AWS WHB-5.9

HARDCOPY ONLY

INTRODUCTION

Aluminum (Al), one of the most plentiful elements mined from theearth, is found in its oxidized form in bauxite, which, whenrefined, yields 40% to 60% alumina (aluminum oxide,Al₂O₃). The aluminum is separated from theoxygen using the Hall-Héroult electrolysis process, which wasinvented in 1886. This process made possible the production ofaluminum on an industrial scale, increasing availability anddrastically reducing the cost from the prevalent price of $600/lbin the years before. Aluminum usage in the world has grownexponentially since then, driven by the development of new joiningtechnology and new applications.

Aluminum is highly ranked among the most useful metals known tomanufacturers and fabricators. The strength of some aluminum alloysexceeds that of mild steel; aluminum can be cast, rolled, stamped,drawn, spun, stretched, or roll-formed. It can be hammered, forged,or machined with ease and speed, or extruded into a wide variety ofshapes; then it can be given an equally wide variety of mechanical,electromechanical, chemical, or paint finishes.

Aluminum retains good ductility at subzero temperatures, ishighly resistant to corrosion, and is not toxic. It has goodelectrical and thermal conductivity, is highly reflective of heatand light, and is nonsparking and nonmagnetic.

The properties of aluminum and aluminum alloys are valuable forcritical applications in the space and aircraft, marine, andautomotive industries; for structural applications; for vessels andstorage tanks; and are also vital for countless consumer products.Processes to weld aluminum continue to improve and have contributedto the widespread use of this remarkable material.

Most of the common joining methods—welding, brazing, soldering,adhesive bonding, and mechanical fastening—can be used to joinaluminum.¹ All processes, except mechanical fastening,are discussed in this chapter; a brief section on aluminum cuttingis also included.^{2, 3}

1. For information on welding, brazing, soldering, and adhesivebonding processes, refer to American Welding Society (AWS) WeldingHandbook Committee, 2004, Welding Handbook, 9th ed., ed.A. O’Brien, and Welding Processes, vol. 2, Part 1, ed. A.O’Brien, and Welding Processes, vol. 3, Part 2, 2007, ed.A. O’Brien and C. Guzman, Miami: American Welding Society. Refer toAppendix B of this volume for a list of chapter contents for thefive volumes of Welding Handbook, 9th ed.

2. At the time this chapter was prepared, the referenced codesand other standards were valid. If a code or other standard iscited without a date of publication, it is understood that thelatest edition of the document referred to applies. If a code orother standard is cited with the date of publication, the citationrefers to that edition only, and it is understood that any futurerevisions or amendments to the code are not included; however, ascodes and standards undergo frequent revision, the reader mustconsult the most recent edition.

3. Welding terms and definitions used throughout this chapterare from American Welding Society (AWS) Committee on Definitionsand Symbols, 2010, Standard Welding Terms and Definitions,AWS A3.0M/A3.0:2010, Miami: American Welding Society.

Edition:

9

Published:

01/01/2015

Number of Pages:

752