Table 13-3.--SAE Specification for Plain Carbon Steel
Figure 13-18.--Bars.
Table 13-2.--SAE Numbers with Corresponding Alloying
Elements
SAE
Type of Steel
Number
1XXX
Carbon Steels
Plain carbon
10XX
--Infix letters are used occasionally to denote
Free cutting (screw lock)
11XX
variations or modifications in the basic alloy
13XX
High manganese
composition. There are only two infix letters used: B
(boron) and L (lead). When either of these letters are
Nickel Steels
2XXX
used, it indicates the addition of that element.
3.50% nickel
23XX
5.00% nickel
25XX
Example: 5040 basic composition
50B40 addition of boron
Nickel-Chromium Steel
3XXX
1.25% nickel, 0.60% chromium
31XX
--Suffix letters are normally used when dealing
33XX
3.50% nickel, 1.50% chromium
with stainless steel. When used in this context, they
indicate a variation in the basic chemical composition.
Molybdenum Steels (0.25% molybdenum)
4XXX
The suffix letters used are as follows:
41XX
1.0% chromium
0.5% chromium, 1.8% nickel
43XX
A, B, and C --Used to denote three types of steel
2% nickel
46XX
differing only in carbon content
3.5% nickel
48XX
F--Denotes a free machining steel
Chromium Steels
5XXX
Se--Denotes the addition of selenium
Low chrome
51XX
Example: 3033A .40% - .50% carbon
Medium chrome
52XX
AISI CLASSIFICATION SYSTEM.--As
Zhromium-Vanadium Steels
6XXX
previously mentioned, the AISI code system uses a
letter before the number to show the process used in the
Nickel-Chromium-Molybdenum
8XXX
making of the steel. The following letters are used:
(low amounts)
Silicon-Manganese
92XX
A--Acid
Figure 13-19.--SAE classification.
13-15