Welds, Adhesives, and Nails

If welds, adhesives, and nails didn’t exist, then the ability to attach two objects to each other would seem miraculous. Without this bonding ability, we wouldn’t be able to construct modern products or appliances, or even be able to inhabit any non-cave dwellings, let alone contemplate great architectural accomplishments like skyscrapers. The genesis of these joining methods spans very far back in history and prehistory, and they are so deeply rooted in our society that we never really stop to admire the components needed to congregate the pieces of our products or the structures around us.

The earliest evidence of anthropogenic bonding of inanimate objects occurred when two stone flakes were sprinkled with birch-bark-tar about 200,000 years ago. Today, there are kinds of glue and tape that can bind basically anything together. Take for example, ISO 10364:2015: Structural adhesives - Determination of the pot life (working life)of multi-component adhesives. The standard provides proper testing procedures to determine the potential lifespan of adhesives that can be used to bond many different materials together. Adhesives can be a reliable way to permanently stick two objects together without requiring difficult attachment procedures.

While welding has its origins far later than adhesives, its original purpose was also completely aesthetic, as opposed to the structural motive that it is often used for today. The earliest welds date back almost 5000 years, when the Ancient Egyptians used them to construct small gold boxes. In our world now, a variety of metals are used for welding and joining. These have applications in building design, bridge construction, and creation of appliances. The American Welding Society (AWS) has published an assortment of standards for welding. These encompass many of these different welding applications.

Nails were first used in a similar time period as welds, possibly being utilized by the Ancient Egyptians as well. Nails have always been in high demand, and were so scarce in pre-1850 America that people would burn down unsound buildings to recover the nails from the ashes. Mass production in manufacturing later sunk the cost of nails, allowing them to be more widely used. Nails differ from welds and adhesives because they are not permanently joining two substances together. Instead, they are fasteners that can be hammered or shot into materials like wood to keep two objects together, or to act as a peg to hang something. Guidelines for the dimensions of steel nails are thoroughly outlined in BS 1202-1:2002: Specification for Steel nails. This can help to ensure that nails are properly crafted so that they can serve their structural purposes.

These different bonding processes are not completely exclusive of one another. Using them together can help provide additional support to any object or structure. AWS A3.0M/A3.0:2010: Standard Welding Terms and Definitions Including Terms for Adhesive Bonding, Brazing, Soldering, Thermal Cutting, and Thermal Spraying is intended to define welding terms but also defines ideas related to adhesive bonding, which can be used in the same procedure.

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