What are the chemical properties of cast iron?
What are the chemical properties of cast iron?
Cast iron is one of the oldest ferrous metals in commercial use. It is primarily composed of iron (Fe), carbon (C) and silicon (Si), but may also contain traces of sulfur (S), manganese (Mn) and phosphorus (P). It has a relatively high carbon content of 2% to 5%.
What controls mechanical properties of grey cast iron?
For any given gray iron composition, the rate of cooling from the freezing temperature to below about 650 °C (1200 °F) determines the ratio of combined to graphitic carbon, which controls the hardness and strength of the iron.
What is the composition of grey cast iron?
This material is a ternary Fe-C-Si alloy. Grey cast iron is characterized by its graphitic microstructure. Most cast irons have a chemical composition of 2.5 to 4.0% carbon, 1 to 3% silicon, and the remainder is iron.
What is the difference between white cast iron and grey cast iron?
The difference is that white cast iron features cementite below its surface, whereas gray cast iron features graphite below its surface. The graphite creates the appearance of a gray color, while the cementite creates the appearance of a white color.
Why grey cast iron is brittle and weak in tension?
Gray cast irons are comparatively weak and brittle in tension due to its microstructure; the graphite flakes have tips which serve as points of stress concentration. Strength and ductility are much higher under compression loads.
What is grey iron used for?
Grey cast iron applications It is used in applications where its high stiffness, machinability, vibration dampening, high heat capacity and high thermal conductivity are of advantage, such as internal combustion engine cylinder blocks, flywheels, gearbox cases, manifolds, disk brake rotors and cookware.
Is grey cast iron brittle?
Unfortunately the only commonly known property of gray iron—brittleness—is also assigned to “cast iron” and hence to all cast irons. Gray iron is so named because its fracture has a gray appearance. It contains carbon in the form of flake graphite in a matrix that consists of ferrite, pearlite, or a mixture of the two.
Which type of casting iron is the strongest?
gray cast iron
While the hardness and strength of steel almost always increase as carbon content rises, in the case of gray cast iron the strongest, hardest grades have less carbon than some of the lower-strength, less expensive grades. Gray iron is usually cast in sand molds, and allowed to cool normally in the mold.
What is the reason of toughness of grey cast iron?
What is the reason of low toughness of grey cast iron? Explanation: Grey cast iron has very poor toughness. Its major reason is notch like an effect of graphite flakes. These flakes increase stress concentration in it lowering toughness.
How does grey cast iron increase tensile strength?
C. Addition of Copper increases both tensile strength and hardness of gray iron.
What is the hardness of gray cast iron?
approximately 235 MPa.
Hardness of Gray Cast Iron – ASTM A48 Class 40 Brinell hardness of gray cast iron (ASTM A48 Class 40) is approximately 235 MPa. In materials science, hardness is the ability to withstand surface indentation (localized plastic deformation) and scratching.
What is the chemical composition of grey cast iron?
What is GREY iron used for?
Which type of cast iron is strongest?
What is the tensile strength of grey cast iron?
| Physical Properties | Metric | English |
|---|---|---|
| Tensile Strength, Ultimate | 115 – 700 MPa | 16700 – 102000 psi |
| Tensile Strength, Yield | 65.5 – 420 MPa | 9500 – 60900 psi |
| Elongation at Break | 1.00 – 15.0 % | 1.00 – 15.0 % |
| Modulus of Elasticity | 62.1 – 162 GPa | 9000 – 23500 ksi |
What is the difference between cast iron and Grey Iron?
Why gray iron is brittle and weak in tension?
How do you increase hardness in cast iron?
Common Heat Treatment for the Specific Cast-Iron Types Tempering is performed between 205°C (400°F) and 260°C (450°F) for at least 4 hours. This tempers the martensite, relieves some of the transformation stresses, and increases the strength and impact toughness by 50-80%.
Is cast iron the same as gray iron?
Gray iron, or grey cast iron, is a type of cast iron that has a graphitic microstructure. It is named after the gray color of the fracture it forms, which is due to the presence of graphite. It is the most common cast iron and the most widely used cast material based on weight. It is used for housings where the stiffness of the component is more important than its tensile strength, such as
What are the mechanical properties of cast iron?
Properties of Cast Iron. Material properties are intensive properties,that means they are independent of the amount of mass and may vary from place to place within the system at
What is gray iron casting?
Properties of Gray Cast Iron – ASTM A48 Class 40. The carbon and silicon contents of gray cast irons vary between 2.5 and 4.0 wt% and 1.0 and 3.0 wt%,…
What are uses of cast iron?
Cast iron is especially used to make stoves which can be heated with coal or wood. It is also used to make frying pans. Further, the spoons, forks and plates are made of stainless steel. The steel is also used to make the frame of stoves to give strength and an attractive bright appearance to the stoves.