Biomedical Engineering Reference
In-Depth Information
Figure 3
.
3
Various causes for failure of implants that leads to revision
surgery (adopted from [46]).
p
=
E
0
(1
-
(1.21
·
p
2/3
))
(3.2)
where
E
p
is the Young's modulus of the porous sintered material,
E
0
the modulus of the bulk material and
p
the porosity.
3
.
2
.
1
Stainless Steel
In 1913, English metallurgist Harry Brearly discovered that adding
chromium to low carbon steel gives it stain resistance. In addition to
iron, carbon,
and
chromium, modern stainless steel may also contain
other elements, such as nickel, niobium, molybdenum,
and
titanium.
These elements enhance the corrosion resistance of stainless steel.
It is the addition of a minimum of 12% chromium to the steel that
makes it resist rust,
or
stain “less” than other types of steel. The
chromium in the steel combines with oxygen in the atmosphere to
