Question

Give a metallurgical explanation of what a person would be obtaining if they ordered a product by the descriptive name. A metallurgical explanation would be based on the chemical composition, the expected phases present, what type of processing would have been done to obtain the phases, and the properties you would see on a stress vs strain curve.

a) spring steel

b) machinable alloy steel

c) bake hardenable steel

d) dual phase steel

e) interstitial free steel

f) tempered martensite

Answer 1

Solution :Metallurgy is the branch of material science where we can study the physical and chemical behaviour of Metallic elements.Metallurgy is used to design metals from its ore by heat treatment processes.

1) Explanation for spring steel - Spring steel is a kind of steel which is used in Making springs of Industrial and automotive suspension springs. Spring steel is having high yield strength with low or high carbon steel.This metal is also having the property to regain their shape and position despite of heavy load and deflection applied on it.

Process of heat treatment to obtain: - The spring steel is generally obtained in Electric arc Furnace by ESR. This is obtained by Herdening at 860^oC for 1.25h.Now quenching to room temperature from 400^oC for 3 hours.

  Microstructural report enunciated the presence of temperered lath martensite with small ferrite(delta-ferrite) with austinite grain boundaries.

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b)Explanation for Machinable Alloy steel - A specific kind of steel that is contained specific amount of Silicon, copper, sulphur, and magnesium in addition of Carbon,It is known as Machinable Alloys.

Process of Heat Treatment to obtain MACHINABLE ALLOY Steel - Alloy steel is obtained by heat treatment normalized at 899^oC and then heat to 816^oF and then quenched to room temperature.

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c) Explanation- Bake Hardenable Steel as follows -

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d) Explanation- Dual Phase steel as follows-

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e) Explanation for Interstitial free steel as follows -

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f) Explanation for tempered Martensite as follows -