Table 3-1.--Rivet Material Identification
MATERIAL OR
CODE LETTERS
HEAD MARKING ON
ALLOY
RIVET
1100-F
A
Plain
2117-T4
AD
Indented dimple
2017-T4
D
Raised teat
2024-T4
DD
Raised double dash
5056-H32
B
Raised cross
solution-heat-treated and cold-worked (T3) temper
made. Table 3-1 includes a listing of the most common
after driving. The 2117-T4 rivet is in general use
of these codes. The alloy code is followed by two
throughout aircraft structures, and is by far the most
numbers separated by a dash. The first number is the
widely used rivet, especially in repair work. In most
numerator of a fraction, which specifies the shank
cases the 2117-T4 rivet may be substituted for 2017-T4
diameter in thirty-seconds of an inch. The second
and 2024-T4 rivets for repair work by using a rivet with
number is the numerator of a fraction in sixteenths of an
the next larger diameter. This is desirable since both the
inch, and identifies the length of the rivet. The rivet
2017-T4 and 2024-T4 rivets must be heat treated before
code is shown in figure 3-2.
they are used or kept in cold storage. The 2117-T4
Rivet Composition
rivets are identified by a dimple in the head.
ALLOY 2017 AND 2024 RIVETS.--Both these
Most of the rivets used in aircraft construction are
rivets are supplied in the T4 temper and must be
made of aluminum alloy. A few special-purpose rivets
heat-treated. These rivets must be driven within 20
are made of mild steel, Monel, titanium, and copper.
minutes after quenching or refrigerated at or below
Those aluminum alloy rivets made of 1100, 2117, 2017,
32F to delay the aging time 24 hours. If either time is
2024, and 5056 are considered standard.
exceeded, reheat treatment is required. These rivets
ALLOY 1100 RIVETS.--Alloy 1100 rivets are
may be reheated as many times as desired, provided the
supplied as fabricated (F) temper, and are driven in this
proper solution heat-treatment temperature is not
condition. No further treatment of the rivet is required
exceeded. The 2024-T4 rivets are stronger than the
before use, and the rivet's properties do not change with
2017-T4 and are, therefore, harder to drive. The
prolonged periods of storage. They are relatively soft
2017-T4 rivet is identified by the raised teat on the
and easy to drive. The cold work resulting from driving
head, while the 2024-T4 has two raised dashes on the
increases their strength slightly. The 1100-F rivets are
head.
used only for riveting nonstructural parts. These rivets
ALLOY 5056 RIVETS.--These rivets are used
are identified by their plain head, as shown in table 3-1.
primarily for joining magnesium alloy structures
ALLOY 2117 RIVETS.--Like the 1100-F rivets,
because of their corrosion-resistant qualities. They are
these rivets need no further treatment before use and
supplied in the H32 temper (strain-hardened and then
can be stored indefinitely. They are furnished in the
stabilized). These rivets are identified by a raised cross
solution-heat-treated (T4) temper, but change to the
on the head. The 5056-H32 rivet may be stored
Figure 3-2.--Rivet coding example.
3-2
