Maraging 300 2

[mfgenggear]

Can you machinibility harden to 36 Hrc ?

As received from the material supplier the material is to soft.

 

[israelkk]

Yes, normally all steels up to 38RC can be machined. For exmpale gears can be hobed for up to 38RC. There are special tools that can machine evem 60RC.

 

[mfgenggear]

Israelkk

Thanks for your reply

However let me clarify what I am after.
I am interested for a Intermediate Heat treat prior to machining.
Can this material be age then temper any hardness like standard age harden stainless steels.
Then reheat treated for final hardness
This material is soft and tuff and is hard to machine
I want to machine ability harden for machining.
Most materials in the Normalized or/and annealed condition does not machine well because is to soft & gummy, does not lend itself to machine well.

 

[EdStainless]

How hard do you want it finished? I agree, harder would be easier to machine. You don't have as many heat treat options as with some age hardening alloys.

= = = = = = = = = = = = = = = = = = = =
Plymouth Tube

 

[mfgenggear]

so what are the options please advise?

 

[israelkk]

With the right cutting tools (probably more expensive than just standard cutting tools) it can be machined. Consult with manufacturers such as Iscar, etc. for the correct cutting tool speed and feed and the correct cutting tool type for machining marage 300 at the condition it received.

 

[mfgenggear]

However let me clarify what I am after.
I am interested for a Intermediate Heat treat prior to machining.
Can this material be age then temper any hardness like standard age harden stainless steels.
Then reheat treated for final hardness
This material is soft and tuff and is hard to machine
I want to machine ability harden for machining.
Most materials in the Normalized or/and annealed condition does not machine well because is to soft & gummy, does not lend itself to machine well.

This question was never answered does any one know?

 

[unclesyd]

There is no intermediate heat treatment for Mar 300 you essentially have what you have. Your material is supplied annealed/solution treated with a hardness of R_c 32. The only treatment mentioned is the aging treatment at 900F for a min of 3 hrs. The resulting hardness is R_c of 52-53.
We use this material to make high precision dies, lot of very small holes and I can't recall ever hearing any comments on machining difficulties.

You might give Allvac a call.

Look on page 2

http://www.allvac.com/pages/HTML/VascoMaxC.htm

 

[TVP]

unclesyd provided a good summary: there is no intermediate heat treating option for better machinability. Only options are machine in the solution treated condition, or in the fully hardened solution + aged condition. Have you considered hard turning/grinding/etc.?

 

[Robertmet]

Unclesyd, I'm glad to see someone uses it for more than golf clubs .That's about all you see if you Google Maraging steel !!The guys who developed it in the '60s weren't thinking about golf.For my thesis at that time I worked on a Mn maraging steel [ not Hadfield].

 

[mfgenggear]

Thanks for the replies

well then I am stuck, there are 2 parts, which are made for aircraft. qty of 100 ea with 5 & 6 diametral pitch gears which can only be shaped, it's killing the cutters.

I under estimated this materials toughness.

Turning & Milling is tough but manageable.
Gear shaping is an other issue.
, I will have to research further for better tooling.

Thanks

 

[israelkk]

This new information that the part is a gear raise questions. Why was such material selected for gears. As far as MMPDS-01 (MIL-HDBK-5J) the elongation of Marage 280 (300) for bars over 4 inch diamter in the trasverse direction is only 2%. To my opinion this is a bad choice for loaded gears.

 

[mfgenggear]

Israelkk

I can't give you a good answer.

These are my customers parts which are Design, Material & Stess Engineers. I can tell you this it's been flying.
:/

we are contracted to manufacture them.

the gears are nitrided.