On the microstructure and high cycle fatigue of near-net shape PM-HIPed Inconel 625 [Elektronisk resurs]

• This paper investigated the microstructure and fatigue behavior of PM-HIPed Inconel 625. The microstructure was composed of γ phase and (Mo, Nb) carbonitrides located mostly on prior particle boundaries. Despite the presence of these carbonitrides, the samples showed good tensile properties with high elongation. Two different surface conditions, pickled and machined, were used for high cycle fatigue testing under a four-point bending test. The results indicated that pickled samples had 6% lower fatigue strength (at 106 cycles) with three times higher standard deviation compared to the machined ones. Fatigue failure mechanisms were found to be dependent on surface conditions and showed different failure modes due to non-metallic oxide inclusions and surface defects in samples with machined and pickled surfaces, respectively. The effect of type, size, and location of defects, multiplicity of crack initiations, as well as surface roughness were analyzed and discussed. 

Ämnesord

Engineering and Technology  (hsv)

Materials Engineering  (hsv)

Manufacturing, Surface and Joining Technology  (hsv)

Teknik och teknologier  (hsv)

Materialteknik  (hsv)

Bearbetnings-, yt- och fogningsteknik  (hsv)

Materialteknik  (kau)

Materials Engineering  (kau)

Materials Science  (kau)

Materialvetenskap  (kau)

Genre

government publication  (marcgt)

Indexterm och SAB-rubrik

Fatigue properties

Inconel 625

Mechanical properties

Microstructure

Surface roughness

Carbon nitride

Failure (mechanical)

Fatigue testing

High-cycle fatigue

Niobium compounds

Surface defects

Fatigue behaviour

Four-point bending test

High cycle fatigue

High cycle fatigue testing

High elongation

Near net shape

Prior particle boundaries

Surface conditions