Quiz # 4 MECH 321 Winter 2020
NAME: ID #:
INSTRUCTIONS: Please put your answers below each question, use more pages as
required.
Either:
1. SAVE the file as a word.doc, or pdf, with your ID number and then UPLOAD using
the Moodle assignment.
2. Scan or take pictures of your pages and rename with your ID number and then
UPLOAD using the Moodle assignment.
QUESTION 1 (5 POINTS)
Three identical fatigue specimens (denoted A,
B, and C) are fabricated from a nonferrous
alloy. Each is subjected to one of the
maximum–minimum stress cycles listed in the
following table; the frequency is the same for
all three tests.
a) Rank the fatigue lifetimes of these 3 specimens from the longest to the shortest. Justify your
answer. (It may help to make a schematic S-N plot).
b) Suppose that the specimens are fabricated from a stainless steel. What additional information
is needed to rank the fatigue lifetimes of the specimens? Justify your answer.
c) List four measures that may be taken to increase the fatigue lifetime of a metal alloy.
ANSWER Q1
QUESTION 2 (5 POINTS)
