Understanding the Atomic Structure of Steel

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<h3>Understanding the Atomic Structure of Steel</h3>

Steel is a metal alloy widely used in construction owing to its strength, affordability and hardness. Its various forms consist almost entirely of iron, but also contain the elements carbon, manganese, phosphorous, sulfur, silicon, and sometimes nickel and chromium. Steel takes advantage of the highly stable atomic lattice structure of iron, with an important twist.

The Crystal Lattice

Iron, in its solid form, assumes a crystalline structure, meaning simply that the iron atoms are arranged in a regular, repeating pattern called a lattice. Many lattices exist in nature, but iron comes in one of two forms — the body-centered cube, which exists at higher temperatures, and the face-centered cube, its room-temperature form.

The Role of Carbon

Adding carbon to liquid iron — typically in amounts ranging from .035% to 3.5% by mass — changes what happens when the mixture cools to its freezing point (roughly 1,500°C). Instead of going from being a body-centered lattice to becoming a face-centered lattice, the iron atoms settle directly into the latter. At the same time, the carbon atoms lodge in the center of these cubes. This ultimately accounts for the greater durability of steel compared to pure iron.



Dave Pennells

By Dave Pennells

Dave Pennells, MS, has contributed his expertise as a career consultant and training specialist across various fields for over 15 years. At City University of Seattle, he offers personal career counseling and conducts workshops focused on practical job search techniques, resume creation, and interview skills. With a Master of Science in Counseling, Pennells specializes in career consulting, conducting career assessments, guiding career transitions, and providing outplacement services. Her professional experience spans multiple sectors, including banking, retail, airlines, non-profit organizations, and the aerospace industry. Additionally, since 2001, he has been actively involved with the Career Development Association of Australia.