I want to select material for a pin operating at 550C. It is simple pin joint with pin under shear load. Please suggest suitable material for this application.
First, you need more information to select a proper material. What is the pin diameter being considered and shear loading on the pin? Is this elevated temperature in air or other service environment?
Is your recommendation based on the low shear stress and assuming a service life that is somewhat short? In general, this temperature usually calls for a higher alloy concentration for creep strength and resistance to graphitization and spheroidization. Thanks for any added basis for the selection.
CoryPad
Yes. The relatively low shear load on the pin at 1020 deg F should allow acceptable use of this material at reasonable service life, with lowest cost. Upgrades in material could include ASME SA 193 Grade B16 material similar to 4140 with vanadium for elevated temp strength and creep strength or further upgrade to 410 ss.
CoryPad
The 4140 steel can be used with no creep concerns to 1000 deg F because of the Mo and Cr contents. Recognizing that the service temperature is 1020 deg F versus 1000 deg F should still afford a good service life. I don't see any graphitization concerns because the Cr content is above 0.50% by mass. So, given the low stress in service this should be acceptable, as a minimum.
The high temperature limit for the 410 stainless steel will depend on creep/stress rupture, which depends on service stress. Here is a link to Carpenter and 410 stainless steel;
One more query
In my application the material is heated to 550C and kept for 50 hours then cools to room temperature(heating and cooling will be done at 25C/hr). It undergoes approx. 500 such type of cycles. Will it degrade the properties of ss410? Please suggest heat treatment temperature
Maui,
I have not worked out on exact hardness requirement, the pin joint has to work for approximately 500 times.
Per the information supplied by the link provided, the 410 stainless steel should be supplied in the quenched and tempered condition for maximum elevated temperature performance. Temper for 1 hour at 1125 deg F.
A hot work tool steel such as H13 should work quite well in this application. It was designed for use at elevated temperatures and is relatively inexpensive. If a hardness of 50 HRC or less is acceptable, then the tempering temperature for H13 will be 1050F or higher. So exposures to temperatures of 1025F should not be a problem. You can read about the properties this grade possesses in the following link: