Compressive Deformation Behavior of the Ferritic Oxide Dispersion Strengthened Alloys at Elevated Temperatures

The compressive properties characterized as a function of the true stress-strain response of the ferritic oxide dispersion strengthened (ODS) alloys, fabricated by mechanical alloying, were examined at strain rates ranging from 0.01 to 0.5s-1. Based on the differential scanning calorimeter (DSC) analysis, the solidus temperature of the ferritic ODS alloys is 1446oC. Therefore, the compressive temperatures were chosen to be from 1050oC to 1300oC. Transmission electron microscopy (TEM) observation is indicative of the homogeneous distribution of the nano-yttria particles with the granularity of 100~200nm, which may exert a strong pinning effect on subgrains. The results indicate that flow stress of the ferritic ODS alloys enhances with decreasing compressive temperature and increasing strain rate. Investigation of the strain rate sensitivity exponent and apparent activation energy of the ferritic ODS alloys has been carried out in detail.

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Creep deformation behavior of nano oxide dispersion strengthened Fe–18Cr ferritic steel

Materialia ◽

10.1016/j.mtla.2020.100788 ◽

2020 ◽

Vol 12 ◽

pp. 100788 ◽

Cited By ~ 1

Author(s):

Rajesh Jarugula ◽

P. Suresh Babu ◽

S. Ganesh Sundara Raman ◽

G. Sundararajan

Keyword(s):

Creep Deformation ◽

Deformation Behavior ◽

Ferritic Steel ◽

Oxide Dispersion Strengthened ◽

Oxide Dispersion ◽

Nano Oxide

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Microstructure, strengthening mechanisms and hot deformation behavior of an oxide-dispersion strengthened UFG Al6063 alloy

Materials Characterization ◽

10.1016/j.matchar.2012.10.007 ◽

2013 ◽

Vol 75 ◽

pp. 108-114 ◽

Cited By ~ 28

Author(s):

H. Asgharzadeh ◽

H.S. Kim ◽

A. Simchi

Keyword(s):

Hot Deformation ◽

Deformation Behavior ◽

Oxide Dispersion Strengthened ◽

Oxide Dispersion ◽

Strengthening Mechanisms ◽

Hot Deformation Behavior ◽

Al6063 Alloy

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Selective Laser Melting of Oxide Dispersion Strengthened Steels

ASME 2011 Pressure Vessels and Piping Conference: Volume 6, Parts A and B ◽

10.1115/pvp2011-57892 ◽

2011 ◽

Cited By ~ 1

Author(s):

Thomas Boegelein ◽

Ashwin Rao ◽

Andrew R. Jones ◽

Gordon J. Tatlock

Keyword(s):

Selective Laser Melting ◽

Elevated Temperatures ◽

Prolonged Exposure ◽

Steel Substrate ◽

Oxide Dispersion Strengthened ◽

Nickel Base Superalloy ◽

High Temperature Strength ◽

Oxide Dispersion ◽

Laser Melting ◽

Ods Alloys

Oxide Dispersion Strengthened (ODS) alloys are a long established class of materials manufactured using powder metallurgy techniques. These alloys can offer exceptional high temperature strength and resistance to radiation damage, thus are envisioned to be used in a number of future nuclear and fossil energy power applications. However, due to the manufacturing steps involved, the overall cost to build components with these materials can be high. This paper presents work conducted to assess the feasibility of applying Selective Laser Melting (SLM) techniques to either coat or direct build on substrates with Fe-based Oxide Dispersion Strengthened (ODS) alloys. SLM is a rapid prototyping technique which can be used to manufacture near net-shape solid components from layered metallic powder beds. Two different geometries were of interest in this study — a simple button configuration with a nickel-base superalloy (IN939) substrate and a more complex hexagonal shaped wall with a mild steel substrate. Powders of PM2000 (a FeCrAl based ODS alloy) were deposited in both cases. Heat treatments were subsequently conducted on these structures to investigate effects of temperature on the bond characteristics and secondary recrystallisation. Electron microscopy examination revealed significant amounts of diffusion between the nickel and the ODS powders which enhances the bond strength. The studies have revealed the existence of a strong bond between the substrate and the interface even after prolonged exposure at elevated temperatures.

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Mechanical Properties of Discontinuous SiC Reinforced Aluminum Composites at Elevated Temperatures

Journal of Engineering Materials and Technology ◽

10.1115/1.3226033 ◽

1988 ◽

Vol 110 (2) ◽

pp. 77-82 ◽

Cited By ~ 115

Author(s):

T. G. Nieh ◽

K. Xia ◽

T. G. Langdon

Keyword(s):

Mechanical Properties ◽

Room Temperature ◽

Elevated Temperatures ◽

Aluminum Matrix ◽

Oxide Dispersion Strengthened ◽

Dislocation Motion ◽

Particulate Composites ◽

Oxide Dispersion ◽

Aluminum Composites ◽

High Temperature Mechanical Properties

High temperature mechanical properties of discontinuous, whisker and particulate, SiC reinforced aluminum composites, including 2124 and 6061 alloy matrices, are reviewed. It is shown that the behavior of these composites is similar to conventional oxide dispersion strengthened alloys. Namely, they exhibit a low strain rate senstivity and a high apparent activation energy for creep deformation. Despite the fact that the addition of SiC significantly improves the mechanical properties of aluminum at room temperature, the mechanical strength of the composite at elevated temperatures is dominated by the strength of the aluminum matrix This is because the SiC dispersoids are, in general, too coarse and they are not effective barriers for dislocation motion. It is also demonstrated that SiC particulate composites are less creep resistant than SiC whisker composites.

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