VA020

Aluminum Alloy AA7075 Truck Tire Valve Manufacturing Process for Aluminum Wheel Rims

Min Wu, Novus Device Corporation, and Tom Moyer, Haltec Corporation, USA

With the truck industry moving more toward the standardized use of aluminum tire rim for its truck vehicle wheels, it is time for the tire valve industry to use aluminum for truck tire valve applications. Currently, brass is used for all truck tire valves. Aluminum has a huge advantage when compared to brass, such as aluminum truck tire valves will not have dissimilar metal contact corrosion with aluminum tire rims; it is a major problem for brass valve use on aluminum wheels. If the manufacturing process cannot compete with brass because of cost, the tire valve industry many not be willing to change brass to aluminum for truck tire valve applications. In this paper, only the high strength alloy A7075 manufacturing process will be presented. The manufacturing process for an aluminum tire valves is quite different from brass; for example Solid Solution Heat-Treated and double artificially aged is a must to process A7075 alloy, but is has not been used in brass truck tire valve manufacturing.

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VA031

Changes to the Specification for Aluminum Structures

J. Randolph Kissell, The TGB Partnership, USA

Part I of the Aluminum Association's Aluminum Design Manual is the Specification for Aluminum Structures, which is updated every 5 years. Since compliance with this Specification is required by the International Building Code, changes to the Specification directly affect most building applications of aluminum extrusions in the United States. Furthermore, the Specification's provisions are used by other groups such as the American Welding Society (AWS) and the American Association of State Highway and Transportation Officials (AASHTO) in their standards on aluminum structural components. This paper reviews the changes to the most recent edition of the Specification, published in 2015.

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VA042

Influence of Anodizing Parameters on Surface Roughness & Dimensions of Anodized Extruded Aluminum Profiles (Anodizing Parameters: Etching time, Etch concentration, Temperature)

Mudar AlMekdad, Arif Hussain, and Mansoor Ali Khan, Gulf Extrusions Co. LLC, UAE

The main objective of this paper is to study the effect of the etching parameters such as etching time, etching concentration, temperature on the surface roughness and dimensions of the aluminum extrusions that are to be anodized, and also to estimate the actual change in surface roughness and actual change in the dimensions of the extruded aluminum in mill finish to post-anodized finish. Concept of this study came into actual work in order to control the rejection rate post anodizing of aluminum extrusions that is being used in industrial applications, such as manufacturing of pneumatic cylinders, actuator cases, etc. Rejection rate was comparatively high post anodizing of aluminum extrusions due to the inflexible dimensional controls and due to the variations in the control of surface roughness of the aluminum extrusions. Control on dimensions is an important and a very challenging task as an extruder and anodizer. Dimensions are controlled very well during the course of extrusion in order to meet specific tolerances set forth, but certain dimensions deviate post anodizing due to the etching process which is a sub-process during anodizing. The process of anodizing which comprises mainly of: degreasing, etching, desmutting, anodizing (formation of Al2O3 layer) and sealing. During Etching, there is a considerable loss of aluminum which is accounted for, and the dissolution of aluminum is completely dependent on the etching concentration, etching time and etching temperature. To an extent it is also dependent on the grade of alloy that is being anodized. Surface roughness is important for industrial components such as pneumatic cylinders and actuator cases. In the pneumatic industry it is one of the most controlled features with respect to use of aluminum extrusions considering the wearing of the component and also to assess the adhesion of the component with the surrounding metal or component. Hence, by this study we will be able to estimate the actual dimensional change and actual surface roughness change of the extruded aluminum in mill finish compared to that in the post-anodized finish and the factors/process parameters of the anodizing process that influence the dimensions and surface roughness, thereby setting a control limit at the extrusion phase and achieving the desired dimensions and roughness in the anodized finish in compliance to the requirements of both the end user and international requirements.

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VA045

Manufacturing of Shape Memory Metal Matrix Composites (SM-MMCs) by Composite Extrusion

Christoph Dahnke, Yannick Lorch, Matthias Haase, Nooman Ben Khalifa, and A. Erman Tekkaya, Institute of Forming Technology and Lightweight Construction, Technische Universität Dortmund, Germany

Shape memory alloys (SMA) are characterized by properties such as the shape memory effect, pseudo-elasticity or high damping properties. Due to those effects, which can be activated by a thermal or mechanical treatment, shape memory alloys are often referred to as intelligent or smart materials. As actuator components, for example, such smart materials have a high potential in innovative industrial applications. The combination of a SMA with a conventional lightweight alloy is especially interesting with regard to the increased importance of new lightweight strategies. Currently, the manufacturing of shape memory metal matrix composites (SM-MMCs) can be achieved analogously to the manufacturing of ordinary MMCs by a fiber or particle reinforcement. These processes are often cost intensive and require complex preparation. Continuous methods like composite extrusion have not been investigated for the manufacturing of SM-MMCs yet. Composite extrusion allows the continuous embedding of reinforcing or functional elements in an aluminum profile by the use of modified porthole dies. The process is characterized by advantageous properties like a simple guiding and defined positioning of the elements, as well as the applicability of conventional billets. In this paper the potential of manufacturing SM-MMCs by composite extrusion is analyzed.

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VA062

Flash Anodizing Process Integrated in a Vertical Coating Line for Aluminum Extrusions

Andrea Trevisan, SAT Surface Aluminium Technologies S.p.a., Italy

For high-chloride environments (sea areas, polluted areas) the international association for powder coating quality, QUALICOAT, recommends electrochemical pre-anodizing of the aluminum surface prior to coating in order to reduce the risk of corrosion. The aluminum oxide layer (thickness of 3÷8 microns, porous surface) is not sealed and represents the ideal substrate for powder adhesion. The innovation consists in performing the pre-anodizing process automatically and in line along with a vertical powder coating plant, with no handling and no delay between pre-anodizing and coating. That results in both higher quality and in a powder coating production cost comparable with standard pre-treatment process (chrome/chrome-free). A case study is presented: a vertical coating line installed in Vietnam (in collaboration with an American company) which features the possibility (in one single line) to switch the profiles, lot by lot, to chrome, chrome-free or flash-anodizing pre-treatment before powder coating.

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VA067

The Reversion Process Applied to a Plastic Working for High-Strength Aluminum Alloys

Katsuya Kato, Research & Development Division, UACJ Corporation; Yasuhiro Nakai and Tadashi Minoda, Division of Product Engineering, UACJ Extrusion Nagoya Corporation, Japan

Near net shape using plastic working is an effective method to reduce the cost of machining work and the waste of materials. If a high strength aluminum alloy such as the Al-Zn-Mg-Cu series aluminum alloy are processed using a plastic work, O temper condition materials are used. After the plastic working, a solution heat treatment and an artificial aging are applied to the materials. However, upon solution heat treatment, the product shape is deformed by cooling, and the material structure is changed. Therefore, by using materials of T4 temper, it is easier to obtain the required shapes of the products. On the other hand, the cold workability is affected by room temperature age hardening, and it decreases with the aging. It is known that the workability is improved by a reversion process before working, but there are only a few examples of industrial use. In this study, the effect of the reversion process condition on the cold workability, especially the expandability of an Al-Zn-Mg-Cu alloy tube of T4 temper was investigated. We have developed a new alloy for plastic working with a reversion processand applied this alloy to the suspension parts of motorcycles.

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VA068

Innovative Product Design - Twisted Aluminum Profile at KAIA Airport Saudi Arabia

Arvind Kumar Sivakumar and Mansoor Ali Khan, Gulf Extrusions Co. LLC, UAE

The King Abdul Aziz International Airport, Jeddah, Kingdom of Saudi Arabia is one of the most prestigious projects in the Middle East and is known for its unique design and innovative 2 km façade. The façade was designed to meet the climatic nature of the region. It is designed to be energy efficient and is targeting to achieve LEED Gold status. The façade was designed to accommodate harsh conditions such as heat, dust, sandstorms, absence of rain, cleaning. The façade system was intelligently designed with an incorporated façade maintenance system. The architect of the project wanted to incorporate a 'twisted' rain screen façade in order to serve as a protection from the harsh dusty weather conditions and provide shading for ambient internal thermal comfort ability. The challenge however was to find a supplier who can provide 60o twisted aluminum sections and also needed to be PVDF coated. After many exhaustive searches conducted by the contractor and architect, the challenge was finally awarded to Gulf Extrusions. Gulf Extrusions studied this challenge carefully, designed a special extrusion and a machine to achieve this nearly impossible feat. The key challenges were: 1.) Design, Extrusion and Fabrication of twisted profile 2.) Required twisting of 430 mm wide and 6m long aluminum profile from 0 degrees to 60 degrees in a consistent pattern. In this paper the author will share our systematic planning and challenges faced for this special project, and will present a detailed walk through of this project from choosing the right aluminum alloy, countering the spring effect of aluminum extrusions to developing a bespoke machine for twisting the profile to 60 degrees, and finally conducting a special PVDF finish to the profile.

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VA083

Friction Stir Welding and the Role It Plays in Extruded Thermal Management Solutions

Chunming Alex Chen and Michael Tozier, Sapa Extrusions Americas, USA

Aluminum extrusion is an excellent material for thermal management applications because of its high thermal conductivity, complex shape, and cost effectiveness. Extruded aluminum heat sinks and enclosures have been widely used in various thermal management applications such as power electronics, LED lighting, telecommunication devices, automotive, and computers. However, the aluminum extrusion process has its limitations on extrudable shapes and sizes. For example, it is very difficult to extrude high performance heat sinks with tall fins and small gaps or large-scale LED fixtures. In order to meet the increasing demands of heat dissipation, Sapa has developed high performance thermal management solutions using Friction Stir Welding technology. In the presentation, we will demonstrate the applications of Friction Stir Welding technology in two typical thermal management solutions: modular heat sink and friction stir welded liquid coolers. By joining single-fin extrusions using friction stir welding, we are able to produce modular heat sinks with high fin ratios in excess of 40:1 and up to 20" width. We will also show a unique manufacturing method of liquid coolers that takes advantage of features that can be integrated into the extrusion profile together with Friction Stir Welding.

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VA087

Newest Developments in Composite Extrusion

Nooman Ben Khalifa, Christoph Dahnke, Daniel Pietzka, Annika Foydl, and A. Erman Tekkaya, Institute of Forming Technology and Lightweight Construction, Technische Universität Dortmund, Germany

The manufacturing of lightweight components requires a holistic technological approach covering the whole system “design-material-manufacturing”. By combining multiple materials in a single component, this system can be adjusted to the individual requirements of lightweight applications, as the type of and the share between the different materials determine the mechanical properties as well as the weight of the lightweight component. A promising approach to combine multiple materials, like aluminum and high strength steel, is composite extrusion. Discontinuously, steel reinforced aluminum profiles can be produced by inserting reinforcements into the aluminum billets and the subsequent co-extrusion of those billets. Furthermore, continuously steel wire reinforced profiles can be fabricated by inserting high-strength steel wires into the material flow using modified porthole dies. The main parameters influencing the reinforcement ratio, the extrusion force, as well as the material distribution for the individual processes, are analyzed by experimental and numerical investigations. In addition, examples of applications of the composite components produced with the different processes are shown.

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VA092     

Baseless Packaging System for Aluminum Extrusions

Richard Michael, Damir Merdovic, and Rick Stacchino, Capral Ltd.; and Sam Youm, Ozkor Pty Ltd., Australia

Currently, the majority of aluminum extrusion packaging utilizes a standard dimension timber base and/or side and top cleats. Integrity of the pack is dependent on the quality/tightness of strapping, which goes over the cleats. There are few deficiencies of this approach and some damage occurs during transport and storage. Capral Ltd. has developed a concept for packaging aluminum extrusion products utilizing prefabricated plastic cleats. Dependent on the length of packaged product, there would be a number of top and bottom cleat sets. As there is positive location of the side cleats the damage due to loose cleats should be eliminated and even after strap removal the pack will hold its integrity, preventing the material from spilling. Because standard cleats can be utilized, high reusability rate can be achieved.

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VA106

3D-Extrusion Applications and Customer Values: Saving Weight, Elimination Machining, Optimizing Products

Mark Jansson Kragh, Arsizio AB, Sweden

Earlier it was impossible to extrude a topology optimized profile or a profile with "3D-features" –it demanded heavy costs for machining, logistics and material waste to give a profile the performance, or design the customer really wanted. As a result many profiles are compromises with same material thickness all the way –even though the customer/application would be better off with varied thickness and design or performance enhancing 3D-features. 3D-iExtrusion can multiply process value in existing extrusion lines at the same times as the customers in different segments can get what they want: an optimized profile/product for their application, with completely new design possibilities, higher application performance & superior environmental performance at a low price thanks to reduced or eliminated machining & material waste –all in existing aluminum extrusion lines.

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VA134

Base Metal Microstructural Considerations for Anodizing Aluminum Extrusions

Jude M. Runge, CompCote International, Inc., USA

Streaks, pits, grain boundary relief, and haze are examples of some of the most common defects developed on extrusion surfaces by anodizing. Often, the defects are not visible in the as-manufactured condition, which makes it difficult to ascertain the root cause for the observed phenomena. In many cases, the source can be found within the substrate microstructure, which in turn can point to variations in the manufacturing process. In order to show the intimate relationship between base metal microstructure and anodic oxide appearance and quality, this paper presents data from unrelated studies that targets different alloys and tempers, showing how differences in manufacturing process parameters produce differences in microstructure, which are, in turn, developed by anodizing. By understanding the impact of chemistry, composition, deformation process and thermal history on microstructure, alloy selection, manufacturing and surface finishing can be optimized to yield desired performance and appearance.

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VA136

Anodizing Response in Alluminum Profiles Extruded from Alloys of 6xxx-series at Different Tempers & Study of Different Characteristics     

Mudar AlMekdad, Arif Hussain, and Mansoor Ali Khan, Gulf Extrusions Co. LLC, UAE

Aluminum profiles extruded from AA6060, AA6061, AA6063, AA6005A, AA6082 are subjected to different heat tempers of F, O, T1, T4, T5, and T6, then particularly anodized (Type II anodizing) to 10, 15 and 20 microns. These profiles are then subjected to different sealing rates in order to study the response of anodizing to different alloys of 6xxx series. Various parameters such as metallography , anodized layer hardness measurement--using both horizontal and vertical testing techniques, and variations of the hardness with the temperature of the electrolyte, acid concentration, influence of homogeneity of micro-structure, and current density are studied.aluminum

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VA141

Innovative Anodizing Plant: Low Operational Cost, High Performance

Walter Dalla Barba and Marcello Rossi, Italtecno Srl, Italy

Nowadays, high quality and low operation cost are the keys to success of any type of industry. In particular, an anodizing plant could adopt innovative technologies that allow it to obtain very high performance, which results in very uniform anodizing layers, many colors resistant to strong UV light, anodic layers with high corrosion resistance, not only to acid corrosion but also to alkaline, and requested especially by the automotive industry. Operational costs can be kept much lower than in conventional plants due to specific electronic devices, which can monitor all the energy and chemical wastes. In regards to water saving and waste water treatment, it is possible to reduce to zero or almost zero, the water consumption and zero liquid discharge plants using these devices that are available at affordable investment and operational costs. The innovative patented zero-discharge system is a “revolution” compared to conventional physical chemical systems, and has been particularly designed for the treatment of liquid wastes derived from anodizing plants and powder coating pretreatment. All the above technologies are described in detailed in the paper with pictures and practical examples of industrial applications.

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VA148

Acid Etch: Acid Etch Update and Process Improvements

Linda Newman, Houghton Metal Finishing, USA

Acid etch has been gaining market share in the aluminum anodizing industry over the past 8-10 years. Many anodizing plants have made the switch to the acid etch process; however there are many more uses for this unique finish. This paper will provide in-depth technical details and the latest research and development discoveries on this process. This paper will also discuss process improvements to optimize product consumption, aluminum dissolution, gloss readings and discuss the many advantages of using the acid etch process to the extruder and finisher. New industry uses of the acid etch process will also be discussed.

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VA160

Efficiency of Innovative Borate-Free Cleaners for the Aluminum Industry

Lorenzo Donati and Luca Tomesani, University of Bologna - Department of Industrial Engineering DIN; and Federico Vincenzi and Walter Dalla Barba, Italtecno Srl, Italy

Degreasing products currently on the market to be used prior to anodizing or painting generally contain borate. Borate must be limited in the waste water since in the EU it is no longer permitted in discharged water. The paper analyzes four new borate-free agents (cleaners) able to remove any grease or solid soils adsorbed or chemically bonded to the surface of the parts. Different borate-free formulations (two proposed by Italtecno MG19 NB2 and MG19 NB3 and two available on the market) were tested and investigated evaluating the cleaning efficiency compared to formulation actually in use in Aeronatics containing borates and also evaluating the impact in terms of corrosion or damage of these new formulations on the aluminum alloys used in the tests. The aluminum alloys under testing were 2024 clad and unclad typically used in aeronautical applications. The paper summarizes the main findings of the project BFCleaner (EU call SP1 - JTI - CLEAN SKY - 2011 - 01) funded by the European Community within the Joint Technology Initiative ”Clean Sky”.

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VA172

Surface Topography of Aluminum Extrusions after Caustic and Acid Etching and Its Implication for Streaking Defects

Xinquan Zhang, Rio Tinto Aluminium, and Natalia Danilova, Queensland University of Technology, Australia

Caustic or acid etching is used for pretreatment of aluminum extrusions in an anodizing line. Apart from surface cleaning, it removes die lines, pickups and rough surface patches on the extruded profiles. Furthermore, it reduces the gloss of the substrate and thus helps to obtain consistent surface appearance after anodizing. The current work examines commercially anodized extrusions with a focus on the comparison of surface topography of caustic-etched and acid-etched extrusions. Various types of streaking defects on anodized extrusions are investigated, aiming to illustrate the difference in defect formation mechanism due to different etching methods employed. The study found that acid etching can significantly reduce the occurrence of compositional and die streaks. However, certain types of streaking defects may still be visible on the anodized extrusions. The root causes of these streaking defects are discussed and preventive measures are recommended.

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VA186

Thermal Break Solutions for the Aluminum Fenestration Industry

Marco Morganti and Giovanni Barbareschi, FOM Industrie Srl, Italy

Most of the industrialized countries have placed regulations that impose a certain level of thermal insulation in the Building Envelope Systems. Due to International Regulations that are going to be implemented, development countries will soon have to follow this trend.
The paper initially presents the use of Thermal Break Aluminum extrusions in the manufacturing of windows, doors and curtain walls systems, its development through the years and different Thermal Break solutions used in various part of the world. Then it describes the various equipments that are necessary to implement for the assembly of Thermal Break Aluminum extrusions. Finally various types of thermal break assembly lines and plants with different productivity rates and different levels of automation are presented.

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VA189

Comparison of Extruded AA 6063 T6 and T7 Properties

Frank F. Kraft, Timothy J. Cyders, Muhammad Ali, and Eboreime Ohioma, Ohio University; Adam J. Cramlet, Alexandria Industries; Richard Dickson and Eskild Hoff, Hydro Aluminum Metals, USA, USA

Extruded aluminum alloys, such as AA6063, are increasingly being used for structural application in automotive vehicles. Requirements generally include a combination of sufficient strength and ductility to meet performance criteria such as crashworthiness. To that end, AA6063 is often used in the T7 (overaged) condition, over the standard T6 temper. This paper provides a quantitative assessment and comparison of the mechanical properties and microstructure of a standard rectangular profile from AA 6063 in the T6 and T7 conditions. Mechanical properties are determined using basic tensile testing. The characterization of mechanical properties focuses on basic strength and ductility properties, true stress/strain behavior to necking, plastic anisotropy, strain rate sensitivity, and post instability ductility to fracture. A basic microstructural analysis is provided and it is associated with the material behavior. Implications to structural requirements are discussed.

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VA196

Anodizing as Pre-Treatment for Powder Coating: Technical and Environmental Advances

Alberto Abad Fuentes, Alvarez-Schaer, S.A., Spain

Pre-treatment of extruded aluminum for organic coating has been traditionally carried out with chromium (VI) salts. However, current restrictions in the industrial use of certain carcinogenic and mutagenic substances have led to a progressive substitution of hexavalent chromium salts as pre-treatment for organic coatings. Anodizing stands out among the available alternatives. As we will show in this paper the use of sulfuric acid anodizing (Type II) as pre-treatment for power coating gives better corrosion resistance than the use of toxic chromic salts.

The influence of anodizing parameters on the later adhesion of powder coatings and the protection against corrosion has been studied. We found out that the last conditioning stage has a very important influence in the later performance of the combined coating. Currently the conditioning process is carried out in hot water to remove from the anodic coating contaminants coming from the anodizing step. The temperature of this stage must be high enough to assure that all residues will be removed but without starting a sealing process that would compromise the adhesion of the anodizing coating to the powder coating. Alvarez-Schaer has developed an environmentally friendly process to clean the anodic pores with excellent adhesion and corrosion results.

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VA202

TriPlex - An Aluminum Oxide Thermal Variable Process

Walt Ahland , Lights Camera Action, LLC, USA

MIL-A-8625 is the anodizing model specified for military and aerospace products, covering six types and two classes of anodizing. The TriPlex process is described to enhance the anodizing process, working with certified anodizing lines and exceeding MIL-A-8625 specifications: impact resistant – parabolic impact test in excess of 150PSI without fracture; corrosion resistant – 16,000 hours in salt spray chamber; abrasion resistant – 94,000 cycles, Taber Abrasion test; malleable – bend 180 degrees without fracturing; and acid resistant – 48 hours without failure in Hydrochloric Acid test. This process works on all aluminum, from casting/forging to 8xxx-series grade, and is used commercially in the LED and aerospace industries.

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