to answer the question of What is the difference between iron, stainless steel, and cast iron we can say that Iron and ferrous metals are the basis for sections, iron, cast iron, and steel, and iron ore are the basis for the manufacture of steel. Pig iron is made by melting iron ore in a smelting furnace, while common iron, cast iron, and steel are made from pig iron, actually, cast iron and steel are alloys of iron. The most widespread of these products are ferrous metals, which account for 95% of the metals produced globally. Iron is a heavy, shiny gray metal extracted from iron ore. Cast iron and steel are also made from pig iron or iron ore, and due to the low price and high resistance of iron compounds, their use in various industries such as buildings, automobiles, and hulls of large ships is affordable and economical. Iron is used in the construction industry in the form of other steel profiles such as steel rods, iron beams, oil paint galvanized boards, corners, gutters, nails, bolts, etc. Iron ore is heated in furnaces to produce iron, steel and cast iron, which are then made into raw materials. Iron ore is a mixture of oxides, mineral salts, limestone, silica, aluminum oxide, etc. of this element. 
There are four types of stone that can be used in an iron furnace. 1- Hydroxide 2- Oxide 3- Carbonate 4- Sulphur Magnetic iron ore with magnetite (68% iron by weight) and red iron ore or hematite (60% by weight of this element) are classified as hydroxides for metal production. Lime to brown iron ore, 50% by weight, classified as oxides. After the iron ore is extracted from the mine, it is crushed in a stone crusher and prepared to enter the furnace by performing special operations. Types of pig iron Carbon is the difference between iron and ferrous metals. The carbon content of iron also determines the properties of iron, steel and cast iron. Pig iron has a high carbon content, so it is brittle and cannot be hammered and rolled as it shatters on impact, and carbon also lowers the metal's melting temperature. There are pig iron, pure iron and ordinary iron, and its carbon content is lower than that of pig iron. Common Iron (Iron) This iron contains about 2% carbon and is obtained by carbonizing pig iron and some iron scrap in the furnace. Its melting temperature is low, around 1130 degrees Celsius. Iron rusts in moist air, so it needs anti-rust treatment. Rusted and it has a protective coating, this metal has many uses in various industries, making industrial machinery and construction. 
Pure iron (soft iron - wrought iron) The carbon content of this kind of iron is only 0.02%. Because it is mixed with some slag, it is fibrous and the melting temperature is high, about 1540 degrees Celsius, so it cannot be used for welding. Pure iron is flexible. And it has high tensile strength and high corrosion resistance, and pure iron is not used in construction, but in the production of cast iron and steel. Pig iron is divided into the following categories according to its crystal structure. White pig iron: White pig iron is produced by high-speed cooling of pig iron, and it is white because its carbon does not turn into graphite when quenched, and the color remains bright (silver-white). White pig iron is used in the production of metal and steel. The content of silicon in white pig iron is low, the material is hard and brittle, and the section also has small and light grains. Gray pig iron: Gray cast iron is made from cast iron that has been cooled at a slow rate, it is gray because its carbon turns into graphite as it cools slowly and the color remains dark. Gray pig iron is used to make cast iron. The silicon content of gray cast iron is high, it is not brittle, it is softer than white cast iron, and the section also has coarse ash particles. 
Semi-gray pig iron: The material in this pig iron lies between white pig iron and gray pig iron and is used in the production of steel and hard cast iron. What is cast iron? Cast iron is made from pig iron, which is melted in special furnaces with some scrap iron to burn off some of its carbon, while impurities such as sulphur, phosphorus, etc., which greatly affect its properties, are melted and the remaining is melted. metal is removed Also contains some manganese and is called cast iron. Alloys of cast iron, iron, carbon, manganese and silicon. Manganese hardens cast iron, while silicon converts cast iron carbon to graphite. The carbon content of cast iron is 2-3.5% by weight, and the type of cast iron depends on the cooling rate and the type of pig iron used in production. The melting point of cast iron is between 1420-1470k, which is lower than its main constituents, making it the first molten product after the simultaneous heating of carbon and iron. Cast iron is very strong, hard and brittle, and even white cast iron heats up. It can cause objects to break. Cast iron's relatively low price and properties have led to its use in various industries. In the construction industry, cast iron is used for the production of water and sewer pipes, fences, floors, fittings, etc. properties of cast iron Like cast iron, cast iron changes from a solid state to a liquid state, and there is no paste state, so it does not have good hammering properties. Cast iron is hard and brittle, has a higher fire resistance than steel, and rusts slowly. For every 1 degree increase in temperature, the length increases by 0.01 mm. Types of cast iron Cast iron, like iron, comes in different types, and they all have high-pressure resistance. 
White cast iron: White cast iron is produced due to high speed cooling of pig iron, it is white because its carbon does not turn into graphite during the rapid cooling process and its color remains bright (silver white). They use white cast iron to make small objects. The silicon content in white cast iron is low, the material is hard and brittle, and cannot be filed. The broken surface also has small and bright particles. Gray cast iron: Gray cast iron is made by cooling pig iron at a slow rate and it is gray because its carbon turns into graphite during the slow cooling process and it remains dark in color. Gray cast iron is used for the production of cast iron pipes, studs, window profiles, cast iron road coverings, cast iron grates, electrical accessories, etc. Gray cast iron is softer than white cast iron, its material is hard and brittle and has the ability to hammer. The broken surface also has coarse and black particles. Semi-grey cast iron: Its material is between white cast iron and gray cast iron. Hard cast iron: To make hard cast iron, the cast iron is heated, then the outer surface cools quickly, the inside cools slowly, so the surface is white cast iron, the core is gray cast iron, this cast iron wears slowly, from it is used to make pipes under bridge decks. Soft cast iron: To increase the impact strength of cast iron and make it ductile, white and semi-gray cast iron castings are heated with some iron oxide powder to burn off some of the carbon, reducing its brittleness and softening it. Use this cast iron to make door and window fittings, key locks, faucets, and other small items. 
Difference between cast iron and steel
Before going to the difference between cast iron and steel we better get to know the qualities of both. Cast iron generally refers to gray iron, ductile iron and cast iron, including castings with a carbon content of more than 2%.
- advantage
- good swing
- Abrasion resistance
- good workability
- low crack sensitivity
- lack
- very low tensile strength
- small stretch
- use
This metal can only be used for some metal parts with moderate physical requirements. Such as protective covers, lids, frying pans, carts, frames, floors, hammers, small handles, bases, frames, boxes, knives, beds, bearings, tables, wheels, covers, pumps, faucets, pipes, cabins, engine blocks, etc. Usually use cast iron. gray cast iron In the higher grades, gray cast iron is able to withstand greater loads and has some hardness or corrosion resistance. This property of cast iron makes it possible to manufacture some important castings such as cylinders, gears, bases, flywheels, bearing housings, cylinder blocks, cylinder liners, pistons, gearboxes, brake wheels, connecting plates, intermediate pressure valves, etc. cast. iron. 
steel Cast steel usually refers to ordinary hard steel and alloy steel, which is a cast steel profile with a carbon content of less than 2%. Characteristics of steel
- Design flexibility
The main advantage of cast steel is design flexibility. In other words, casting designers have maximum freedom to choose casting designs. This results in complex shapes and hollow cross-sections. Cast steel is very flexible and variable in industrial metallurgy. In fact, different chemical components can be selected according to different needs in the project. This property provides more opportunities to choose mechanical and thermal properties on a larger scale. It also has good cooking and kneading abilities.
- Resist
Cast steel is an isotropic material that can be used for the overall resistance structure of steel castings. This increases the reliability of the project. In addition, its design and weight, short lead times, price and economy give steel a special competitive advantage.
- Larger weight range
The weight range of steel castings is wider, so the molten weight of precision castings can be as low as tens of thousands of grams, and large steel castings can reach several tons, tens of tons or hundreds of tons.
- Mechanical properties
Steel castings can be used in many different conditions. Its mechanical properties are superior to other cast alloys and various high-alloy metals for special purposes. It is important to note that pressure vessel castings are subject to high tensile stresses or dynamic loads on parts. Steel castings will be the first choice in low or high temperature conditions where large and important parts are filled with critical parts.
The difference between steel and cast iron
- Corrosion and rust resistance
In terms of corrosion, cast iron has better resistance than steel. Of course, this does not mean that it is insensitive to corrosion. If left unprotected, both metals will oxidize and eventually degrade in the presence of moisture. To avoid this, it is recommended to apply a coat of paint to both metals.
- Ability to fall
Cast iron is relatively easy to cast because it is easy to cast and does not shrink like steel. This easy casting makes cast iron an ideal metal for building or decorating iron structures such as fences and iron street tools.
- Costs
The production technology of hard steel is expensive and the production process is very complicated. This makes it more expensive to produce than cast iron. Therefore, ductile iron has many disadvantages. Malleable iron is used in many areas, including pressurized pipes and fittings, automotive applications, agriculture, road building and construction planning, and general engineering applications. In all industrial jobs such as welding, machining, material engineering, etc., the ability to distinguish between cast iron and cast iron is one of the most important topics in manufacturing. Iron: Iron is made of mild steel. The quality of this alloy is determined by low percentages of carbon and manganese. (less than 0.08% carbon and 0.06% manganese) 
Steel: Refined molten iron is converted into steel by adding a certain amount of carbon and alloying metals such as vanadium, chromium, titanium, manganese, and nickel. The maximum carbon content in steel is around 2%. Cast iron: Cast iron is an alloy of iron and carbon, typically 3 to 5 percent carbon and 1 to 3 percent silicon. Cast iron has a higher carbon content than steel. Cast iron is an important class of casting alloys. In the past, steel was described as an alloy of iron and carbon, but today, although some of the main types of steel exist, such as interstitial-free (IF) steel and Type 409 ferritic stainless steel, carbon is an impurity found in hundreds of It is no longer possible to describe steel as an alloy of iron and carbon within a few ten thousandths. Steel must per definition contain at least 50% iron and one or more other alloying elements. These elements typically include carbon, manganese, silicon, nickel, chromium, vanadium, molybdenum, titanium, niobium and aluminum, respectively. The melting point of cast iron is lower than that of iron. Cast iron is more susceptible to corrosion than iron. Cast iron is drier and less flexible than steel, and it is iron.