Find the constants $\mathrm{k}$ and $\mathrm{m}$ relating the secondary dendrite arm spacing to the local solidification time by plotting the following data on a $\log -\log$ plot:

What is the difference between fusion welding and brazing and soldering?

An aluminum alloy plate with dimensions $20 \mathrm{~cm} \times 10 \mathrm{~cm} \times 2 \mathrm{~cm}$ needs to be cast with a secondary dendrite arm spacing of $10^{-2} \mathrm{~cm}$ (refer to Figure 9-6). What mold constant B is required (assume $n=2$ )?

Define the terms brazing and soldering.

What solidification time is required for a casting of $9.5 \mathrm{~cm}^3$ and a mold contact area of $10.0 \mathrm{~cm}^2$? The mold constant is $838 \mathrm{~s} / \mathrm{cm}^2$.

Explain why silicate glasses tend to form amorphous glasses, however, metallic melts typically crystallize easily.

A 3-in.-diameter casting was produced. The times required for the solid-liquid interface to reach different distances beneath the casting surface were measured and are shown in the following table:

Find the constants $\mathrm{B}$ and $n$ in Chvorinov's rule by plotting the following data on a $\log \log$ plot:

How can processing influence crystallinity of polymers?

A $5-\mathrm{cm}$-diameter sphere solidifies in $1050 \mathrm{~s}$. Calculate the solidification time for a $0.3 \mathrm{~cm} \times 10 \mathrm{~cm} \times 20 \mathrm{~cm}$ plate cast under the same conditions. Assume that $n=2$

Assume that instead of asphericalnucleus, we have a nucleus in the form of a cube of length $x$. Calculate the critical dimension $x^*$ of the cube necessary for nucleation. Write an equation similar to Equation 9-1 for a cubical nucleus, and derive an expression for $x^*$ similar to Equation 9-2.

Define the following terms: nucleation, embryo, heterogeneous nucleation, and homogeneous nucleation.

What is a spherulite?

A 2-in. cube solidifies in $4.6 \mathrm{~min}$. Assume $n=2$. Calculate (a) the mold constant in Chvorinov's rule; and (b) the solidification time for a $0.5$ in. $\times$ $0.5$ in. $\times 6$ in. bar cast under the same conditions.