Aluminum powders, powders and pastes are widely used as fillers in plastics; adhesives; construction adhesives and polymer cements; epoxy compositions; “Cold solders”; diamond grinding wheels.
Dispersed aluminum in the composition of these compositions protects them from drying out, does not allow the material to become brittle, protects against moisture and the damaging effects of sunlight.
The addition of aluminum powder to liquid and pasty adhesives increases their tensile strength and heat resistance; an additive to dense epoxy paste doubles the shear and tensile strength of the adhesive. This is due to a reduction in shrinkage, cracking and internal stress during curing.
Compositions for epoxy castings of a typical formulation (wt%): aluminum powder – 66.7; epoxy resin – 33.3; hardener – depending on the properties of the casting. Composition advantages:
- Increased dimensional stability, shrinkage in them by 35 rel. % lower compared to resin without filler;
- Improved machinability; increased thermal conductivity;
- Improved thermal stress characteristics; reduced coefficient of thermal expansion of the resin, which
- Especially valuable when bonding metal surfaces.
By means of casting in molds from such compositions, matrices, stamps and other types of products are made. The presence of fine alumininium paste and powder Malaysia in them reduces the carbonization of the resin when the matrix (die) is heated, reduces the shrinkage of the resin to about 0.1%, while the resin without aluminum powder can shrink up to 0.7% and even more.
The composition of the epoxy composition (wt.%): Aluminum powder – 13–19, ED-20 resin – 74–81, polyethylene polyamine – 6.0–7.5. They are used for fastening parts made of light metals, wood, plastics on products in the vertical plane, as well as for eliminating surface defects; possesses high painting properties, does not flow down from a vertical surface, has an impact strength of 5 kPa, withstands bending around a cylinder with a diameter of 10 mm.
Aluminum powders are used in the manufacture of a polymer base for the production of diamond grinding wheels, on which a thin layer of industrial diamonds is then applied. The use of aluminum reduces the number of operations for forming and processing wheels during their manufacture and improves heat removal from the diamond part during their operation. For more articles such as this one, click here.…