Heat Treat of 1045 material

[Dobe]

I have been playing around with heat treating 1045 material. I have gotten good results by raising the oxygen analizer to 66%. But I cannot explain why this works? I am trying to obtain a finished Rc25-32 after quench and finish machine off .015 machine stock.

 

[redpicker]

I am not sure what you mean by "raising the oxygen analizer to 66%", but if you are affecting the furnace atmosphere, you are also affecting the scale on the parts during quenching, and for a shallow hardening steel like 1045, any difference in the surface of the part will affect the effectiveness of the quench.

rp

 

[unclesyd]

Are you sue your are using O2 not N2 or CO.
I agree with the above post that your level of O2 would be a
problem in big way. Not only would scale but decarozation and you you could have metal ignite at your stated O2 level. If this is N2 these levels will eventually be problem due to nitriding of the elements.

 

[TVP]

Dobe,

Please provide some basic process details, like furnace vs. induction heating, the type of quenching, etc.

 

[Dobe]

I am stress relieving at 1100 degrees and I added a normalize at 1650 degrees. We have 2 electric atmoshpere furnaces (nitrogen/methonal). I stack 5 pieces that have been rough machined on a fine edge so the atmospere can get around the sides of the part at a temperature of 1550 degrees. Time in the furnace is dictated by the height of the stack. They are then quenched in oil, which is set between 125-140 degrees for 40 seconds. Then put in a pre draw drawer and then in a draw furnace at a temp dictated by the hardness, between 900 to 1000 degrees. I have found the normalize operation to help stabalize and I get a better std. deviation after draw. The highest I have had the oxygen analyzer was at .75%.

 

[unclesyd]

Here is about all you can do with 1045 steel. European Designation but the same stuff.

http://www.trafilix.com/en_pdf/C45E.pdf