Chapter 10, Problem 8RQ

Use the following phase diagram for questions 7 and 8.

The following phase diagram for the processing of a polymer relates the applied pressure to the raw material porosity.

• Region A or B = porosity is too high or too low for the material to be usable.
• Region C = combinations in this region yield material with defects, such as cracking or flaking.
• Region D = below a pressure of 15 pound-force per square inch [psi] the polymer cannot be processed.
• Region E = optimum region to operate.

There are often multiple ways to solve the same problem; here we look at a few alternative ways to determine the phase of the material and the processability of the material.

1. 8. a. In column A and column B, use data validation to restrict the user from entering values outside the valid parameter ranges—pressure: 0–35 psi and porosity: 0–100%.
   1. b. In column C, develop the equation for the line dividing the phases of Region E and Region C.
   2. c. In column D, write an expression to determine the phase of the material (phase A–phase E).
   3. d. In column E, write an expression to determine if the material is processible.
   4. e. When the conditions of phase E are met, the cell should be highlighted by conditional formatting.
   5. f. Write an expression in column F to tell the user why the material was rejected. For example, under the conditions of pressure = 25 psi and porosity= 40%, the statement might say “Porosity too low.”