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At t = 0, a cube of pure Marylandium (Md) 5 cm on each side is put into a furnace at 1000 °C with a carbon (C) atmosphere at a concentration of 0.1wt%. The diffusion coefficient for C in Md at this temperature is 2 × 109 m2 /s. The density of C is 2.25 g/cm3 and Md is 8 g/cm3 . (a) Sketch the system in one dimension (1D), indicating the materials, locations, variables, and direction of atomic motion. (b) Make a sketch of the C concentration profile in the material at t = 0 clearly labeling the x and y axes with values, units and what is represented. (c) Add a qualitative sketch of the C concentration profile after a short time t1. (d) Add a qualitative sketch of the C concentration profile at a longer time t2.

User Jespern
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Answer:

See explaination

Step-by-step explanation:

Diffussion coefficient can be described as the diffusion by which the mass of a substance dM diffusing in time dt through the surface dF normal to the diffusion direction is proportional to the concentration gradient grad c of this substance: dM = −D grad c dF dt.

Lets go ahead and make the sketch of concentration profile.

Please refer to attachment for details.

At t = 0, a cube of pure Marylandium (Md) 5 cm on each side is put into a furnace-example-1
At t = 0, a cube of pure Marylandium (Md) 5 cm on each side is put into a furnace-example-2
At t = 0, a cube of pure Marylandium (Md) 5 cm on each side is put into a furnace-example-3
User Vorujack
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