Materials and processes

Question 1

Name some tools that are commonly used to assist in making visual inspection of welds.

Answer 1

Magnifying glass, flashlight, mirror, and possibly a borescope.

Question 2

What are some of the non-destructive testing methods that may be used on aluminum parts?

Answer 2

Visual, dye penetrant, eddy current, ultrasonic testing and radiography.

Question 3

What process occurs during the preparation stage of dye penetrant inspection when the penetrating liquid is applied, and then removed from a cracked part?

Answer 3

The penetrant enters the crack by capillary action and remains there until made visible by developer.

Question 4

Describe the basic steps for conducting a magnetic particle inspection.

Answer 4

Magnetize the part, coat the surface with ferromagnetic particles. If a defect is present the particles align with the defect forming a visible pattern.

Question 5

The penetration of a fillet weld should be what percentage of thickness of the base metal?

Answer 5

25 to 50 percent

Question 6

What telltale characteristic are evidence of a cold weld?

Answer 6

Cold weld has rough irregular edges that are not feathered into the base metal and has variations in penetration amount.

Question 7

A correctly made butt weld will have what bead width and how much penetration?

Answer 7

3 to 5 times the thickness of the base metal and there must be 100% penetration.

Question 8

Describe the steps involved in a dye penetrant inspection.

Answer 8

Surface is cleaned , and the penetrant is applied and has to sit for a specified time. Penetrant is then removed with a cleaner. Once removed, the part is dried and then developer is applied, results are the inspected.

Question 9

What inspection method is used for checking a nonferrous metal part for intergranular corrosion?

Answer 9

Eddy current inspection

Question 10

Why is it important that all parts be thoroughly cleaned before they are inspected by the dye penetrant method?

Answer 10

Any grease or dirt in a fault will keep the penetrant from seeping into the fault

Question 11

Why is it important to magnetize a part both circularly and longitudinally when inspecting a steel part by the magnetic practical method?

Answer 11

To detect faults that extend across as well as lengthwise within the part.

Question 12

Why is a piece of steel tempered after it has been hardened?

Answer 12

When steel is hardened it becomes brittle tempering removes some of this brittleness.

Question 13

Describe the methods of solution heat treatment of an aluminum alloy.

Answer 13

It is placed in a Furnace to a predetermined temperature, and immediately quenched in water. It is soft when it is removed but as it ages it regains it’s hardness

Question 14

What are two methods of case hardening?

Answer 14

Carburizing and nitriding

Question 15

What is indicated by the markings on the head of a solid chalk rivets ?

Answer 15

The material they are made of, and their strength

Question 16

What is the grip length of a bolt?

Answer 16

The length of the unthreaded portion

Question 17

How can you keep heat treated aluminum alloy rivets soft enough to install after the quenching process?

Answer 17

Keep the rivets in the freezer they will stay soft for a couple of days

Question 18

In what way are AN standard steel bolts identified?

Answer 18

By the code markings on the bolt head

Question 19

What is the most commonly used type of aircraft primary control cable?

Answer 19

Extra flexible 7 x 19 cable

Question 20

For what type of applications are self-locking nuts not allowed?

Answer 20

Can not be used when either the bold or nut is subject to rotation

Question 21

How do you work harden a piece of metal?

Answer 21

By cold working the metal

Question 22

Describe the primary difference between a thermosetting and a thermoplastic resin.

Answer 22

Thermosetting resin doesn’t soften when heated and chars or burns rather then melt.
Thermoplastic resins become soft and pliable when heated and harden when cooled

Question 23

Explain how thermoplastic and thermosetting resins are commonly used in modern aircraft

Answer 23

Thermosetting resins are used as a matrix material in composite structures. Plexiglas is a thermoplastic resin commonly used as windshields and windows

Question 24

Name one of the types of resins commonly used as a matrix material for aircraft composite laminates.

Answer 24

Epoxy resin

Question 25

What are some of the materials that are commonly used as a reinforcing component in a composite structure?

Answer 25

Fiberglass, Kevlar, Carbon fiber, linen and paper

Question 26

What are the reason that alloy steel is responsive to heat treatment is usually less suitable for welding ?

Answer 26

It may become brittle and lose its ductility in the area of the weld

Question 27

Give one advantage of pre- preg materials other than saving time in the construction or repair of composite components.

Answer 27

Pre-preg fabrics contain the correct amount of matrix

Question 28

What type of precision measuring instrument can be used to measure the outside dimensions of aircraft parts?

Answer 28

Outside micrometers and vernier calipers

Question 29

What should be used to make a visual inspection of a weld?

Answer 29

A magnifying glass of at least power of 10

Question 30

What system is used to identify AN type bolts

Answer 30

They have markings on the top of the bolt head and bolt diameter is measured in 16ths of an inch and length is 8th of an inch

Question 31

What is a suitable non destructive method for detecting cracks in aluminum castings and forgings

Answer 31

Dye penetrant inspection

Question 32

How can the correct grip length be determined

Answer 32

It should be equal to the thickness of the materials to be joined