6150 vs 4140 steel

[teclis22]

Hi All.

I hope i am posting this in the right forum.

Looking at the R.E.Davis tomahawk heads they offer two steels that are of interest : 4140 and 6150

the first having .4 carbon the later having .5

My general understanding so far was more carbon higher hardness. Googling for temper diagrams was not very successful and quite surprising :

http://www.fordtoolsteels.com/pdf/LSS_4140-4142HT.pdf

and:

http://www.nhml.com/embrittlement-of-steels.cfm

seems to suggest a temper at 350F / 180 C for a hardness of 57/58 HRc as the most you could reasonably hope to achieve from the steel.

Now for the 6150, i would expect a higher hardness, as it has higher carbon content but so far i was unable to verify that:

http://www.westyorkssteel.com/AISI_6150.html

seems to indicate that tempering at 350f/180C would only yield a 54HRc

http://www.integritysteel.com/aisi-6150-medium-carbon-chrome-vanadium-alloy-steel.html

Note the difference in temperatures and achievable hardness in the above link.
And even here a 350F temper would only yield a 58 HRC. compared to the 4140 thats 1 HRc at best.

6150 is the equal to 50CRv4 or 1.8159

http://www.mertens-stahl.de/fileadmin/user_upload/DrMertens/Datenblaetter/1.2241.pdf suggesting 54HRC again with a 350F temper


Check out here :

http://www.ims.it/ims/ims_spa/cmscontent.nsf/DocumentsByIDWeb/5RQMFR/$File/50CrV4.pdf


To say the least : i am confused.

the basic question was : what steel to choose 6150 or 4140 for a R.E.Davis tomahawk head. They seem to suggest the 6150 in their texts, but it seems the 4140 is the better choice and tempering it to 57/58 HRc and call it quits.

Hoping for feedback on this, as i would like to understand it.

Best regards to everyone

tec

P.S: link to the tomahawk head in question :http://www.hatchetsandaxes.com/patriot_faceted_bowl_pipe_tomahawk_steel_patriot_replica

 

[OTK]

I'll take the 6150.

 

[Sam Salvati]

4140 would be the better choice, based on having made tools from steels.

 

[stevomiller]

Honestly, I believe either would be fine. Both steels are used for making tough/impact resistant components. As for maximum hardness, what do you plan to use it for? If you want to throw it, no need (actually contra-indicated) to harden past the mid 50's.

 

[teclis22]

Hi all .

Thanks for the information. I appreciate the response.
Think i will go with the 4140 then to be on safe side. The internet seems more forth coming with information regarding heat treatment.

i actually wanted to use the hawk as a camping tool but now that you mention throwing .. that does seem tempting. What hardness do you recommend for that ? 55 Hrc ?

Best regards to all

 

[mete]

You see more comments about 4140 because it is a more common steel .It has many uses in many industries .A great combinatoin of properties , cost ,etc.. 55 HRc is stretching it a bit for that steel !

 

[hammerfall]

6150 is designed as type of spring steel i think. it is used for springs which demand heavy loads and higher impact toughness such as train and heavy trucks.