding, but details of internal phenomena during its processes have not yet been clarified. In this study, a thermo-mechanically coupled process model was developed to investigate FSW phenomena inside a tool and workpiece. As a workpiece, 6061-T6 aluminum alloy was employed. The system of FSW process model includes several thermal boundaries. Among heat flows through these boundaries, heat transfers into the exterior of the system become more sensitive to tool and workpiece temperatures than heat transfers within the system. This paper especially focused on a heat transfer coefficient at a workpiece bottom, and optimized it through experiments and finite element method (FEM) analyses. The tool temperatures during FSW were measured with a special tooling system with imbedded thermocouples within a tool. As a result, an analysis model that is able to investigate details at a wide range of traverse speeds was developed for practical high speed welding. Then, the accuracy of developed FEM model was validated with them. Finally, the temperatures and stress distribution around workpiece/tool interfaces were investigated with the developed model.","PeriodicalId":69007,"journal":{"name":"现代机械工程(英文)","volume":"08 1","pages":"78-94"},"PeriodicalIF":0.0,"publicationDate":"2018-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47157683","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: 10

Failure Mechanism of O-Ring Seals under Extreme Operating Conditions 极端工况下o形密封圈失效机理研究

现代机械工程(英文) Pub Date : 2018-01-16 DOI: 10.4236/MME.2018.81002

G. Szabó, K. Varadi

{"title":"Failure Mechanism of O-Ring Seals under Extreme Operating Conditions","authors":"G. Szabó, K. Varadi","doi":"10.4236/MME.2018.81002","DOIUrl":"https://doi.org/10.4236/MME.2018.81002","url":null,"abstract":"In this paper the behavior of an O-ring made of NBR rubber was investigated under extreme conditions. The effect of the extreme initial compression, operating pressure and extreme temperature conditions were examined. The rubber material was tested in simple tension, pure shear and equibiaxial tension modes complemented with a Dynamic Mechanical Thermal Analysis (DMTA) to capture the viscoelastic behavior of the material. For the investigation, a large-strain viscoelastic material model was developed by the authors, to take into account the large deformations caused by extreme conditions. Insufficient space during installation causes extreme initial compression consequently leading the material to crack on the contacting outer surfaces. It was found that the excessive strain and friction induced shear stress contributes primarily to this phenomenon. Extreme operating pressure causes the seal to penetrate into the gap between the shaft and the housing. This behavior damages the material and cracks appear on the seal. High strain areas were found in the proximity of the gap in the material. The analysis of the extreme operating temperature showed that during cooling the O-ring can completely loose its ability to seal at -70°C. There are three contributing factors: the speed of cooling, the temperature and the coefficient of thermal expansion.","PeriodicalId":69007,"journal":{"name":"现代机械工程(英文)","volume":"08 1","pages":"11-30"},"PeriodicalIF":0.0,"publicationDate":"2018-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46403856","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: 7

Optimization of Welding Parameters for Friction Stir Lap Welding of AA6061-T6 Alloy AA6061-T6合金搅拌摩擦搭接焊接参数优化

现代机械工程(英文) Pub Date : 2018-01-16 DOI: 10.4236/MME.2018.81003

R. Chandran, Sankar Ramaiyan, A. Shanbhag, S. Santhanam

{"title":"Optimization of Welding Parameters for Friction Stir Lap Welding of AA6061-T6 Alloy","authors":"R. Chandran, Sankar Ramaiyan, A. Shanbhag, S. Santhanam","doi":"10.4236/MME.2018.81003","DOIUrl":"https://doi.org/10.4236/MME.2018.81003","url":null,"abstract":"Friction Stir Welding (FSW) is currently used in many aircraft and aerospace sheet metal structures involving lap joints and there has been growing interest in recent years in utilizing this process for joining aluminum alloys. In this paper, Friction Stir Lap Welding (FSLW) of the 6061-T6 aluminum alloy was carried out to obtain the optimum welding condition for maximum shear strength where the rotational speed, axial load, and welding speed were taken as process parameters. An L-9 orthogonal array, a Taguchi Method with consideration of three levels and three factors was designed and executed for conducting trials. Analysis of variance (ANOVA) and Signal to Noise (S/N) ratio were employed to investigate the influence of different welding parameters on the shear strength and obtain the optimum parameters. The Fisher-Test was also implemented to find the design parameter which had the most important effect on the characteristic of quality. The results indicated that the tool rotational speed had the maximum percentage contribution (51%) on the response (shear strength) followed by the welding speed (38%) and the axial load (8%) while the percentage of error was 3%. However, to confirm the main effects for the means and S/N ratios of the experiment, theoretical shear strength values were computed to predict the tensile strength. The maximum shear strength of 60 MPa was achieved and the effectiveness of the method was confirmed. The optimum parameter combinations that provided higher shear strength were: rotational speed of 1200 rpm, welding speed of 45 mm/min and the axial load of 11.5 kN.","PeriodicalId":69007,"journal":{"name":"现代机械工程(英文)","volume":"08 1","pages":"31-41"},"PeriodicalIF":0.0,"publicationDate":"2018-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46542930","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: 16

The application of process mapping to create improvements in production logistics at the example of the shipbuilding industry plant 应用流程图改进生产物流——以造船厂为例

现代机械工程(英文) Pub Date : 2017-12-18 DOI: 10.15377/2409-9848.2017.04.04

K. Nadolny, Piotr Czerwik

引用次数: 1

Effect of Cooling Conditions on Mechanical and Microstructural Behaviours of Friction Stir Processed AZ31B Mg Alloy 冷却条件对搅拌摩擦处理AZ31B镁合金力学和微观组织行为的影响

现代机械工程(英文) Pub Date : 2017-11-28 DOI: 10.4236/MME.2017.74010

Sankar Ramaiyan, R. Chandran, S. Santhanam

引用次数: 13

Optimizing the Sandwich Composite Structure in the Cantilever Beam 悬臂梁夹层复合材料结构的优化设计

现代机械工程(英文) Pub Date : 2017-11-20 DOI: 10.4236/MME.2017.74009

Tuo Hu

引用次数: 1

Numerical Simulation on the Comb Drive Micro-Accelerometer 梳状微加速度计的数值模拟

现代机械工程(英文) Pub Date : 2017-10-12 DOI: 10.4236/MME.2017.74008

Xian-yang Zhao

引用次数: 0

Finite Element Model of a Filament-Wound Composite Tube Subjected to Uniaxial Tension 单轴拉伸作用下纤维缠绕复合材料管的有限元模型

现代机械工程(英文) Pub Date : 2017-10-12 DOI: 10.4236/MME.2017.74007

G. Szabó, K. Varadi, D. Felhős

引用次数: 10

Structural Design via Genetic Optimization 基于遗传优化的结构设计

现代机械工程(英文) Pub Date : 2017-08-31 DOI: 10.4236/MME.2017.73006

David J. Webb, Wissam M. Alobaidi, E. Sandgren

{"title":"Structural Design via Genetic Optimization","authors":"David J. Webb, Wissam M. Alobaidi, E. Sandgren","doi":"10.4236/MME.2017.73006","DOIUrl":"https://doi.org/10.4236/MME.2017.73006","url":null,"abstract":"Structural designs (i.e. truss structures) are derived by the use of a three phase genetic optimization approach, where the minimization of volume is the objective of each truss structure considered. A genetic algorithm is employed which controls the three phase optimization technique. The first phase utilizes the conventional functionality of the genetic algorithm from an evolutionary perspective, however designer interaction by the use of constant rules is provided to ensure an effective evolutionary search outcome. The second phase enhances the best design constructed from phase one by the use of domain specific knowledge in the form of design rules. Phase three improves the final design assembled within phase two by the reduction of truss element areas. This refinement process ensures that the design constraints provided are active, indicating an optimal search solution. All phases operate from a global perspective; however the phase two optimization methodology operates from a more radical approach which encompasses the concept of designing from a “blank sheet of paper” point of view. Results are provided upon the conclusion of each truss example considered which includes the outcomes of each phase for comparison purposes.","PeriodicalId":69007,"journal":{"name":"现代机械工程(英文)","volume":"07 1","pages":"73-90"},"PeriodicalIF":0.0,"publicationDate":"2017-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48412990","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

Influence of Loading on the Mechanical Response of Linked Structures of Two Steels: A Numerical Study 加载对两钢连接结构力学响应影响的数值研究

现代机械工程(英文) Pub Date : 2017-06-07 DOI: 10.15377/2409-9848.2017.04.01.03

T. Srivatsan, Prashant Gargh, Shivakumar Sastry

引用次数: 0