At the hardness level for a 700 MPa YS carbon steel, the metal-to-metal wear resistance (unlubed) is not good based on my tests on 4130 (not 4140). At this hardness level, carbon is not so important, so 4130 is an appropriate reference alloy. Direct comparison with 17-4PH in all heat treat...
EDi,
What size is the part? What is mating alloy? Any lube or surface coatings? How fabricated: casting, machined part? What YS needed? Is it for load carrying ability or wear resistance. 300 series Stainless can be "soft" but have better wear properties/life. Just substituting a similar SS...
EdStainless is right on the money! PH13-8Mo was developed for just such strenuous service requiring strength/toughness/some corrosion protection...the downside - higher cost due to its processing requirements. It is widely used in aircraft/space components. Sharp corners/notches can have a...
enginesrus
The Nitronic alloys are available up to 12-14" dia in the annealed condition with a minimum YS=50 ksi. To match the 17-4PH alloy, the Nitronics have to be warm or cold worked which limits their size availability depending on the producer's capability. I do want to clarify one thing...
17-4PH has poor unlubricated galling and wear properties mated to itself and other "poor" alloys not designed for this type service. It had done well over the years as chrome plated or nitrided. I have tested Al Bronze (Ampco 18) and found it exceptional for galling (ASTM G98) and also...
Armco, the original developer of this alloy, warned against using it in Cond. A (as you call annealed) especially in bar and larger section sizes. However, subsequent testing showed this condition did not have "bad" properties and had strength similar to H1100. Since these are small stampings...
Just joined today but found this thread of interest. Hope it's not too late but this info could be helpful to others down the road.
Nitronic 50 (N50), has a machinability index that falls between 316 and Nickel base alloys. It does take special care to minimize distortion and does work harden...
