Question

6. A 2.0-kg specimen of an 85 wt% Pb-15 wt% Sn alloy is heated to 200°C (390°F); at this temperature it is entirely an α-phase solid solution, The alloy is to be melted to the extent that 50% of the specimen is liquid, the remainder being the phase. This may be accomplished by heating the alloy or changing its composition while holding the temperature constant. (a) To what temperature must the specimen be heated? (b) How much tin must be added to the 2.0-kg specimen at 200°C to achieve this state?

Answer 1

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ing mass of oo, iginal altoy is , msn guen , m'alg Subs titutng in the aboue eamula ingn 。 (0-15) (a) Scanned with

3 mass new lloy will be x 100 cohere, ภา5a-alloy (neo) Substiんting , o.3k h+31 msn - 30 +100 ms 100 n,n-3+ msn-%-30 6 3 msno698H k 0.698 Hkg of机Shootdke added