Heat treatment versus properties studies associated with the Inconel 718 PBF acoustic filters

Conference · Mon Feb 24 04:00:00 EDT 1975

OSTI ID:4152217

Smolik, G R; Reuter, W G

PBF acoustic filter Unit No. 1 cracked when heat treatment was attempted. The effects of prior thermal cycling, solution anneal temperature, and cooling rate from solution anneals were investigated. The investigations concerned influences of the above variables upon both 1400$sup 0$F stress rupture solution- annealed properties and room temperature age-hardened properties. 1400$sup 0$F stress rupture properties were of interest to assist the prevention of cracking during heat treatments. Room temperature age-hardened properties were needed to ensure that design requirement would be provided. Prior thermal cycling was investigated to determine if extra thermal cycles would be detrimental to the repaired filter. Slow furnace cools were considered as a means of reducing thermal stresses. Effects of solution annealing at 2000 and 1900$sup 0$F were also determined. Test results showed that slow cooling rates would not only reduce thermal stresses but also improve 1400$sup 0$F ductility. A modified aging treatment was established which provided the required 145 ksi room temperature yield strength for the slowly cooled material. Prior cooling did not degrade final age-hardened room temperature tensile or impact properties. (auth)

• Research Organization: Aerojet Nuclear Systems Co., Sacramento, Calif. (USA)
• NSA Number: NSA-33-007813
• OSTI ID: 4152217
• Report Number(s): CONF-750574--1
• Country of Publication: United States
• Language: English

Related Subjects

*INCONEL 718-- MECHANICAL PROPERTIES
*PBF REACTOR-- FILTERS
360103* --Materials--Metals & Alloys--Mechanical Properties
AGING
ANNEALING
CRACKS
DUCTILITY
HEAT TREATMENTS
N50230* --Metals
Ceramics
& Other Materials--Metals & Alloys--Properties
Structure & Phase Studies
RUPTURES
SOUND WAVES
THERMAL CYCLING
YIELD STRENGTH