Introduction
This page only relates to materials used for general
mechanical engineering.
Other pages identifying Corrosion /Chemical
Resistance are as follows
In normal mechanical and structural engineering
design materials are selected primarily for their
mechanical properties-corrosion is not an important
criteria. The systems are generally
protected against corrosion by surface
coatings.
Most machines are located indoors and are accessible
for inspection and maintenance. The
exceptions to this are machines used for construction
and agriculture. These machines may well
be used in corrosive environments but they are
generally regularly maintained and some level of
corrosion is acceptable.
In process engineering corrosion is a very important
design factor and materials are selected primarily on
their resistance to chemical attack
(corrosion). Surface coatings are often
not considered because of the risk of contaminating
the process stream.
Metal Corrosion Properties - Non Chemical
Environments
Ratings 0 = Unsuitable, 1 = poor, 2 = Fair, 3 =Fair
to Good, 4 good, 5 = good to excellent, 6=
excellent.
|
|
Fresh Water
|
Sea
Water
|
Steam
|
Steam
Cond'te
|
Air
|
|
Metal
|
Static/Turb
|
Static/Turb
|
Dry
|
Wet
|
City/Indust
|
Grey Cast Iron-
Plain or Low Alloy
|
4/3
|
4/3
|
4
|
4
|
3
|
Ductile Iron
(High Strength )
|
4/4
|
4/2
|
4
|
4
|
3
|
Cast Iron Ni_Resist.
(14% Ni, 7% Cu, 2% Cr bal Fe)
|
5/5
|
5/5
|
5
|
5
|
4
|
Ductile Iron Ni_Resist.
(24 % Ni, bal Fe)
|
5/5
|
5/5
|
5
|
5
|
4
|
|
Mild Steel- Low Alloy steels
|
4/3
|
4/2
|
4
|
4
|
3
|
Stainless Steel Ferritic
(17% Cro)
|
4/6
|
1/4
|
6
|
5
|
3
|
Stainless Steel Austenitic
(18% Cro ,8% Ni )
|
6/6
|
2/5
|
6
|
5
|
4
|
Stainless Steel Austenitic
(18% Cro 12% Ni, 2.5% Mo )
|
6/6
|
3/5
|
6
|
6
|
6
|
Stainless Steel Austenitic
(20% Cro 29% Ni, 2.5% Mo,3.5% Cu )
|
6/6
|
4/6
|
6
|
6
|
6
|
Hastelloy Alloy
(55% Ni, 17% Mo,16% Cr, 6% Fe, 4% W)
|
6/6
|
6/6
|
6
|
6
|
6
|
Inconel
(78% ni,15% Cr, 7% Fe)
|
6/6
|
4/6
|
6
|
6
|
6
|
Copper Nickel alloys
(Up to 30% Ni)
|
6/6
|
6/6
|
5
|
6
|
5
|
Monel 400
(66% Ni, 30% Cu, 4% Si)
|
6/6
|
6/6
|
6
|
6
|
5
|
Nickel Commercial
(99% Ni)
|
3/5
|
6/6
|
6
|
6
|
4
|
|
Copper and Silicon Bronze
|
6/5
|
4/1
|
5
|
6
|
5
|
|
Aluminium Brass
|
6/6
|
4/5
|
5
|
6
|
5
|
Bronze
(88% Cu,5% Sn,5% Ni,2% Zn)
|
6/6
|
5/5
|
5
|
6
|
5
|
|
Aluminium Alloys
|
4/5
|
0-5/4
|
2
|
5
|
5
|
|
Lead (Chemical or antimonial)
|
6/5
|
5/3
|
0
|
2
|
5
|
|
Silver
|
6/6
|
5/5
|
5
|
6
|
6
|
|
Titanium
|
6/6
|
6/6
|
5
|
6
|
6
|
|
Zirconium
|
6/6
|
6/6
|
5
|
6
|
6
|
|