Hardness for 50 mm dia. shaft in 1045

[cedeng]

I need to know the best hardness for my industrial 50 mm diameter shaft in AISI 1045 material. I don't wanna be too hard because I don't need strenght, I need wear resistance (with the key).

I was thinking around 30 HRC. Is it too brittle ?

Cedric

 

[Carburize]

1045 normalized at 1650 then water quenched from 1525-1550 followed by a 2 hour temper at 1000 should give a hardness of around 30HRC combined with reasonable toughness.

 

[ornerynorsk]

Why not use hardchrome shaft, in which the base mat'l is normally 1045. Then you also have some corrosion resistance and some precision sizing to boot.

 

[unclesyd]

Take a look at this site.

http://www.seshafting.com/services.html

 

[TVP]

30 HRC will not provide very good wear resistance. As ornerynorsk points out, 1045 that has hard chromium plating is often used when wear resistant shafts are required. The shaft is usually surface hardened to at least 450 HV (~ 45 HRC) and then chrome plated.

 

[metengr]

Just a thought, if you intend to hard chrome plate after heat treatment (surface) to increase the strength of this material you might want to consider a post bake operation at 500 deg F to remove any effects of dissolved hydrogen from plating.

 

[Cockroach]

In general, AISI 1045 is commercially available as HRc 18-22. You can heat treat, the quench and temper for elevated hardness, typically HRc 28-32.

What I have done quite often in the back shop is to flame harden the shaft by simply applying heat via a tiger torch. Let the shaft become cherry red, then quickly submerge it into a bucket of ordinary motor oil, say SAE 10/40. Be sure to stir the motor oil while the shaft is submerged, i.e. no peaking, air will tend to ignite the oil, which was my last mistake!

You will find the wear to be sufficiently addressed using flame hardening methods.

Kenneth J Hueston, PEng
Principal
Sturni-Hueston Engineering Inc
Edmonton, Alberta Canada