Investigation Of Axial Loading Fatigue Properties Of Heat Resistant Alloy N-155 Part 2. An Exploratory Investigation Of The Effect Of Temperature, Time, And Stress On Fracture Characteristics And Metallographic Structure Of N-155 And Hardness Of N-155 And

Item

Title
Investigation Of Axial Loading Fatigue Properties Of Heat Resistant Alloy N-155 Part 2. An Exploratory Investigation Of The Effect Of Temperature, Time, And Stress On Fracture Characteristics And Metallographic Structure Of N-155 And Hardness Of N-155 And
Date
1953
Index Abstract
Online
Photo Quality
Complete
Report Number
WADC TR 52-226 Part 2
Corporate Author
University Of Minnesota
Laboratory
Materials Laboratory
Extent
41
PB Number
PB116828
NTRL Accession Number
AD016377
Identifier
AD0016377
AD Number
16377
Access Rights
Notice(s)
Distribution Classification
1
Contract
AF 33(038)-18903
DoD Project
None Given
DoD Task
None Given
DTIC Record Exists
Yes
Distribution Change Authority Correspondence
AFAL LTR
Distribution Change Action Date
1/1/1900
Distribution Conflict
Fix
Index Price
$2.75
Index In
U.S. Government Research Reports, vol. 23, no. 5, p.174-175, 5/20/1955
Abstract
Microscopic analysis of the fracture profiles of N-155 specimens indicated that the tendency for an intercrystalline fracture to occur increased with time and decreased with increasing stress and stress ratio. Investigation of the metallographic structure and hardness of unstressed N-155 material exposed to 1350 deg and 1500 deg F for various lengths of time from 4 to 4000 hr disclosed a precipitation hardening as an important structural transformation. Hardness measurements confirmed this conclusion. The effect of stress and stress ratio on the metallographic structure and hardness was investigated. Stress appeared to exert a more pronounced effect on hardness than on metallographic structure; cyclic stress did not significantly accelerate the microscopically visible general matrix precipitate. Rockwell B hardness tests were conducted on both the surface and longitudinal sections of the stressed specimens in the longitudinal variable stress regions. The N-155 as well as the S-816 specimens displayed a hardening effect which increased with increasing stress and appeared to reach a maximum. Tukon Vickers diamond-pyramid hardness tests were also conducted on transverse sections of rotating beam fatigue specimens in the transverse variable stress regions. (See also AD-13052)
Report Availability
Full text available
Date Issued
1953-02
Provenance
IIT
Type
report
Format
1 online resource
Creator
De Money, Fred W.
Media
WADCTR52-226part02.pdf