mat and proc welding quiz

In the four-digit aluminum index system number 2024, the first digit indicates

the major alloying element

Which of the following describe the effects of annealing steel and aluminum alloys?

Decreasing internal stresses and softening of the metal

Which heat-treating process of metal produces a hard, wear-resistant surface over a
strong, tough core?

Case hardening.

Which heat-treating operation would be performed when the surface of the metal is
changed chemically by introducing a high carbide or nitride content?

Case hardening

Normalizing is a process of heat treating

iron-base metals only.

Which of the following occurs when a mechanical force such as rolling, hammering, or
bending is repeatedly applied to most metals at room temperature?

The metals become strain or work hardened or cold worked.

The reheating of a heat treated metal, such as with a welding torch

can significantly alter a metal's properties in the reheated area.

Why is steel tempered after being hardened?

To relieve its internal stresses and reduce its brittleness

What aluminum alloy designations indicate that the metal has received no hardening or
tempering treatment?

3003-F

Which material cannot be heat treated repeatedly without harmful effects?

Clad aluminum alloy

What is descriptive of the annealing process of steel during and after it has been
annealed?

Slow cooling; low strength

What is generally used in the construction of aircraft exhaust collectors, stacks, and
manifolds?

Stainless steel

What metal has special short-time heat properties and is used in the construction of
aircraft firewalls?

Titanium alloy

Alclad is a metal consisting of

pure aluminum surface layers on an aluminum alloy core.

The core material of Alclad 2024-T4 is

heat-treated aluminum alloy, and the surface material is commercially pure aluminum

The aluminum code number 1100 identifies what type of aluminum?

99 percent commercially pure aluminum

Why should an aircraft maintenance technician be familiar with weld nomenclature?

In order to gain familiarity with the welding technique, filler material, and
temperature range used.

(Refer to Figure 44.) Identify the weld caused by an excessive amount of acetylene.

3

(Refer to Figure 44.) Select the illustration which depicts a cold weld

2

Why is it considered good practice to normalize a part after welding?

To relieve internal stresses developed within the base metal.

Holes and a few projecting globules are found in a weld. What action should be taken?

Remove all the old weld, and reweld the joint

Which condition indicates a part has cooled too quickly after being welded?

Cracking adjacent to the weld

Select a characteristic of a good gas weld.

The weld should taper off smoothly into the base metal

One characteristic of a good weld is that no oxide should be formed on the base metal
at a distance from the weld of more than

½ inch

In examining and evaluating a welded joint, a mechanic should be familiar with

likely ambient exposure conditions and intended use of the part, along with type of
weld and original part material composition

(Refer to Figure 45.) What type weld is shown at A?

Butt

(Refer to Figure 45.) What type weld is shown at B?

Double Butt

(Refer to Figure 45.) What type weld is shown at G?

Lap