What is the critical value of G to avoid constitutional supercooling for the directional solidification of an Al-Cu alloy, containing 3 wt.% copper, at a rate of 0.05 mm/s? For these alloys, k = 0.14, m = -2.6oC/wt% and D = 3x10-5 cm 2 /s. Here G is the thermal gradient into the liquid phase, k is the partition coefficient of the alloy, and D is the diffusivity of solute in the liquid phase.

What is the critical value of G to avoid constitutional supercooling for the directional solidification of an Al-Cu alloy, containing 3 wt.% copper, at a rate of 0.05 mm/s? For these alloys, k = 0.14, m = -2.6oC/wt% and D = 3x10-5 cm 2 /s. Here G is the thermal gradient into the liquid phase, k is the partition coefficient of the alloy, and D is the diffusivity of solute in the liquid phase.

Welding: Principles and Applications (MindTap Course List)

8th Edition

ISBN:9781305494695

Author:Larry Jeffus

Publisher:Larry Jeffus

Chapter26: Welding Metallurgy

Section: Chapter Questions

Problem 29R: Why is brine quenching faster than water quenching?

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