METAPOR® is a composite material made of aluminum granules and epoxy resin. The material is air-permeable over the entire surface due to its micro-porous structure allowing for unique design considerations for prototype and production thermoform tools. In contrast to sintered materials, the pores do not close off after machining allowing excellent definition and surface quality. 

METAPOR® – HD 100 AL is the high density grade of the material that is recommended for use in applications where the surface characteristics of the finished part are critical. HD 100 AL is specially formulated to have a smooth surface yielding better transparency on clear or translucent parts. The material is also recommended for use with acrylics and in twin-sheet applications.

Physical properties at 67°F (20 °C)

PropertyValue (Eng)Value (SI)
Density118.5 lb/ft31.9 g/cm3
Hardness Shore D8181
Flexural strength6,327 psi43.6 N/mm2
Flexural Modulus1,335 ksi9200 N/mm2
Impact strength5.2 ft-lb/in211 kJ/m2
Coefficient of thermal expansion
25 °C -125°C (77 – 257 °F)
19.8 x 10-6 in/in/°F36 x 10-6 mm/mm/°C
Thermal conductivity:
at 100°C (212 °F)
11.1 BTU/ hr-ft-°F20.5 W / m-°C
Martens Dimensional Stability226 °F108 °C
Mean pore diameter.0005 in12 µm
Total porosity (by volume)16%16%


pdf METAPOR Machining Guide (PDF)
pdf METAPOR Mold Construction Guide (PDF)

Users report the following advantages:

  • High Definition and Accuracy
  • Faster Air Evacuation
  • Improved Surface Quality
  • Reduced Machine Time
  • Trapped Air Elimination
  • Improved Mold Detail

Available Sizes
METAPOR® HD 100 AL is available in four standard sizes: 500L x 500W x 15/20/30/60 mm, (~19.7″ x 19.7 x 0.6/0.8/1.2/2.4″), and is cut into slabs of any required thickness. After the cutting process, the air permeability of the slab surface is reduced due to partial closure of the pores. It is essential to mill both surfaces of the slab by cutting off approx. 0.25 mm, (0.010″), providing complete air permeability.

Store dry and flat to protect against jolts, impacts and bowing. Avoid contact with grease and fluids.

The machining properties of METAPOR® are excellent and are comparable with rapid machinable aluminium. METAPOR®  must be machined dry and should not be in contact with any cooling liquids. In order to avoid any closure of pores, appropriate aluminium cutting tools must be used.  It is recommended to use dust extraction.  Avoid contact with grease and fluids.

Grinding and polishing of the machined surfaces can be made by hand or with a vibrating grinder. Use corundum paper with grains of 400 / 600 / 1200 in ascending order. METAPOR® must be polished dry and without any polishing paste!

Air Flow Rates
The numbers are average values for calculating air consumption for overpressure or under pressure applications. Specification is in liters per minute per cm2.

Pressure difference in bar (psi)Plate thickness in inchesPlate thickness in inchesPlate thickness in inchesPlate thickness in inchesPlate thickness in inchesPlate thickness in inchesPlate thickness in inchesPlate thickness in inches
0.2 (2.9)82.666.943.335.427.523.615.73.9
0.3 (4.4)98.382.651.147.235.427.519.77.9
0.4 (5.8)114.198.362.955.143.335.423.611.8
0.5 (7.3)129.8110.170.862.951.143.327.511.8
0.6 (8.7)149.5125.978.770.859.047.235.415.7
0.7 (10.2)165.2141.690.578.762.955.139.319.7
0.8 (11.6)180.9153.498.390.570.859.043.323.6
0.9 (13.1)196.7169.1106.298.378.766.947.227.5
1.0 (14.5)212.4180.9118.0106.286.570.855.131.5
2.0 (29.0)357.9314.6200.6184.9149.5129.898.362.9
3.0 (43.5)487.7428.7279.2251.7208.4180.9141.690.5
4.0 (58.0)601.7527.0346.1314.6259.6224.2177.0118.0
5.0 (72.5)696.1613.5401.2369.7302.8263.5212.4145.5
6.0 (87.0)774.8684.3448.4413.0338.2298.9239.9169.1