Aerospace Materials Questions and Answers Part-10

1. If the specimen being tested is heavy in weight, it should have a __________ cross-section.
a) circular
b) spherical
c) rectangular
d) triangular

Answer: c
Explanation: For a specimen being tested that is heavy in weight, the rectangular cross section should be present. The cross section can be obtained by applying a smooth file at the corner of the test specimen.

2. The usual angle through which bending should be obtained in a bending test is ________
a) 180°
b) 120°
c) 75°
d) 90°

Answer: a
Explanation: The usual angle with which the test specimen should be bent in the bending test is 180°. This is over a pin that has the same diameter as that of the test specimen being used in the experiment. Cracking should be avoided.

3. It is usually very easy to obtain the exact bending radius desired in a bending test.
a) True
b) False

Answer: b
Explanation: It is not very effortless or easy to obtain the exact desired radius of bending in the bending test being performed. But this test can often be used in shops etc. to check the properties of the material if there is a doubt about them.

4. The minimum length of wire that can be used in a reverse bend test is ________
a) 5 inches
b) 23 inches
c) 10 inches
d) 4.5 inches

Answer: c
Explanation: In the reverse band test, the minimum length of wire used in the experiment is 10 inches. The specifications to perform the experiment on the specimen truly depend on the nature of the material.

5. _________ usually undergoes a reverse bend test.
a) Round steel wire
b) Glue
c) Plated iron
d) Wood

Answer: a
Explanation:Round steel wire is usually the most widely used specimen while performing the reverse bend test in laboratories. Wood and glue cannot be used or have the bending test performed on them.

6. The radius to which the jaws of the vice rounded to for wires of diameter less than 3/16 inches is _________
a) 2/15
b) 12/7
c) 3
d) 3/16

Answer: d
Explanation: If the diameter of the wire in which the test is being carried out is less than 3/16 inches of diameter, the jaws of the vice are rounded to 3/16 inches. For wires of greater weight, the vice is set to 3 times the diameter of the wire.

7. The maximum rate up to which bending is done per minute is ________ in reverse bend test
a) 35
b) 50
c) 5
d) 26

Answer: b
Explanation: The maximum speed up to which the bending experiment can be conducted in the reverse band test is 50 bends per minute. This should be done while considering how it could be prone to heating.

8. What is the rate of bending carried out for heavy wires?
a) 65 bending’s
b) 7 bending’s
c) 80 bending’s
d) 50 bending’s

Answer: b
Explanation: For heavy wire, the rate of bending in the reverse bend test is 7 bends per minute. For small wire, the rate of bending in the experiment is fifty bends per minute. This is the specification given.

9. A bend of what angle is considered as a single bend?
a) 45°
b) 90°
c) 180°
d) 270°

Answer: b
Explanation: In the reverse bend test, a single bend is usually considered to be 90° in each test. The machine goes both back and forth each time 90°, making a total of 180°, but one bend is considered to be 90°.

10. Aircraft materials need a bending test.
a) True
b) False

Answer: a
Explanation: It is true that most aircraft materials need to undergo and pass a bending test. This gives the impression and meets the requirement of needing a material that is more ductile and not brittle in nature.