Normalizing Plates

[david339933]

How long should the soak time be for normalizing plates? Min. Temp is 1650F @ ????? minutes.

 

[metengr]

How thick are the plates??

 

[david339933]

1/2". I assumed 1hr/inch, but the majority of MTRs I see only have approx. 15 - 17 minutes.

 

[metengr]

The stated time is on the light side for complete austenization. I would have expected 30 minutes at least at temperature. There are no hard and fast rules on austenitizing, it depends on the furnace load and temperature color appearance (no shadows) before cooling in air. What are the results of the mechanical tests?

 

[david339933]

The mechanical tests is what I am struggling with. Material is SA-516-70 As Rolled, with coupons tested in both AR and Normalized conditions. Both conditions passed mechanical testing, however coupons were normalized for 1/2 hour (1hr/inch), while plate was only 15 mins.

 

[metengr]

I would try hardness testing for comparison. If they result in a minimum UTS that is above minimum, I see no issues.

 

[weldstan]

If you're only looking at tensile properties, I agree with metengr. Did the manufacturer normalize the test coupons or did you?

 

[david339933]

Yes, tensiles only. Manufacturer normalized coupons @ 1hr/inch.