Applications of Bronze Sintering

Parts made from sintered bronze are widely used in heavy industry to make bearings, bushings, and wear plates. Less known applications of sintered bronze include cartridge filters and pneumatic mufflers.

In this post, let us see how some of these parts are manufactured.

Manufacturing of floating bearings

Sintered bronze can be used for making floating bearings. Along with bronze, the bearing material also contains titanium and some metal from groups VI, VII and VIII of the periodic table in a proportion of 4 to 15% w/w as an additive for increasing stability. 

Furthermore, graphite is used as a solid lubricant present in the proportion of 12 to 20% b.w.

The material is pressed, sintered and calibrated obtaining a final product with a lower weight than the known sintered lead bronze anti-friction material. The finished product has a satisfactory friction value with a high resistance.

More information is available in this patent.

Manufacturing of bronze-steel clad

Bronze-steel clad can be manufactured by sintering bronze alloy powder on a steel back metal, then sintering the resultant mixture to obtain a bilayer material having a porous bronze alloy layer on the steel. The thickness of the layer is about 1-4 mm. 

Finally, the obtained bilayer is dry-rolled and sintered so that the bronze alloy layer has a porosity of 3% or less. During the above process, rolling oil is supplied to the surfaces of rolling rolls.

For more details refer to this patent.

Sintered bronze bearing with improved wear resistance

A bronze bearing can be made by first mixing copper tin and bismuth alloy powder with a metal compound powder of Fe3P and MoSi2 with average particle size less than 10 μm.

Then the mixture is heated to a high temperature and solidified by bonding the sintered powder mixture to a steel backing. A rolling pressure is applied to reduce the porosity of the sintered powder and produce a fully-dense sintered bearing compact.

The copper, tin and bismuth alloy powder forms islands spaced from one another by the matrix and the metal compound powder is dispersed throughout the matrix.

More information is available on this patent.

Surface defects reduction of sintered bronze

Surface defects in laser sintered bronze occurs due formation of crevices and internal passage while forming a sintered layer of powdered particles. 

These defects can be reduced by applying a braze material (nickel, gold, or silver alloy) to the surface. The braze material is heated such that it melts and wets the internal surface. The braze material consolidates through capillary forces, filling the crevices to create a cladding layer that completely fills the crevices in the internal surface and makes the surface smoother.

For more details refer to this patent.

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