Good sliding properties of aluminum alloys in the zone of maximum friction, high fatigue limit, great temperature conductivity, easy machinability, and low cost are advantageous for wide usage even under very difficult operating conditions (at great static and dynamic loadings during low and high sliding speed).
The operating temperature is limited by the maximum constant allowable temperature of the lubricant used. For work at a higher temperature, consider alloy temperature expandability when determining the radial clearance.
Maximum loading ranges from 45 MPa to 50 MPa for a circumferential speed of1 m/sec. Maximum loads of up to 6 MPa is given for speeds of 10 m/sec. Surface textures for bushing and shaft sliding faces have a substantial effect on load capacity and life span of sliding mountings made from aluminum alloys. For that reason the surface texture of the bushing should be 0.4 microns and the sum of bushing and journal surface textures 0.6 microns at most.
We recommend to use high cutting speeds and tools with sintered carbonides when you machine aluminum alloys. Diamond tools are required for boring. Because of their finer structure, wrought alloys allow a smoother surface in comparison with cast alloys, and have lower values of friction factor in the zone of limiting lubrication.
For long life span for sliding mountings, use hardened shafts with a hardness of at least 250 HB. Because of the small absorbency factor of hard particles with aluminum alloys, the highest lubricant cleanliness is recommended.