Chemistry And The Metal Fabricator | RMT

Real World Application

Like most kids, you probably hated taking chemistry in high school. It was yet another class, like math and English, where you were required to memorize things that you were sure you’d have no need for in the post-high school “real world.” If you could have just taken shop classes and P.E. all day long, life would have seemed perfect.

Yet once you embarked in a career in metal fabrication, you started to discover that some of those lessons you learned about geometry and reading comprehension came in very useful. And though you may never have taken the time to think about it, chemistry plays a pivotal role in every aspect of the metal fabrication you perform today.

The Fundamental Fabrication Science

Chemistry is the fundamental science that underpins various metallurgic processes, from the extraction of raw materials to the shaping of final products:

Extraction. Most metals occur naturally as ores, which are compounds composed of metal elements chemically bonded with other elements. The extraction process often involves various chemical reactions to isolate the desired metal from its ore. For instance, in the extraction of iron from iron ore (hematite or magnetite), chemical reactions such as reduction using carbon monoxide or hydrogen are employed to separate the iron from oxygen.

Alloying. Pure metals often lack the desired mechanical, chemical, or physical properties required for specific applications. To enhance these properties, metals are often alloyed with other elements. Alloying involves mixing a base metal with one or more additional elements to create a material with improved characteristics. Chemistry plays a critical role in determining the composition of alloys and understanding how the addition of different elements influences their properties. For example, the addition of carbon to iron forms steel, which exhibits greater strength and hardness compared to pure iron due to the formation of iron carbide.

Corrosion Resistance. Corrosion is a significant concern in metal fabrication, particularly for components exposed to harsh environments or corrosive substances. Chemistry provides insights into the mechanisms of corrosion and strategies to mitigate its effects. Surface treatments such as plating, painting, or applying corrosion-resistant coatings rely on chemical principles to create barriers that protect metals from corrosive agents. Additionally, the development of corrosion-resistant alloys with specific compositions is guided by an understanding of how different elements interact with corrosive environments.

Heat Treatment. A crucial process in metal fabrication, heat treatment alters the microstructure of metals to achieve desired mechanical properties. Heating and cooling metals in a controlled manner can modify their hardness, strength, toughness, and other characteristics. Chemical reactions occurring during heat treatment, such as phase transformations and diffusion, dictate the resulting properties of the material. For example, annealing involves heating a metal to a specific temperature and then slowly cooling it to relieve internal stresses and improve ductility, a process governed by the principles of solid-state diffusion.

Welding. Welding and joining techniques are fundamental to metal fabrication, allowing the assembly of complex structures from individual metal components. These processes rely on the application of heat and/or pressure to fuse or mechanically join metals together. Chemistry plays a crucial role in welding processes, influencing factors such as the choice of welding consumables, fluxes, shielding gases, and the formation of intermetallic compounds at weld interfaces. Understanding the chemistry of welding helps optimize process parameters to ensure strong, durable joints while minimizing defects such as porosity or cracking.

Chemistry and the Future of Fabrication

Many fabrication processes generate waste products, emissions, or consume significant amounts of energy and resources. Chemistry provides the framework for developing sustainable practices, including waste treatment, recycling, and the development of cleaner production technologies. Green chemistry principles are now guiding efforts to minimize the environmental footprint of metal fabrication by reducing hazardous chemicals, energy consumption, and waste generation throughout the entire lifecycle of metal products.

As a metal fabricator, you should continue to increase your knowledge base by learning about the chemical composition of the different metals you fabricate. Even if you say, “Well, I really only work with steel,” keep in mind that not only are there four major groups of steel (carbon steels, alloy steels, stainless steels, and tool steels), but there are also over 3,500 different grades of steel, each differentiated by the quantity of carbon and other alloying elements in it, as well as how it is processed. The more you understand about the composition of metal, the better prepared you are to work with it in an efficient way.

By understanding the underlying chemical principles of metalworking, metallurgists can optimize processes, develop innovative materials, and mitigate environmental impacts. The synergy between chemistry and the metalworking industry not only drives technological advancements but also fosters sustainable practices essential for the future of manufacturing. As the field continues to evolve, the important connection between chemistry and metal fabrication will only grow, shaping the way we design, produce, and utilize metal-based products in a rapidly changing world.

Source link