Web Content Filters
The theme for the November 2018 conference was "Failures Worth Analyzing." While technology advances fast and the market demands the latest and the greatest, successful companies strive to stay competitive and remain profitable.
Authors: John Weritz
This article describes the ANSI H35.1 designation system, which is widely used to classify wrought and cast aluminum alloys. The ANSI standard uses a four-digit numbering system to identify alloying elements, compositional modifications, purity levels, and product types. It also uses a multicharacter code to convey process-related details on heat treating, hardening, cooling, cold working, and other stabilization treatments. The article includes several large tables that provide extensive information on aluminum alloy and temper designations and how they correspond to critical mechanical properties as well as other designation systems.
Authors: Junsheng Wang
This article focuses on the effects of alloying and the metallurgical factors on phase constituents, structure, and properties of aluminum alloys. Effects from different combinations of alloying elements are described in terms of relevant alloy phase diagrams. The article addresses the underlying alloying and structural aspects that affect the properties and possible processing routes of aluminum alloys. It provides information on the heat treatment effects on the physical properties of aluminum alloys and the microstructural effects on the fatigue and fracture of aluminum alloys. The important alloying elements and impurities are listed alphabetically as a concise review of major effects.
Authors: J. Gilbert Kaufman
This article reviews the properties of pure aluminum in purities from 99.99 percent through commercial purity, 99.00 percent. The mechanical properties of aluminum are discussed in terms of tensile properties, stress-strain relationships, and creep. The article also reviews the physical properties of aluminum, such as atomic structure and nuclear properties, atomic spectrum, crystal structure, density, thermal expansion, and thermal conductivity. It discusses the chemical properties of aluminum and presents a summary tabulation of the mechanical strength, ductility, and hardness of pure aluminum.
Authors: Erik Miller and Shuang Liu,
This article provides a comparison of the energy consumptions and efficiencies of laser beam welding (LBW) with other major welding processes. It discusses the two modes of laser welding. The article reviews the factors of process selection and procedure development for laser welding. The factors include power density, interaction time, laser beam power, laser beam diameter, laser beam spatial distribution, absorptivity, traverse speed, laser welding efficiency, and plasma suppression and shielding gas. The article concludes with a discussion on laser cutting, laser roll welding, and hybrid laser welding.
Authors: D.J. Spinella
This article discusses the general factors affecting resistance welding: electrical and thermal conductivities, rising temperature, plastic range, shrinkage, and surface oxide. It reviews the weldability of base materials such as Alclad alloys and aluminum metal-matrix composites. The article describes the joint design and welding procedures for resistance spot welding, as well as the joint type, equipment, and welding procedures for seam and roll spot welding. It concludes with information on flash welding, high-frequency welding, and cross-wire welding.
Authors: D.P. Sekulic
This article discusses the key physical phenomena in aluminum brazing and the materials for aluminum brazing, including base metals, filler metals, brazing sheet, and brazing flux. It describes various aluminum brazing methods as well as discussing some alternate brazing methods. The article reviews the brazing of aluminum to ferrous alloys, aluminum to copper, and aluminum to other nonferrous metals. It also discusses post-braze processes in terms of post-braze heat treatment and finishing. The article concludes with information on the safety precautions considered in brazing aluminum alloys.
Authors: Richard Martukanitz
This article schematically illustrates the keyhole instability in LBW and describes the process details of LSW. Representative macrographs of butt, lap, and fillet welds produced using the LBW and LSW processes are presented. The article discusses the laser welding technologies having a large impact on the ability to apply LSW in production. It concludes with information on the industrial applications of LSW.
Authors: Kevin Colligan
This article focuses on friction stir welding (FSW), where frictional heating and displacement of the plastic material occurs by a rapidly rotating tool traversing the weld joint. The article describes the aspects of how FSW actually accomplishes sound joints in metals without melting them. It discusses the FSW process variations and the practical aspects of heat generation. The article provides information on the effect of welding on material properties and typical alloys in FSW applications. The alloys include 6061 aluminum, 5083 aluminum, 2xxx aluminum, and 7xxx aluminum alloys. The article concludes with a discussion on FSW equipment.