What is Cast Iron?
Cast iron is a type of ferrous metal, meaning that it contains iron. The carbon percentage in cast iron can range anywhere from 2% to 6%, with the majority of cast irons containing around 3- 4%. This makes cast iron more brittle with carbon rich phases than other types of ferrous metals, like steel, which contain a carbon percentage of less than 2%. Cast iron is often used for cookware because it can withstand high temperatures without corroding or warping.
Cast Iron mainly contain Fe, Silicon, Manganese, Carbon as main alloying elements. During solidification, based on the cooling rate Cast Iron either solidify as Iron-Cementite (Fe-Fe3C) or Iron-Graphite (Fe-Gr) systems.
Types of Cast Iron
Cast iron is a versatile material that has been used for centuries in a variety of applications. There are several different types of cast iron, each with its own unique characteristics. The main types of Cast Iron are:
- White Cast Iron
- Malleable Cast Iron
- Ductile Cast Iron (Spheroidal Graphite Cast Iron)
- Grey Cast Iron
- Mottled Iron
- Austempered Ductile Cast Iron
Here is a look at the three most common types Cast Iron Chemical Composition before you learn about them in details.
Gray Cast Iron
Gray Cast Iron is the most common type of cast iron. It is strong, durable, and inexpensive, making it a popular choice for many applications. It is used for machining parts, pump casing, engineering valves, structures, and other cast parts.
Gray cast iron is also very brittle with gray fracture surface, so it should not be used in applications where toughness is required. Gray Cast Iron contains 2.5%- 4% Carbon, 1-3% Silicon with added Manganese.
One most common Gray Cast Iron material specification is A48 that cover different strength cast iron materials. Gray Cast Iron has good machinability, high wear resistance & compressive strength and good damping capacity.
Malleable Cast Iron
Malleable cast iron is a type of cast iron that has been heat treated in order to make it more flexible. To make Malleable Cast Iron, white cast iron is subjected to heat treatment that makes it similar to ductile cast iron with good strength & toughness.
This type of Cast Iron responds good to heat treatment to alter its properties similar to medium carbon steel. Malleable cast iron is also used for making pipe fittings, valves, and other types of hardware. Malleable Cast Iron is costlier than Ductile Cast Iron.
Two main types of Malleable Cast Iron are:
- Blackheart Cast Iron and
- Whiteheart Cast Iron.
The material specifications for Malleable Cast Iron are ASTM A47, ASTM A338, A 197, A602, & SAE J158, etc. They are used in automotive industries, railroad, machine parts and hand tools.
White Cast Iron
White cast iron is similar to gray cast iron but has a higher melting point and greater resistance to wear and tear. It exhibits white color appearance when fracture as fracture take place in the iron-carbide plates. It is commonly used in bearings and other components that require durability.
Ductile Cast Iron
Ductile cast iron (also called Nodular Iron or Spheroidal Graphite-SG Cast Iron) is the strongest type of cast iron. It has a high resistance to fracture and can withstand high levels of stress without breaking. This means ductile irons has high strength, high elongation and toughness compared to other types of Cast Irons (E.g., Malleable Iron or Gray Cast Iron) Ductile iron contains small nodules of graphite in its microstructure.
The material specification for Ductile Cast Iron are ASTM A395, A476, A536, SAE J434, ISO 1083, and SAE AMS 5315C, etc.
Ductile Cast Iron are used for applications that require high strength, toughness and ductility with good machinability with low overall cost for the material. They are used in automotive, agricultures, pumps parts and many more areas.
Cast Iron Vs Wrought Iron
Cast iron and wrought iron are both types of metal, but they have different properties. Cast iron is a brittle, grayish-white metal that is very heavy and hard. Wrought iron is a tough, malleable metal that is less heavy than cast iron and has a silvery color.
Cast iron is made by melting pig iron and adding other metals to it. Wrought iron is made by heating wrought iron ore in a furnace until it liquefies and then cooling it in a mould.
Cast iron can be used to make products such as pump casing, cookware, pipes, and furniture. Wrought iron (melting point of Wrought Iron is 1538°C (2800°F) can be used to make products that need to withstand high temperatures because it melts at a high temperature than cast iron (melting point of Cast Iron is 1204°C (2200°F).
Cast iron and wrought iron are both types of ferrous metals, meaning they contain iron. Cast iron is made by melting pig iron and other alloys in a blast furnace and pouring the liquid into a mold. Wrought iron is made by heating pig iron until it becomes malleable enough to be worked with a hammer.
The two metals have different properties. Cast iron is brittle and weak, while wrought iron is tough and strong. This is because cast iron contains more carbon than wrought iron. The carbon makes the metal more brittle and less ductile.
Cast irons are usually used for making heavy objects such as statues, pipes, or cookware because they are inexpensive and durable. Wrought irons are usually used for making objects that need to be strong, such as tool handles, fences, or rods.
Cast Iron Vs Ductile Cast Iron
Cast iron is a type of metal that has been used for centuries. It is made by melting pig iron and adding carbon. The carbon makes the metal harder and stronger. Cast iron can be machined, but it is not very strong.
Ductile cast iron (also called Nodular Iron or Spheroidal Graphite-SG Cast Iron) is the strongest type of cast iron. It has a high resistance to fracture and can withstand high levels of stress without breaking.
This means ductile irons has high strength, high elongation and toughness compared to other types of Cast Irons (E.g., Malleable Iron or Gray Cast Iron) Ductile iron contains small nodules of graphite in its microstructure.
The material specification for Ductile Cast Iron are ASTM A395, A476, A536, SAE J434, ISO 1083, and SAE AMS 5315C, etc.
Ductile Cast Iron are used for applications that require high strength, toughness and ductility with good machinability with low overall cost for the material. They are used in automotive, agricultures, pumps parts and many more areas.
Cast Iron Vs Enameled Cast Iron
Cast iron cookware is a classic kitchen standby that’s been around for centuries. It’s durable, affordable, and versatile, making it a popular choice for everything from weeknight meals to Thanksgiving dinner. But there’s a newer option on the market that might have you wondering if cast iron is really the best choice: enameled cast iron.
So, what’s the difference between cast iron and enameled cast iron? Cast iron is simply an uncoated metal cookware made from molten iron that’s poured into a mold. Enameled cast iron, on the other hand, has a glass or porcelain coating that not only looks nicer but also makes it easier to clean.
Enameled cast iron also has some other key benefits. First, it’s non-stick, so you don’t have to worry about food sticking and creating a mess.
Enameled cast iron is made from cast iron that has been coated with a porcelain enamel.
The biggest difference between cast iron and enameled cast iron is the durability of the coating. The enamel on enameled cast iron is much more durable than seasoning on cast iron, so it is less likely to chip or flake off. Enameled cast iron also has a slightly different texture than regular cast iron, which some people prefer.
Cast Iron Vs Carbon Steel
Cast iron and carbon steel are the two most common types of steel. Cast iron is made up of mostly iron and a high amount of carbon, while carbon steel has more less carbon and more iron compared to Cast Iron. Carbon steel is tougher and stronger than cast iron while Cast Iron is more brittle. Cast iron is not as strong as carbon steel, but it is more resistant to wear and tear with higher compressive strength.
Cast iron is made of pig iron and a high amount of carbon. The carbon content ranges from 2% to 4%. Carbon steel is made from pig iron by further processing it in the mill to refine & reduce the level of Carbon, Manganese, Sulfur & Phosphorus with some other alloying elements.
The carbon content in carbon steel is usually between 0.1% and 1.5% (There are different types of Carbon Steel based on Carbon percentage- E.g., low carbon steel, medium carbon steel & High carbon steel).
Carbon steel is malleable metal while Cast Iron is brittle. This means that they can be easily shaped by hammering or pressing them. Cast iron is not tough, meaning that it cannot withstand blows with hammer and will break. Carbon steel is tougher than cast iron, but not as tough as stainless steel.
Cast iron has a lower melting point than carbon steel. This means that it can be melted down and poured into molds at a lower temperature than carbon steel.
- Cast iron and carbon steel are both types of metal, but they have some key differences.
- Cast iron is made up of mostly iron and has a very high carbon content, while carbon steel is made up of mostly Iron and has a lower carbon content.
- This makes cast iron much harder and more brittle than carbon steel.
- Cast iron also has a much lower melting point than carbon steel, meaning it cannot withstand higher temperatures compared to Carbon Steel.
- Cast Iron is also more corrosion-resistant than Carbon steel, making it better suited for use in outdoor applications.
- Cast Iron posses higher dampening capacity & compressive strength than Carbon steel. But carbon steel has high yield & tensile strength compared to Cast Iron.
Cast Iron Versus Cast Aluminum
The debate of cast iron versus cast aluminum cookware is one that has been around for many years. Both have their own unique benefits and drawbacks, but which one is the best for you? Here are five differences between cast iron and cast aluminum cookware:
- Weight: Cast iron cookware is heavier than aluminum cookware. This can be a pro or a con, depending on your preferences. Heavier cookware can be more difficult to move around, but it also tends to distribute heat more evenly than aluminum cookware.
- Heat Transfer: Cast iron can take longer to heat up than aluminum, but it also retains heat better once it is hot. This means that you can usually get your food to a desired temperature and then keep it there without having to worry about it cooling down too much.
- Corrosion Resistance: Cast Aluminum has higher corrosion resistance compared to Cast Iron.
- Appearance – Cast aluminum typically has a more polished appearance than cast iron. This can be an important consideration for certain applications, such as decorative items or products that will be visible to consumers.
- Strength – Cast aluminum is stronger than cast iron, making it a better choice for products that need to be durable.
Cast iron is a material that has been used for centuries in a variety of applications. It is strong, durable, and relatively inexpensive compared to other materials. Cast aluminum is a newer material that has begun to replace cast iron in some applications. It is lighter and stronger than cast iron, but also more expensive.
Cast Iron Vs Acrylic Tub
Here are top 6 differences between cast iron and acrylic tubs:
- Cast iron tubs are often considered more luxurious and have a classic look that many homeowners love.
- However, acrylic tubs are becoming more popular because they can be more affordable and easier to care for.
- Strength: Cast iron tubs are stronger and can hold up to heavier use than acrylic tubs.
- Temperature retention: Cast iron tubs retain heat better than acrylic tubs, making them a popular choice for soaking.
- Cost: Cast iron tubs can be more expensive than acrylic tubs, although this varies depending on the style and brand.
- Weight: Cast iron tubs are heavier than acrylic tubs, which can make them harder to move around or install on your own.
Cast Iron vs Stainless Steel
Cast iron and stainless steel are two of the most popular materials but has their distinct unique properties. Though they have some similarities, there are also some key differences between them. Here are five differences between cast iron and stainless-steel materials:
- Cast iron (Cast Iron Density is 7.2 g/cm3) is lighter than stainless steel (Stainless Steel Density is 7.9 g/cm3). This can be a good or bad thing, depending on your preference.
- Cast iron heats up slowly but retains heat well, while stainless steel heats up quickly but doesn’t retain heat as well. Stainless steel has low thermal conductivity with higher expansion, which can result in more distortion.
- Cast iron has a natural non-stick coating that builds up over time, while stainless steel does not have this coating and must be treated with a non-stick agent like oil or butter to prevent sticking if used for cookware applications.
- Cast iron can rust if not properly cared for, while stainless steel will not rust easily as it has very high corrosion resistance.
- Cast Iron is much cheaper than stainless steel. Stainless steel is alloyed with costly elements such as Nickel, Chromium and Molybdenum, making it one of costly engineering material.