6
STAINLESS STEEL ELECTRODES
In choosing the appropriate wire for
welding a stainless steel, there are generally fewer factors to consider
as: 1) Shielding
gases are usually limited to Ar-1% 02
for spray arc and A-1025 for short arc. All wires can be
used with either gas. 2) Wires
are for the most part chosen to match the chemistry of the base material.
3) Deoxidizer levels
are not of great importance. Table 5-3* lists the chemical requirements and
designations for all stain less steel
wires covered by theAmericanWelding Society SpecificationA5.9.
Unlike carbon and steel wires, there
are no mechanical property require ments for the resulting weld
metal. Some of the most commonly used
wire classifications and their intended uses are as follows:
ER308L (Arcaloy 308/308L)
– Wires of these types can be used for welding 304
stainless steel. The chromium
and nickel contents are identical. The lower carbon content reduces any possibility
of carbide precipitation
and the intergranular corrosion that can occur. Carbon content is less than 0.04%.
ER308LSi (Arcaloy 308Si/308LSi)
– Similar chemistry and type of materials weldable
as ER308L. However,
a higher silicon level improves the wetting characteristics of the weld metal,
particularly when Ar- 1%
02 shielding gas is used. If the dilution
of the base plate is extensive, high silicon content can cause
greater crack sensitivity than a low
silicon content. This results from the weld being fully austenitic or a low
ferrite. ER309L
(Arcaloy 309/309L) – Used to weld
type 309 and 309 stainless steel. These can been used to weld
type 304 stainless steel where severe
corrosion conditions will be encountered and for joining mild steel to
type 304 stainless.
ER316L (Arcaloy 316/316L) –
Used to weld type 316 stainless steel. The addition of molybdenum makes
this wire electrode applicable for
high service where creep resistance is desired. Carbon content is less than
0.04%. *Table
5-3 appears in the back of the book. Continued
on next page...
