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

What are the sources of heat for the processes described in this chapter?

A countershaft carrying two V-belt pulleys is shown in the figure. Pulley A receives power from a motor through a belt with the belt tension. The power is transmitted through the shaft and delivered to the belt on pulley B. Assume the belt tension on the loose side at B is 15 percent of the tension on the tight side.

a.) Determine the tensions in the belt on pulley B, assuming the shaft is running at a constant speed.

b.) Find the magnitudes of the bearing reaction forces, assuming the bearings act as simple supports.

c.) Draw shear-force and bending-moment diagrams for the shaft. If needed, make one set for the horizontal plane and another set for the vertical plane.

d.) At the point of maximum bending moment, determine the bending stress and the torsional shear stress.

e.) At the point of maximum bending moment, determine the principal stresses and the maximum shear stress.

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 $n=2$ )?

What is the difference between brazing and braze welding?

Define the terms brazing and soldering.

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?

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.

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 $n=2$

What is a spherulite?

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