Table of Contents
How do you make gray cast iron?
Grey iron can be alloyed with small amounts of copper, molybdenum, vanadium or chrome to produce increasingly stronger irons as the alloy levels are increased. This is achieved by controlling the amount of ferrite and pearlite in the iron matrix.
What is meant by GREY cast iron?
Gray cast iron is a type of iron with carbon content greater than 2\% and a graphitic microstructure. It is one of the most common types of cast iron used in applications. it is relatively inexpensive, malleable and durable.
What is GREY cast iron made of?
graphite
Gray cast iron. Gray cast iron is a broad term used for a number of cast irons whose microstructure is characterized by the presence of flake graphite in the ferrous matrix. Such castings often contain 2.5\%–4\% carbon, 1\%–3\% silicon, and some additions of manganese ranging from 0.1\% to 1.2\%.
How is white cast iron produced and how is it different from GREY cast iron?
Like gray cast iron, white cast iron features many small fractures. 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.
Is gray iron magnetic?
Magnetic Properties The actual graphite structure and the type of grey iron influence properties such as permeability, coercive force and hysteresis. All grey irons exhibit ferromagnetism except austenitic grades.
Is GREY cast iron Ionic?
Solution : [c] Grey cast iron is a metallic solid.
Is gray cast iron magnetic?
The magnetic properties of gray cast iron vary widely, from low permeability and high coercive force to high permeability and low coercive force.
How is white iron produced?
White cast iron is formed when the carbon in solution is not able to form graphite on solidification. White cast irons are hard and brittle; they cannot easily be machined. The presence of different carbides, depending on the alloy content, makes white cast irons extremely hard and abrasion resistant but very brittle.
Is gray iron the same as ductile iron?
While gray iron does not have a measurable yield strength, the range for tensile strength is 20,000 psi – 60,000 psi. Impact – Ductile iron has a greater resistance to impacts, and is able to resist a minimum of 7 foot pounds of impact (versus 2 pounds of impact for gray iron).
What is the yield strength of GREY cast iron?
Comparison of Mechanical Properties of Cast Iron with Steel Castings
| Property | Gray Iron | Ductile Iron |
|---|---|---|
| Tensile strength (Ksi) [U] | 25 to 50 | 60 to 100 |
| Yield strength (Ksi) | 40 to 60 | |
| Elongation (\%) [EL] | <1 | 20 |
| Hardness (BHN) | 160 to 210 | 170 to 220 |
What is the yield strength of grey cast iron?
How are grey iron castings made?
Commonly used process for grey iron castings in the market is produced by sand casting. The processes using sand as the mold media have a somewhat similar effect on the rate of solidification of the casting, while the permanent mold process has a very marked effect on structure and properties.
What is grey iron?
Grey iron, or grey cast iron, is a material type of cast iron with graphitic microstructure. We call this kind of material grey iron because of the gray color of the fracture. For the graphite lubricating the cut and breaking up the chips, grey iron is a common cast alloy due to its relatively low cost and good machinability.
What is the difference between white cast iron and gray cast iron?
Gray cast iron is named after its gray fractured surface, which occurs because the graphitic flakes deflect a passing crack and initiate countless new cracks as the material breaks. White cast irons are hard and brittle. Gray cast irons are softer with a microstructure of graphite in transformed-austenite and cementite matrix.
Why is gray cast iron used for machinability?
The graphite in gray cast iron also provides lubrication during machining. This reduces the demand and level of lubrication required from the metalworking fluid used. In addition to the effects of the graphite structure on gray cast iron machinability, the metal also contains compositional elements which contribute to enhanced machinability.