Steel is all around you. From building infrastructure to surgical tools, you can understand a lot if you learn about the broad range of purposes for steel. The properties of steel emerge from how it's built for these purposes, and the specific composition can have a big impact on the mass and, consequently, the weight of steel. The best way to calculate the mass of steel and it's weight is based on it's density and the volume you have.
Steel Weight by Volume
You can calculate the weight of steel by using the weight equation W = m_g for the weight _W in newtons, mass m in kilograms and gravitational acceleration constant 9.8 m/s2. The mass of an object measures the amount of matter an object contains while weight is the force that the object exerts on the Earth due to gravity. Using the weight equation, if you know the mass of an object, you can use that to calculate weight. One newton is equal to about 0.224809 pounds of force.
You can also use steel density to calculate mass. The density of an object is mass divided by volume, so you can multiply density by volume to get mass. Make sure to keep track of what the units are for these calculations. If you have 10 cm3 of steel with a density of 7.85 g/cm3, the mass would be 78.5 g or 0.0785 kg. You can convert mass to weight by multiplying it by 9.8 m/s2 to get 0.77 newtons of steel.
You can also determine the steel density using its specific gravity. The specific gravity or relative density is the ratio of a physical material's density to that of water. The specific gravity of carbon-based steel is 7.8. This number has no units because it is a ratio of one density to another density: in other words, the units used in the density for both steel and water cancel out.
Different Steel Density Values
Steel density depends on how its made. Different methods of measuring steel density can means you can figure out which one best suits your needs.
Steel density varies on how the steel is made. Metal steel used for tools is 7.715 g/cm3, metal wrought is 7.75 g/cm3, carbon-based steel tools are 7.82 g/cm3, metal pure iron is 7.86 g/cm3 and metal soft steel (with very little carbon) is 7.87 g/cm3. These different steel density values suit their various purposes.
Sometimes the weight of steel is given relative to the thickness of steel. 40.80 lb/ft2 of steel has a thickness of 1 inch, according to the Engineering Toolbox. Multiply this weight in pounds-per-foot-squared by how many feet-squared area of steel you have to determine the weight in pounds.
Types of Steel
The four primary ways of dividing various types of steel are carbon steel, alloy steel stainless steel and tool steel with different steel properties. Carbon steels are hard and brittle for use in manufacturing machines. Alloy steels have other elements like vanadium, molybdenum and copper so they can be used in knives and gears.
You can use high-strength low alloy (HSLA) steel in steel structures as well as pipelines for gas and oil. These types are actually a kind of carbon steel with other elements added to increase toughness, corrosion resistance and responsiveness to heat. Stainless steel products contain trace elements of chromium and nickel to let them retain their color and structure in pipes, surgical tools, construction. They withstand corrosion and high temperatures.
Tool steels are made with tungsten and molybdenum, and are much, much harder. They're used for tools that cut metals. Steel that is made with high amounts of carbon is generally used in automobile manufacturing. Though these different types of steels have different steel properties, you can measure their weight and mass just the same using density and volume.
- The Physics Factbook: Density Of Steel
- SchoolScience: Steel for Many Purposes
- LinkedIn: 21 Chemical Elements and Effects on Steel Mechanical Properties
- Metal Supermarkets: What is HSLA Steel?
- Pennsylvania Scale Company: Weighing Systems: Mild Steel or Stainless Steel?
- Industrial Metal Supply Co: Carbon Steel vs Stainless Steel
About the Author
S. Hussain Ather is a Master's student in Science Communications the University of California, Santa Cruz. After studying physics and philosophy as an undergraduate at Indiana University-Bloomington, he worked as a scientist at the National Institutes of Health for two years. He primarily performs research in and write about neuroscience and philosophy, however, his interests span ethics, policy, and other areas relevant to science.