Arulmigu Meenakshi Amman College of Engineering
Vadamavandal-604410.
Important questions and answers
CME395- CASTING AND WELDING PROCESSES
Prepared by
V.Umapathy,
Prof. /Mech.
S.No. Questions and answers
Unit-I
FERROUS CAST ALLOYS
2 – marks question and answers
1. What are ferrous alloys?
Ferrous alloys (ferro alloys) or metals are metals that consist mostly of iron (Fe). Steel is an iron-based
alloy containing typically less than 1% carbon, where iron frequently contains 2% or more carbon. Iron
and steel are widely available, strong, cheap, and can be shaped by casting.
2. What are cast iron alloys?
Cast irons, alloys of iron, carbon, and silicon, contain carbon as graphite (pure carbon), as carbide (Fe3C),
or in solid solution in austenite (austempered ductile iron (ADI), matrix austenite with 1.7–2.1% carbon)
3. What is ferrous casting?
Our unique pressure casting process consists of forcing molten metal against the mold wall under relatively
high pressure and rapidly cooling the mold. This production method enables us to produce bi-metallic
sleeves that feature high-wear resistant shells with inner cores that are tough and forgiving.
4. What is solidification of pure metals and alloys?
Solidification of pure metals is the process by which a molten pure metal cools and transforms into a solid
state at a specific melting point, while solidification of alloys is the process of cooling and transforming a
molten mixture of two or more elements (metals or non-metals) into a solid material with a complex.
5. What is the solidification of the eutectic?
The eutectic has a fixed composition in terms of species A and B, and is in fact a two-phase solid (α + β).
, Solidification of a liquid of eutectic composition proceeds by transformation of the liquid into a two-phase
solid.
6. What is the nucleation process?
Nucleation is the process by which atoms or molecules come together to form a new phase or structure.
This process is crucial in the formation of crystals, as well as in the formation of bubbles in a liquid or gas.
7. What are the effects of normal elements and alloying elements in steels?
Alloying Elements and How They Effect the Steel. Carbon, the main alloying element of steel; Increases
mechanical properties such as strength, hardness, and mechanical resistance. But besides this increase,
malleability, ductility, and toughness decrease. In addition, the tensile strength can increase up to a point.
8. What is the stainless steel?
Stainless steel is a corrosion-resistant alloy of iron, chromium and, in some cases, nickel and other metals.
Completely and infinitely recyclable, stainless steel is the “green material” par excellence. In fact, within
the construction sector, its actual recovery rate is close to 100%.
9. What is the process of desulphurization in steel making?
The principle of desulphurization is to transfer the sulfur dissolved in the liquid steel to a CaO-rich slag
phase. This process is typically carried out in a ladle furnace (LF). For this process to be successful, two
conditions need to be fulfilled: The slag must be fully liquid (liquid fraction > 0.9).
10. What is carbon steel standard specification?
Properties of medium-carbon steel
Property Value
Density 0.280 – 0.285 lb/in³
Tensile Strength, Yield 35500 – 252000 psi
Fracture Toughness 73.7 – 130 ksi-in½
Shear Modulus 10400 – 11900 ksi
, 13 and 15 marks question and answers
11 Explain Solidification of pure metals and alloys and eutectics.
Solidification, in the sense used in this context, is the process by which a liquid is transformed into a
crystalline solid. In crystal growth the solid that forms first is solvent rich as distinct from crystallisation,
in which the crystals that are formed are solute rich.
As the temperature drops further, the molten metal loses energy, and crystals begin to form. This process
starts near the mold walls, where it cools first. These crystals eventually become grains within the final
structure.
The eutectic has a fixed composition in terms of species A and B, and is in fact a two-phase solid (α + β).
Solidification of a liquid of eutectic composition proceeds by transformation of the liquid into a two-phase
solid.
For pure metals, solidification occurs at a single, constant temperature while for alloys it takes place over a
temperature range as shown by their unique cooling curves and phase diagrams. The grain structure that
forms depends on factors like cooling rate and alloy composition.
The solidification of pure metals and alloys differs in the following ways:
Pure metals: Solidify at a single, constant temperature.
Alloys: Solidify over a range of temperatures. This range is called the "mushy zone" because the material
is a mixture of liquid and solid.
Eutectic alloys: Solidify at a single temperature to form a mixture of two phases.
, Here are some other details about the solidification of metals and alloys:
Sli Solidification process
The solidification process begins when a molten metal loses energy and crystals form. This process starts
near the mold walls, where it cools first.
1. Grain structure
The grain structure that forms depends on factors like cooling rate and alloy composition.
2. Solute redistribution
Alloy solidification is characterized by solute redistribution, which can result in coring and variation in
mechanical properties.
3. Eutectic alloys
Eutectic alloys are a type of high-entropy alloy that exhibit good castability and high mechanical
strength.
The alloy of eutectic composition solidifies at a single temperature to precipitate a mixture of two phases
'α'and'β' of different compositions, 'x' and 'y' [2]. Thus, two separate phases, of two different compositions
are precipitated out at a single temperature as a consequence of freezing of an eutectic alloy.
Two types of solidification:
Vadamavandal-604410.
Important questions and answers
CME395- CASTING AND WELDING PROCESSES
Prepared by
V.Umapathy,
Prof. /Mech.
S.No. Questions and answers
Unit-I
FERROUS CAST ALLOYS
2 – marks question and answers
1. What are ferrous alloys?
Ferrous alloys (ferro alloys) or metals are metals that consist mostly of iron (Fe). Steel is an iron-based
alloy containing typically less than 1% carbon, where iron frequently contains 2% or more carbon. Iron
and steel are widely available, strong, cheap, and can be shaped by casting.
2. What are cast iron alloys?
Cast irons, alloys of iron, carbon, and silicon, contain carbon as graphite (pure carbon), as carbide (Fe3C),
or in solid solution in austenite (austempered ductile iron (ADI), matrix austenite with 1.7–2.1% carbon)
3. What is ferrous casting?
Our unique pressure casting process consists of forcing molten metal against the mold wall under relatively
high pressure and rapidly cooling the mold. This production method enables us to produce bi-metallic
sleeves that feature high-wear resistant shells with inner cores that are tough and forgiving.
4. What is solidification of pure metals and alloys?
Solidification of pure metals is the process by which a molten pure metal cools and transforms into a solid
state at a specific melting point, while solidification of alloys is the process of cooling and transforming a
molten mixture of two or more elements (metals or non-metals) into a solid material with a complex.
5. What is the solidification of the eutectic?
The eutectic has a fixed composition in terms of species A and B, and is in fact a two-phase solid (α + β).
, Solidification of a liquid of eutectic composition proceeds by transformation of the liquid into a two-phase
solid.
6. What is the nucleation process?
Nucleation is the process by which atoms or molecules come together to form a new phase or structure.
This process is crucial in the formation of crystals, as well as in the formation of bubbles in a liquid or gas.
7. What are the effects of normal elements and alloying elements in steels?
Alloying Elements and How They Effect the Steel. Carbon, the main alloying element of steel; Increases
mechanical properties such as strength, hardness, and mechanical resistance. But besides this increase,
malleability, ductility, and toughness decrease. In addition, the tensile strength can increase up to a point.
8. What is the stainless steel?
Stainless steel is a corrosion-resistant alloy of iron, chromium and, in some cases, nickel and other metals.
Completely and infinitely recyclable, stainless steel is the “green material” par excellence. In fact, within
the construction sector, its actual recovery rate is close to 100%.
9. What is the process of desulphurization in steel making?
The principle of desulphurization is to transfer the sulfur dissolved in the liquid steel to a CaO-rich slag
phase. This process is typically carried out in a ladle furnace (LF). For this process to be successful, two
conditions need to be fulfilled: The slag must be fully liquid (liquid fraction > 0.9).
10. What is carbon steel standard specification?
Properties of medium-carbon steel
Property Value
Density 0.280 – 0.285 lb/in³
Tensile Strength, Yield 35500 – 252000 psi
Fracture Toughness 73.7 – 130 ksi-in½
Shear Modulus 10400 – 11900 ksi
, 13 and 15 marks question and answers
11 Explain Solidification of pure metals and alloys and eutectics.
Solidification, in the sense used in this context, is the process by which a liquid is transformed into a
crystalline solid. In crystal growth the solid that forms first is solvent rich as distinct from crystallisation,
in which the crystals that are formed are solute rich.
As the temperature drops further, the molten metal loses energy, and crystals begin to form. This process
starts near the mold walls, where it cools first. These crystals eventually become grains within the final
structure.
The eutectic has a fixed composition in terms of species A and B, and is in fact a two-phase solid (α + β).
Solidification of a liquid of eutectic composition proceeds by transformation of the liquid into a two-phase
solid.
For pure metals, solidification occurs at a single, constant temperature while for alloys it takes place over a
temperature range as shown by their unique cooling curves and phase diagrams. The grain structure that
forms depends on factors like cooling rate and alloy composition.
The solidification of pure metals and alloys differs in the following ways:
Pure metals: Solidify at a single, constant temperature.
Alloys: Solidify over a range of temperatures. This range is called the "mushy zone" because the material
is a mixture of liquid and solid.
Eutectic alloys: Solidify at a single temperature to form a mixture of two phases.
, Here are some other details about the solidification of metals and alloys:
Sli Solidification process
The solidification process begins when a molten metal loses energy and crystals form. This process starts
near the mold walls, where it cools first.
1. Grain structure
The grain structure that forms depends on factors like cooling rate and alloy composition.
2. Solute redistribution
Alloy solidification is characterized by solute redistribution, which can result in coring and variation in
mechanical properties.
3. Eutectic alloys
Eutectic alloys are a type of high-entropy alloy that exhibit good castability and high mechanical
strength.
The alloy of eutectic composition solidifies at a single temperature to precipitate a mixture of two phases
'α'and'β' of different compositions, 'x' and 'y' [2]. Thus, two separate phases, of two different compositions
are precipitated out at a single temperature as a consequence of freezing of an eutectic alloy.
Two types of solidification:
