Metals make up the majority of the known elements and they are found mostly on the left side of the periodic table. What makes metals special is the way they behave in chemical reactions. They usually lose electrons easily, which means they tend to form positive ions (cations). Because of this property, they readily combine with other elements, especially nonmetals, to create a wide variety of new and useful materials. Depending on how they are combined, you can get materials that are super hard, don’t rust, are really light, or can handle extreme heat. Because of this flexibility, metals play a huge role in almost everything around us – from the technology we use, to the buildings we live in, to everyday items we rely on. For example, steel is not a pure element but an alloy, made mainly of iron mixed with a small amount of carbon. This combination makes steel much stronger and more versatile than pure iron.
Metals are easy to recognize because they are usually shiny, strong, and can be bent, hammered, or stretched into different shapes without breaking. Some of their physical properties are outlined below:
1. Shiny Surface – Metals generally possess a characteristic metallic shine or reflective surface when polished or freshly cut like gold and silver.
2. Malleability – Metals can be hammered, rolled, or pressed into thin sheets without breaking or cracking like aluminum foil.
3. Ductility – Most metals can be drawn into wires, demonstrating their ability to undergo significant plastic deformation like copper wires.
4. Density – Metals typically exhibit high density, making them comparatively heavy for their volume, although exceptions such as aluminum and magnesium exist.
5. Melting and Boiling Points – Metals generally have high melting and boiling points, indicating strong metallic bonding within their structures.
6. Thermal and Electrical Conductivity – Metals are excellent conductors of heat and electricity due to the presence of free-moving electrons (delocalized electrons).
7. Mechanical Strength – Most metals are strong and hard, allowing them to withstand significant forces without deformation.
8. State at Room Temperature – With the exception of mercury, metals exist as solids under standard room temperature and pressure conditions.
Atomic Structure of Metals
The atomic structure of metals is characterized by atoms packed closely together in an ordered, repeating pattern called a crystal lattice. The lattice can take forms such as body-centered cubic (BCC), face-centered cubic (FCC), or hexagonal close-packed (HCP). The outer electrons of metal atoms are delocalized, meaning they are free to move throughout the lattice rather than being bound to individual atoms. This sea of electrons holds the positively charged metal ions together through metallic bonding, giving metals their distinctive properties such as high electrical and thermal conductivity, malleability, ductility, luster, and strength.
Numerical Modeling For Metals
Numerical modeling of metals is essential for predicting how metal components behave under different loads, temperatures and environmental conditions. Metals can show complex behavior including elasticity, plasticity, creep, fatigue and fracture, which are difficult to analyze with simple hand calculations. By creating a numerical model, we can simulate stresses, strains, deformations and failure mechanisms before manufacturing a physical prototype. Now, let’s explore basics of different material models available for metals in FEA.
Linear Elastic Behavior
Linear elastic material behavior is the most basic behavior of metals which refers to the region of deformation in which stress is directly proportional to strain and the material returns to its original shape once the load is removed. This relationship is governed by Hooke’s Law which is expressed as,
σ=E⋅ε
where σ is the stress, E is young’s modulus and ε is the strain in the material when subjected to external load. Linear elasticity assumes that material properties remain constant and is valid only up to the yield point, beyond which plastic deformation begins. In engineering and FEA, it provides a simple yet powerful model for predicting deflections, stresses, and strains under applied loads, as long as the applied stresses remain within the elastic limit. Elastic behavior is modeled in Abaqus by providing the material constants such as Young’s modulus (E) and Poisson’s ratio (ν). Poisson’s ratio describes the lateral contraction that occurs when a material is stretched.
Elastic–Plastic Behavior
Elastic–plastic behavior describes how metals and many other materials respond when the applied stress goes beyond the elastic limit. Once the yield point is reached, the material enters the plastic region where deformation is permanent and irreversible. In this stage, the material can continue to carry increasing loads, but the stress–strain relationship is no longer linear. Depending on the material, it may exhibit strain hardening, where the metal becomes stronger and resists further deformation. When the load is removed after plastic deformation, only the elastic portion of the strain is recovered, while the plastic strain remains. Elastic–plastic behavior is critical to model in engineering and FEA because it governs how metals actually perform under high stresses, ensuring accurate predictions of yielding, residual stresses, and potential failure. To learn more about metal plasticity and available hardening models in Abaqus, please refer to our previous blog here.
Damage & Fracture Behavior
Damage in metals refers to the progressive degradation of their mechanical properties caused by microstructural changes that develop under repeated loading, high stress or harsh environmental conditions. At the microscopic level, damage often starts with the nucleation of tiny voids, micro-cracks or dislocations that gradually grow and link together as the material is strained. Over time these defects accumulate and reduce the metal’s ability to carry loads which leads to softening, loss of stiffness and eventually fracture. To read more about ductile damage model, which is a basic damage model used to define fracture in metals using uniaxial data, please refer to our previous blog here.
Thermal Behavior
Thermal behavior of metals in FEA is typically modeled by solving the heat equation with material properties defined as functions of temperature rather than as fixed room-temperature values. This usually includes temperature-dependent thermal conductivity, specific heat, and density, along with boundary conditions for convection and radiation where surfaces exchange heat with the surroundings. For transient analyses, time-step selection matters because it controls how accurately heating and cooling rates are captured. When metals experience steep thermal gradients, phase changes, or strong nonlinear property variation, those effects should be included explicitly to avoid unrealistic predictions. In coupled thermo-mechanical simulations, the computed temperature field is then mapped into the structural analysis to predict thermal expansion, residual stress, distortion, and, when necessary, thermally driven yielding. To learn more about thermal considerations in FEA, check out our previous blog post on it here.
Creep Behavior
Creep in metals is the slow time-dependent deformation that occurs when a material is subjected to constant load or stress at elevated temperatures. Unlike elastic or plastic deformation, creep develops gradually over time even when the applied stress is well below the yield strength. The process takes place in three stages: primary creep where the deformation rate decreases as the metal work-hardens, secondary creep where a steady constant rate of deformation is observed, and tertiary creep where the deformation accelerates leading to necking and final rupture as voids and cracks grow. Creep is especially important in high-temperature applications such as turbines, boilers and jet engines where long-term exposure to heat and stress can reduce the safety and durability of components. Numerical models provide engineers with a practical means to simulate creep behavior over extended periods within a manageable timeframe and computational resources. To read more about common creep laws that are used in Abaqus for modeling secondary stage creep, please refer to our previous blog here.
Fatigue Life
Fatigue behavior in metals refers to the progressive and localized damage that occurs when a material is subjected to repeated or fluctuating loads even if these loads are below the material’s ultimate tensile strength. Over time tiny cracks can start at stress concentrators such as surface imperfections, notches or inclusions. These cracks gradually grow with each load cycle, weakening the metal until it eventually fractures. Fatigue life is usually divided into three stages: crack initiation, crack propagation and final fracture. The behavior depends on factors such as stress range, load frequency, mean stress, temperature and the presence of corrosive environments. Understanding fatigue is crucial in engineering because many metal components in machines, vehicles and structures fail due to repeated loading rather than a single overload, making accurate prediction essential for safety and durability. To read more about fatigue prediction, please refer to our previous blog here.
Final Thoughts
Metals are fundamental to engineering and everyday life because of their unique combination of strength, conductivity and versatility. Understanding their physical, atomic and mechanical behavior is essential for designing safe and efficient components. Numerical modeling in FEA allows engineers to predict how metals respond under different loads, temperatures and environmental conditions. Material models such as linear elastic, elastic–plastic, damage, creep and fatigue help capture the complex behavior of metals accurately. By using these models, we can optimize designs, prevent failures and ensure the long-term performance of metal structures and components.
We are always here to help, so if you have concerns/questions with material models for metals, don’t hesitate to reach out to our expert team!
