Iron, steel, and cast iron are three widely used materials that make up many of the tools. There are many differences between them and many people mistake the three points but they are not all the same.
Cast iron and steel are iron-based alloys, the only difference is the amount of carbon used in each. If you notice, many kitchen utensils are made of iron. Cast iron is very soft and cost-effective and is almost indestructible for everything.
The main difference between iron and cast iron is their carbon content. Cast iron contains more than 2% carbon, while many steel alloys contain less than 1% carbon. Before discussing the difference between steel and cast iron, it is best to consider the common properties of both metals:
Common features of steel and cast iron
hardness
Strength/Rigidity
plasticity
toughness (toughness is a combination of formability and power)
You might think that cast iron is made of pure iron, but it’s not! Cast iron is actually an iron and carbon alloy, just like steel; The difference is that cast iron has a higher carbon content. While steel does not require more than 2% carbon, cast iron usually contains 2% to 3.5% carbon. Silicon is another alloying element found in cast iron with a purity of about 1-3%.
The presence of these different elements affects the color and quality of the produced cast iron. The amount of carbon makes cast iron more brittle than steel. Since cast iron is a weak conductor, it keeps heat for a long time.
There are different kinds of cast iron and we will discuss each of them below:
gray cast iron
The shrinkage and porosity of the cast iron is small. This cast iron is the most widely used type of cast iron based on weight, which has a high thermal conductivity and is ideal for baking containers. This cast is softer than cast iron, while its material is hard and brittle.
Gray cast iron is usually used to make the following:
Car base
motor block
motor housing
cast iron tubes
Gear
hard cast iron
The process of making hard cast iron to heat the cast iron and then quickly cool its outer surface, this makes the iron surface white and its core gray. Hard cast iron, as the name shows, is very resistant, will be worn later, and is often used to build under-bridge pipe.
soft cast iron
Soft cast iron is often used for making small appliances such as door and window fittings, locks, keys and even valve. To increase the cast iron hammer and more resistance to it, the white and semi-gray casting is heated by a number of iron ore fins, causing some carbon in it to be lost in the process, burning and softening.
Sefid Cast
Cast iron production process is a method commonly used for making small tools. White cast iron is produced at high speed from pig iron. This color is white because its carbon is not converted to graphite in fast cooling and its color remains bright (white silver).
What is worth noting here is that cast iron is brittle in many applications, this material has very low silicon content and its material is somewhat harsh and brittle.
What is steel?
Steel is an iron alloy that is primarily iron and carbon. Many people think steel is a metal, but it’s not. Although this material has similar properties to metals, it is technically classified as an alloy.
Steel such as cast iron is made of iron and carbon alloy, but it is less than 2% carbon. Stainless steel consists of 1.2% carbon (and chromium to prevent corrosion).
carbon steel is matte, although stainless steel looks slightly shiny. Carbon steel is much harder than stainless steel (usually suitable for making sharp knives), but it is corrugated and rust, while it is not stainless steel.
The main classification of steel based on its carbon content is as follows:
mild steel
The carbon content in mild steel is about 0.2%. Normally mild steel is used for making bolts, barbed wire, tubing, steel plates and even steel beams.
medium steel
The percentage of carbon in average steel is 0.6-0.2 percent. Sinosteel is often used for the construction of rails, boilers and even machines.
hard steel
The percentage of carbon in hard steel is higher than that of conventional and medium steel. The carbon content of this type of steel is about 1.5-0.6%. Hard steel is used to make tools, drills, springs, cutlery, etc.
Cross-sectional steel is an important component of present-day structures. Due to its properties such as high strength and high ductility, it is the most important building materials. The main properties of steel are:
thermal expansion
Portability
Connection
mechanical resistance
It should be noted that the mechanical properties of the steel vary during different thermal and cold processes. Cooling steel can be done slowly in water, oil or in the air using cooling device.
The comparison of cast iron and steel in a single drawing process should be based on several factors. As you know, heat treatment and alloying can greatly alter the properties of metals. To buy one of the two products, it is always best to know each of their characteristics. You can tell the difference between cast iron and steel faster by knowing the following:
Look at the surface of the two metals: Iron, steel and cast iron are easy to detect from appearance! The metal surfaces are dark and shiny gray iron; Cast surfaces are dark, cloudy and colorful.
Molten metal color: Cast steel and iron change color during melting. Knowing this makes it easier to distinguish them from each other. If the color of the molten metal is red, it is iron. On the other hand, if the molten metal is white, it is iron.
Chip test: cast iron is a fragile metal. The potato is crispy and crispy. If a milling or lathe machine is available, we can use part of the metal specimen mechanically.
If the chips are continuous, the metal is cast iron, and if the chips are continuous, it is iron. To perform this test, no milling or a lathe is required. This test can also be done with a sharp pen. If the thin layer is removed from the metal, the strip is removed, the iron metal is removed, if the chips are very well removed. This metal is cast iron.
