Property |
Aluminum Extrusions |
Molded Plastic |
Wood |
Vinyl
(Polyvinyl Chloride) |
Strength (Tensile)
|
Very good mechanical properties.
|
Wide variation in properties from .08
to .8 tensile strength of aluminum extrusions for glass filled compounds. |
Good compressive properties, variable
with the species of wood and moisture content. |
Low mechanical properties. |
| Density |
Lightweight; about 1/3 that of copper
or steel. |
Very lightweight; about 60% the weight
of aluminum. |
Very lightweight. about 1/3 the density
of aluminum. |
Very lightweight about 60% the density
of aluminum. |
| Strength to Weight Ratio |
Very Good. |
Low-good. |
Low-good. |
Low-good. |
| Corrosion Resistance |
Excellent; it can be further increased,
along with enhanced appearance, through anodizing or other coatings. |
Excellent; choice of compound and color
important for weatherability (UV). |
Not directly applicable; decomposes
in the presence of some acids. |
Excellent; high resistance to aikalis
and salts but is attacked by organic solvents and strong acids. |
| Formability |
Easily formable and extruded in a wide
variety of complex shapes including multi-void hollows. Formable to
net shapes, and extrusions provide for the placement of metal where
it's needed. |
Easily formed or molded into complex
shapes. |
Poor; cannot be routinely formed. |
Easily formed or molded into complex
shapes. |
| Electrical Conductivity |
Excellent; on a pound for pound basis,
twice as efficient as copper, used in bus bar and electric connector
applications. |
Poor; used as an insulator, high dielectric
capability. |
Poor; cannot be used as an electrical
conductor Usually cannot be employed as an insulator. |
Poor; electrical and thermal insulating
characteristics. |
| Thermal Conductivity |
Excellent; ideal for heat exchanger
applications. |
Poor; low coefficient of thermal (heat)
transfer. |
Poor. |
Poor. |
Finishing
|
A near limitless array of finishes
can be applied including mechanical and chemical prefinishes, anodic
coatings, paints and electroplated finishes. |
Color can be integral with material
as well as plated, painted, and hot stamped. |
Paint and stain coatings can be employed. |
Color can be integral with material. |
| Recyclability |
High scrap value; routinely reprocessed
to generate new extrusions. |
Routinely reprocessed but loses properties;
reprocessed material is added to new stock. |
Low scrap value. |
Low scrap value routinely reprocessed. |
| Tooling Economics |
Extrusion tooling is relatively inexpensive.
Generally, a simple shape will cost only a few hundred dollars. Short
lead times for tooling construction. |
Tooling is expensive; generally in
the thousands of dollars. Long lead times required. |
Very inexpensive. |
Relatively inexpensive. |
| Energy Savings |
Lightweight aluminum extrusions can
offer energy savings for transportation vehicles. |
Savings for vehicles, processing, insulation. |
In certain applications. |
Can offer energy savings in appropriate
transportation applications. |
| Combustibility |
Noncombustible; does not emit any toxic
fumes when exposed to high temperatures. |
Combustible; may emit toxic fumes when
exposed to high temperatures. |
Combustible; emits toxic fumes while
burning. |
Combustible. May emit toxic fumes when
exposed to high temperatures. |
Material
Comparison 