Austempering A-2 (without salts)?

[F. Allin Kahrl]

Can it be done with heated aluminum plates instead of a liquid bath? I figure I'd do a normal austenitizing recipe in the furnace while heating the quench plates up to about 490º in the oven. Then pull the austenitized blade(s) out of the furnace, press 'em till just below visible heat, and throw them in the 490º oven and cook 'em over night.

Does that make sense? Would that produce lower bainite like I hope it would, or just make a mess?

-Allin

 

[mete]

To find if a steel is suitable for austempering you have to look at the TTT diagram. When you look at the one for A-2 you will find that you would need about 450F but it would take about 100 HOURS to complete the transformation to bainite !!! .Are you a patient man ? The plate idea is ok since you have 10 minutes to get down to 450F.Not every steel is good for bainite .