Compressive yield strength of 4140 versus A2 tool steel hardened to RC 55-60

AISI 4140 Steel, oil quenched, 205°C (400°F) temper, 25 mm (1 in.) round = 220 kips yield (Rc 50-55)

That's as much as I'm going to look up for you., Now YOU follow up with a material search on MatWeb.

Brian Whatcott Altus OK

You can do it.

Hi Brian,

Thanks for your reply.

I will dig further into the matweb site and take a closer look.

I would like to find a cam material that has a compressive yield strength of 260,000 to 300,000 PSI after heat treatment. The cam rotates so slow I think the application could be considered static. My maximum Hertz contact stress is about 260,000 PSI.

I think I remember reading in Timoshenko's book on the strength of materials that hardened steel can handle Hertz contact stresses of over

450,000 PSI in static applications owing to the fact that at the center of the ellipse of contact, the material is compressed not only in the direction of the force but also in the lateral direction. I don't think it mentioned what type of steel or how hard. I do not presently have a copy of the book.

Thanks aga> >

What you are seeking is more related to Bearing Strength than Compressive Strength. Bearing Strength is usually substantially higher than Compressive Strength for most metals. For Example; for 4335V, Fcy is 198 ksi while Fby is 274 to 302 ksi. for H-11, Fcy is 260 ksi while Fby is 365 ksi for 250 Maraging steel, Fcy is 260 ksi while Fby is 354 ksi and one of my favorite very useful wide-property stainless is for PH13-8Mo, Fcy is 211 ksi while Fby is 356 ksi

Take a look at MIL-HDBK-5, they are all listed in there along with the statistical basis for properties and A and B values.

Thanks for the additional information Harry Andreas,

I found the MIL-HDBK-5 book you mentioned at this link...

That's one heck of a reference book !

You can download the 2003 version for free, and I guess they have a new updated version for a few hundred bucks.

Thanks again,

John

arry Andreas wrote:

There is a SANE or ASME spec that does that. I'll have to dig through some files at work to find a copy of it.

That should be in ksi (kips/in^2). Typo or something.

He gave the rod diameter, so I'm assuming he means yield tension, which would be in kips.

Don Kansas City

220 ksi is a standard strength for high strength alloy steels. The 25 mm (1 in) diameter is a heat treat thickness. Heat treating is more difficult for thicker parts. So the allowables are generally lower for thicker sections with everything else the same.

FYI: Here's a link to the where the data above came from.