How to choose a good stem nut?

Both to meet the strength and endurance;And to have excellent antifriction.When selecting the stem nut material, we should also consider the impact of environmental conditions on the material, that is, the stem nut should meet the bearing capacity (strength, elongation and endurance);The stem nut should have excellent corrosion resistance;Heat resistance;Excellent friction reduction.Poor lubrication of stem nut due to working conditions and planning reasons.Often in the semi-dry conflict or dry conflict in the case of work, so the selection of stem nut material to have excellent self-lubrication.