Concept explainers
If 500 g of a 40 wt% Ag–60 wt% Cu alloy is slowly cooled from 1000°C to just below 780°C (see Fig. P8.23):
- a. How many grams of liquid and proeutectic alpha are present at 850°C?
- b. How many grams of liquid and proeutectic alpha are present at 780°C + ΔT?
- c. How many grams of alpha are present in the eutectic structure at 780°C − ΔT?
- d. How many grams of beta are present in the eutectic structure at 780°C − ΔT?
(a)
Refer Fig P8.23, if
Determine the grams of liquid and proeutectic alpha present at
Answer to Problem 24AAP
The weight of liquid and proeutectic alpha phase is
Explanation of Solution
Express wt% of liquid.
Express wt% of proeutectic
Express the weight of liquid phase.
Express the weight of proeutectic
Hence, the weight of liquid and proeutectic alpha phase is
(b)
Refer Fig P8.23, if
Determine the grams of liquid and proeutectic alpha present at
Answer to Problem 24AAP
The weight of liquid and proeutectic alpha phase is
Explanation of Solution
Express wt% of liquid.
Express wt% of proeutectic
Express the weight of liquid phase.
Express the weight of proeutectic
Hence, the weight of liquid and proeutectic alpha phase is
(c)
Refer Fig P8.23, if
Determine the grams of alpha present in the eutectic structure at
Answer to Problem 24AAP
The weight of alpha is
Explanation of Solution
Express wt% of total
Express the weight of alpha.
Hence, the weight of alpha is
(d)
Refer Fig P8.23, if
Determine the grams of beta present in the eutectic structure at
Answer to Problem 24AAP
The weight of beta is
Explanation of Solution
Express wt% of total
Express the weight of beta.
Hence, the weight of beta is
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Chapter 8 Solutions
Foundations of Materials Science and Engineering
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