Zinc Bearing alloys
compared to Bronze bearing alloy C93200:
An investigation of the properties of ZA alloys as bearing
materials was conducted in 1981 - 1986.
It was concluded that ZA bearing alloys had equivalent or superior bearing
performance to bronze alloys, particularly C93200 (SAE 660) lead-tin bronze.
Experimental data demonstrated that ZA bearing alloys have the following
advantages over SAE 660:
Zinc alloy bearings typically run with
lower friction energy loss and at lower temperatures than C93200 Bronze
bearings under identical conditions of load, speed and journal.
The load capacity of ZA bearings is
equivalent or higher than for C93200 bronze bearings, particularly at higher
speeds. Further, hydrodynamic
behavior is extended to higher load in ZA bearings than in C93200 Bronze at
equivalent bearing speeds.
The wear rate of ZA alloys is
equivalent to or often much lower than C93200 Bronze under the same conditions
of load and speed.
ZA alloys are hard in comparison to lead-tin bronzes but equivalent to
aluminum bronze. Their
conformability (ability to deform to accommodate journal misalignment) is
better than bronze in view of the lower melting point of the alloys and the
reduction in hardness with bearing temperature.
Embeddability is also excellent and is comparable to C93200 bronze.
However, as with all bearing materials, efforts should be exercised to
prevent ingestion of larger dust or metallic particles which could result in
rough running and wear of the bearings.
Running: The lubrication
starvation or emergency running properties of ZA alloys are superior to
lead-tin and aluminum bronzes. During
such conditions, a thin film of zinc is smeared across the interface with the
journal, thereby reducing friction and wear on the shaft.
For more detailed information regarding zinc bearing
applications, or to request the zinc design manual, please contact Ryan Winter
at 845-427-2151 or firstname.lastname@example.org