What are Some Important Things to Know About Grey Cast Iron?
Grey cast iron, also spelled as gray cast iron is a special kind of iron. This casting is mostly known for its grey colour which is the output of its graphite content. In other words, the graphite flakes structure makes the iron grey as confirmed by a leading grey iron casting manufacturer. This is created during the process of cooling from its carbon component. This special type of iron is the result of the materials used as well as the process of casting. The properties of this iron change based on the materials melted to pour into the mold and the casting process.
Composition
Under a powerful microscope, you can see its graphitic microstructure responsible for making the iron grey. The iron is easily distinguishable owing to its colour. You can find black graphite flakes in the casting of this iron. These flakes are responsible to cause fractures. They also cause the material to look grey. Mechanical properties of the iron depend on the shape and size of the flakes.
Uses
Grey iron castings are the most widely produced casting in comparison to any of its counterparts. The manhole covers and disc brakes of the car, for example, are made from grey iron. Other popular uses of this type of iron casting may include,
• Hydraulic components
• Car gears
• Components of automotive suspension
• Pumps
• Stove parts
• Linkages
• Plow shares
• Components of tractor
• Steering knuckle
• Different types of valves
• Components of truck suspension
• Many parts of the truck
• Housings of wind turbine
• Machinery bases
• Weights
Reasons for wide usage and popularity
The key reason for the widespread use of grey cast iron is that it is one of the least costly types of iron castings. It has good ductility, yield strength, tensile strength and impact resistance properties for almost every application. It can dampen vibrations and thus it is perfect for machinery bases. For the same reason, a topnotch grey iron casting manufacturer uses this for manufacturing various housing applications as well. Grey cast iron features high thermal conductivity. It can move heat fast and easily across the metal.
The iron is able to withstand thermal cycling. Thermal cycling is the process where the components go back and forth between cooler and warmer temperatures. This can create extensive stress and cause premature failure in some kinds of metal castings. But with grey cast iron, the chance is minimal. It can endure the stress and strain of thermal cycling.
Though this iron has less shock resistance and tensile strength, it has more compressive strength. And thus it is comparable to carbon steel. The mechanical properties of grey iron castings are mainly dependent on the shape and size of the graphite flakes present in its microstructure.
It is often accepted as the most popular engineering alloy. It is a low cost and features good machinability. The graphite content of the alloy lubricates the cuts. It also features good wear resistance properties.
