Mating Material1. Type of material If stainless steels are used, martensitic types are preferable. Austenitic steels may be used but their low hardness must be taken into account. Unprotected carbon steels may through corrosion increase wear rate. In this case added lubrication could be used as corrosion protection. 2. Hardness When the load is near pmax the hardness of the mating surface is important. The harder mating material the better. A hard surface will always have a positive effect on bearing life and friction. As a general rule the mating material should be at least 100 HB harder than the bearing bronze. This gives the following recommended minimum hardness of mating material: A softer mating material than recommended will not necessarily endanger the function of the bearing, especially when the loads are moderate (<30% of pmax). In the offshore industry softer mating material than recommended in the table is often used with good results. In many applications Ni-coated surfaces with hardness as low as 220 HB are running against JM7 Ni-Al Bronze without problems.
3. Surface finish Recommended <1 Ra. |