High chrome grade similar to 420 2

[NickE]

I have a print with Worknorm 1.4122 on it the chemistry is as follows:

0.33-0.45   C:Carbon
=1.00      Mn:Manganese (nominal?)
=1.00      Si:Silicon  (nominal?)
 0.04       P:Phosphorus (max?)
0.015       S:Sulfur (max?)
15.5-17.5  Cr:Chrome
0.80-1.30  Mo:Molybdenum
 =1.00     Ni:Nickel (nominal?)

X35CrMo17 DIN

I am not able to find a common USA grade of SS that can fit this chemistry. The part is a sort of spring clip so it seems that I need a martensitic grade, however the Cr content in the above is much higher than in the martensitic grades like 420. I would like to avoid sugesting a PH stainless as there is no forming involved. Is there a high chrome grade similar to 420, or alternately is there an american grade I should recommend?

Thanks In advance.
nick

 

[metengr]

Nicke;
What is the specific application because depending on service you have several martensitic stainless steel choices;

Carpenter or Allegheny Ludlum 440A , which has the chrome range but less Mo and nickel at 0.5%.

Carpenter Type 431 - which has the chrome range, less carbon, and slightly higher nickel, no moly

Allegheny Ludlum Type 425 Mod - lower chrome range (13-14), Mo within range, nickel at 0.5%, carbon at 0.5-0.55%


Other than the slightly lower chromium range, it would appear that the Allegheny Ludlum Type 425 Mod is a close match, especially for the carbon range.

 

[NickE]

I think that the large amount of extra Carbon and the lack of Ni eliminates the 440A from consideration. (I also dont think that my diemaker wants to hit .025" 440A at full hardness)

I noticed the 425Mod, I'm worried that the lower Cr, combined with the higher C and lower Ni will not provide the customers required corrosion resistance.

This is just a "make to print" quote. I've got really no information on operating environment.

So now I have a new question:

Will ~2.5-3.5% lower Cr, ~.1% higher C, and ~.5% less Ni cause a significant change in the corrosion resistance of a spring tempered part?

Thanks metengr

nick

 

[richardbuss]

Hi Nick,

why dont you just use 1.4122 material ?

Best Regards
Richard Buss

 

[israelkk]

AISI 410 comes in flat forms such as strip and sheet and is used for springs. Many years ago I used AISI 410 sheet to design and produce a part for an aircraft engine using metal spining process. As far as I recall AISI 420 comes as bars and not as sheet, but I may be wrong.

 

[NickE]

Richard Buss- I think that we'll have a real hard time purchasing prototype and production quantities of 1.4122 in the US. (If you know of a source please advise)

Israelkk- We currently use signifcant amounts of a modified 420 in coil form. (note designated as 7C27Mo2 by Sandvik MT) Its a 420SS with a moly addition to provide better corrosion resitance and fatigue strength in mildly corrosive atmospheres.

Thanks guys.
nick

 

[TVP]

Why not quote the Sandvik material, as it is fairly close? FYI, the Ni, Mn, & Si levels are 1.00% maximum, not nominal.

 

[NickE]

Thanks TVP I wondered what the equals sign means... Data on Worknorm #'s from this site:

http://mdmetric.com/tech/matnr2.htm

Since the Sandvik mtl. is so close and we use so much of it Thats what I will reccommend to the Project Eng. After that if our customer will approve the print change then we will sail through....

Thanks and stars round....

nick

 

[richardbuss]

Hi Nick,

although my company is in Germany we produce and stock 1.4122. Let me know what size you need and ill give you a price indication to the US.

website is

http://www.doerrenberg.de

e-Mail richard.buss@doerrenberg.de

regards
Richard