{"title":"Microstructural Changes During Annealing of Aluminum Alloy: Modeling","authors":"S. Shabaniverki, S. Serajzadeh","doi":"10.1201/9781351045636-140000226","DOIUrl":"https://doi.org/10.1201/9781351045636-140000226","url":null,"abstract":"Determination of microstructural events during heat treatment operations is an important task to obtain the desired microstructures and mechanical properties. Accordingly, during heat treatment of materials that have high stalking fault energy such as aluminum alloys, concurrent occurrence of recovery and recrystallization needs to be considered. On the other hand, the annealing processes may be performed under non-isothermal conditions in which a part of softening process is carried out during heating and/or cooling stage, particularly for the case of large-scale products. Thus, for estimation of softening fraction and microstructural events, different types of problems need to be taken into account such as the deformation analysis, the kinetics of metallurgical events, and heat conduction problem. In this entry, a combined analysis is discussed to manage the above-mentioned phenomena employing the finite element analysis together with cellular automata (CA) modeling. For this purpose, the distribution of plastic strain and the stored energy after cold rolling are determined utilizing finite element formulation, while they are considered as the initial conditions for the microstructural modeling. In the next stage, a two-dimensional CA coupled with a first-order equation is used to assess the softening rate, while a thermal finite element analysis is simultaneously employed to define temperature distribution during non-isothermal annealing. The model is then examined on softening behavior of cold-rolled AA1050 plate.","PeriodicalId":348912,"journal":{"name":"Encyclopedia of Aluminum and Its Alloys","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123764799","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}
{"title":"The Crystallography of Aluminum and Its Alloys","authors":"P. Nakashima","doi":"10.1201/9781351045636-140000245","DOIUrl":"https://doi.org/10.1201/9781351045636-140000245","url":null,"abstract":"This article begins with pure aluminum and a discussion of the form of the crystal structure and different unit cells that can be used to describe it. Measurements of the face-centered cubic lattice parameter and thermal expansion coefficient in pure aluminum are reviewed and parametrizations are given which allow the reader to evaluate them across the full range of temperatures where aluminum is a solid. A new concept called the “vacancy triangle” is introduced and demonstrated as an effective means for determining vacancy concentrations near the melting point of aluminum. The Debye–Waller factor, quantifying the thermal vibration of aluminum atoms in pure aluminum, is reviewed and parametrized over the full range of temperatures where aluminum is a solid. The nature of interatomic bonding and the history of its characterization in pure aluminum are reviewed with the unequivocal conclusion that it is purely tetrahedral in nature. The crystallography of aluminum alloys is then discussed in terms of all of the concepts covered for pure aluminum, using prominent alloy examples. The electron density domain theory of solid-state nucleation and precipitate growth is introduced and discussed as a new means of rationalizing phase transformations in alloys from a crystallographic point of view.","PeriodicalId":348912,"journal":{"name":"Encyclopedia of Aluminum and Its Alloys","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125176694","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}
{"title":"Thermal Analysis of Aluminum Alloys","authors":"D. Larouche","doi":"10.1201/9781351045636-140000168","DOIUrl":"https://doi.org/10.1201/9781351045636-140000168","url":null,"abstract":"Thermal analysis is applied on aluminum alloys by researchers to investigate mainly phase transformations, while it is regularly used for quality control purposes in industry. Techniques like cooling curve analysis, differential thermal analysis, differential scanning calorimetry, and isothermal calorimetry are amongst those most frequently used by scientists and engineers. These techniques will be described, and a mathematical description of the results will be developed. State-of-the-art quantification methods applied on aluminum alloys will be presented and criticized based on specific examples taken from the literature.","PeriodicalId":348912,"journal":{"name":"Encyclopedia of Aluminum and Its Alloys","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133501533","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}
{"title":"Polyphase Eutectics of Aluminum Alloys: Effect of Phase Composition","authors":"M. Warmuzek","doi":"10.1201/9781351045636-140000255","DOIUrl":"https://doi.org/10.1201/9781351045636-140000255","url":null,"abstract":"The polyphase eutectics (α-Al+intermetallic+Si) constituting the final aluminum alloy microstructure were characterized by their phase composition, growth mechanism, and morphology of eutectic crystals. The main groups of eutectic phase constituents were presented with a special attention paid to intermetallic phases. Morphology of different types of polyphase eutectics, among those divorced, was characterized and presented (as microscopic images) on microphotographs. The microstructural effects of stable and metastable phases competition in the stage of nucleation and growth of polyphase eutectics as affected by local cooling rate and liquid alloy composition were described. Some examples of the evolution of the phase composition of eutectics in commercial alloys due to modifications of technological procedures were presented.","PeriodicalId":348912,"journal":{"name":"Encyclopedia of Aluminum and Its Alloys","volume":"5 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130370980","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}
{"title":"Plastic Flow of Aluminum in Explosive Welding","authors":"V. Petushkov, M. I. Zotov, L. Dobrushin","doi":"10.1201/9781351045636-140000439","DOIUrl":"https://doi.org/10.1201/9781351045636-140000439","url":null,"abstract":"Joining of metals in explosive welding takes place as a result of their plastic deformation during a high speed collision and is usually accompanied by typical formation of waves at the interface. In welding aluminium, the weld boundary can also be straight if the speed of the contact point is νc is ≤ 1900 m/s. These welding conditions make it possible to prevent melting of the metal at the interface and increase at the same time its corrosion resistance. In this article, the effect of the dynamic collision angle on the special features of plastic flow of the metal in the vicinity of the contact boundary in welding sheets of AS5 aluminium is described.","PeriodicalId":348912,"journal":{"name":"Encyclopedia of Aluminum and Its Alloys","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122627798","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}
{"title":"Electrical Conductivity of Aluminum Alloy A2011","authors":"S. Bakhtiyarov, R. Overfelt","doi":"10.1201/9781351045636-140000251","DOIUrl":"https://doi.org/10.1201/9781351045636-140000251","url":null,"abstract":"A rotational, contactless inductive measurement technique has been used to determine the effect of pores and metallic insertions on the electrical resistivity of A2011 aluminum alloy at different temperatures. It is shown that the electrical resistivity increases with the total volume of pores and is also dependent on the pores locations and orientation. Additional energy losses were found on the contact surfaces between sample and insertions.","PeriodicalId":348912,"journal":{"name":"Encyclopedia of Aluminum and Its Alloys","volume":"113 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124148486","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}
{"title":"Aircraft Structural Integrity: Corrosion Effects","authors":"B. Crawford, C. Loader, T. Harrison","doi":"10.1201/9781351045636-140000250","DOIUrl":"https://doi.org/10.1201/9781351045636-140000250","url":null,"abstract":"Corrosion damage can significantly reduce the structural integrity of aluminum alloy components in aircraft. This is a serious threat to the airworthiness of aircraft which means that corrosion prevention and repair are a major cost to aircraft operators. This article details a practical approach to the management of corrosion in aircraft by describing the forms of corrosion that are common in aircraft, the detection and measurement of these forms, and how they affect the airworthiness of aircraft designed using the dominant airworthiness philosophies. It concludes with a brief outline of how the structural integrity effects of each type are modeled.","PeriodicalId":348912,"journal":{"name":"Encyclopedia of Aluminum and Its Alloys","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131120403","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}
{"title":"Fatigue Lifetime Improvement of Aluminum Alloys","authors":"P. Juijerm, B. Scholtes","doi":"10.1201/9781351045636-140000297","DOIUrl":"https://doi.org/10.1201/9781351045636-140000297","url":null,"abstract":"Today, aluminum alloys are being considered as substitutes for many automotive parts made from steels because of the growing interest in producing lightweight vehicles. Consequently, it is crucial to understand the fatigue lifetime—the property itself and its behavior—of aluminum alloys, and to clarify its capacities at both room temperature and 1001 elevated temperatures. In particular, the aluminum alloys in the AA5xxx (non-precipitation-hardenable) and AA6xxx (precipitation-hardenable) series are very similar to those found in automotive industries, and are both frequently mentioned and the focus of studies. The satisfactory fatigue lifetime and the improved strength of aluminum alloys make them a strong candidate for automotive industries. This article focuses upon the fatigue property and behavior of aluminum alloys at room temperature and elevated temperatures. Then, the focus will shift to the concept of mechanical surface treatment, the so-called deep-rolling process, which can be used to improve the fatigue lifetime of aluminum alloys. The effects of a mechanical surface treatment on the fatigue properties and behavior of the aluminum alloys AA5083 and AA6110, and the residual stress stability at room temperature and elevated temperatures has been discussed. Moreover, modified deep-rolling processes, i.e., deep-rolling followed by an appropriate annealing process and high-temperature deep-rolling, have been elaborated upon in this article.","PeriodicalId":348912,"journal":{"name":"Encyclopedia of Aluminum and Its Alloys","volume":"61 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131325562","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}
{"title":"Microstructure and Yield Strength Evolution of Aluminum Alloys","authors":"Kai Li, Yong Du, M. Song","doi":"10.1201/9781351045636-140000222","DOIUrl":"https://doi.org/10.1201/9781351045636-140000222","url":null,"abstract":"Aluminum alloys are light materials with high strength-to-weight ratio, corrosion resistance, and excellent formability. Due to these advantages, they are widely used in many industrial applications such as fabrication of aeroplanes, automobiles, ships, and architectural structures. Many fabrication parameters, such as alloy composition, casting and solidification conditions, strain rate, and ageing conditions, strongly affect the microstructural features such as morphology of phases, solute-dislocation interactions, as well as size and volume fraction of strengthening precipitates, and therefore determine the mechanical properties especially yield strength. This chapter probes microstructural optimization of aluminum alloys and the relationship between their microstructures and yield strength, with emphases on recent progress in microstructural modification of Al-Si alloys, yield strength modeling of dynamic strain ageing in Al-Mg alloys, and modeling of precipitate strengthening in Al-Mg-Si(-Cu) alloys.","PeriodicalId":348912,"journal":{"name":"Encyclopedia of Aluminum and Its Alloys","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128826509","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}
{"title":"Sintering Behavior: Al–SiC Compacts in Different Atmospheres","authors":"T. Pieczonka","doi":"10.1201/9781351045636-140000292","DOIUrl":"https://doi.org/10.1201/9781351045636-140000292","url":null,"abstract":"The effect of sintering atmosphere on densification of Al–SiC compacts was investigated. Dimensional changes were monitored in situ in a dilatometer in flowing nitrogen, nitrogen/hydrogen mixture (95/5 by volume), and argon. Two grades of SiC powder were used—F240 characterized by large particles and FCN13 with very fine particles. Mixtures containing 10 and 30 vol.% of SiC reinforcement were prepared in a Turbula mixer. Green compacts of about 80% of theoretical density were made of each mixture. For comparison, compacts made of pure aluminum powder were also investigated. It was shown that nitrogen is the only sintering atmosphere producing shrinkage. This ceramic constituent lowers the sintering densification. Metallographic examinations of sintered composites revealed that sintering of compacts occurs in the presence of a liquid phase exclusively in nitrogen. The melt appearing in Al–SiC compacts is capable to wet the solid phases, which makes shrinkage possible and is beneficial for metal/ceramic bond formation.","PeriodicalId":348912,"journal":{"name":"Encyclopedia of Aluminum and Its Alloys","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127277911","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}
京公网安备 11010802042870号
求助内容：
应助结果提醒方式：