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...I believe that two different steels, one hard, one soft will have a lower coefficient of friction than two similar steels...If you don't like bronze bushes, try cast iron.
If you use free machining steel for the Pins together with some steel which gives you ä good finish when reaming it should last for quite long - at least if you lubricate those joints from time to time.Why free machining steel? Because they are made to have good Chip control and to keep Tool wear low if poasible. So for example those Grades that contain lead will have some kind of "dry lubrication" because of the lead.