Grain size and particle dispersion effects on the tensile behavior of friction stir welded MA956 oxide dispersion strengthened steel from low to elevated temperatures

In order to clarify the influence of milling time on the atomized precursor powders for 9Cr-ODS (Oxide Dispersion Strengthened) steel, the morphology and microstructure of atomized powders and mechanical alloying (MA) powders with different milling time were investigated by scanning electron microscopy (SEM), laser diffraction particle size analyzer, X-ray diffraction (XRD) and Vickers-hardness tester. The experimental results showed that the atomized powders are spherical in shape with the particle size of ~ 47 μm and the grain size of ~ 2 μm. With the increase of MA time, the morphology of MA powders becomes from spherical to lamellar structure, then to equiaxed shape. The mean powder size increases firstly then decreases. The grain size decreases quickly at the initial stage of milling process (0-2 h) then trends to reach a saturation value. The Vickers-hardness increases rapidly at the initial stage of milling, then reaches a saturation value.

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Oxide Particle Growth During Friction Stir Welding of Fine Grain MA956 Oxide Dispersion-Strengthened Steel

Metallurgical and Materials Transactions E ◽

10.1007/s40553-016-0101-1 ◽

2017 ◽

Vol 4 (1) ◽

pp. 1-12

Author(s):

Brad W. Baker ◽

Keith E. Knipling ◽

Luke N. Brewer

Keyword(s):

Friction Stir Welding ◽

Oxide Particle ◽

Oxide Dispersion Strengthened ◽

Particle Growth ◽

Oxide Dispersion ◽

Oxide Dispersion Strengthened Steel ◽

Friction Stir ◽

Fine Grain

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Influence of friction stir welding conditions on joinability of oxide dispersion strengthened steel / F82H ferritic/martensitic steel joint

Nuclear Materials and Energy ◽

10.1016/j.nme.2016.09.018 ◽

2016 ◽

Vol 9 ◽

pp. 367-371 ◽

Cited By ~ 8

Author(s):

Hisashi Serizawa ◽

Masakazu Murakami ◽

Yoshiaki Morisada ◽

Hidetoshi Fujii ◽

Shuhei Nogami ◽

...

Keyword(s):

Friction Stir Welding ◽

Martensitic Steel ◽

Oxide Dispersion Strengthened ◽

Oxide Dispersion ◽

Oxide Dispersion Strengthened Steel ◽

Friction Stir ◽

Steel Joint

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ODS EUROFER Steel Strengthened by Y-(Ce, Hf, La, Sc, and Zr) Complex Oxides

Metals ◽

10.3390/met9111148 ◽

2019 ◽

Vol 9 (11) ◽

pp. 1148 ◽

Cited By ~ 2

Author(s):

Roman Husák ◽

Hynek Hadraba ◽

Zdeněk Chlup ◽

Milan Heczko ◽

Tomáš Kruml ◽

...

Keyword(s):

Grain Size ◽

Yield Strength ◽

Complex Oxides ◽

Oxide Dispersion Strengthened ◽

Interparticle Spacing ◽

Oxide Dispersion ◽

Strengthening Effect ◽

Dispersion Strengthening ◽

Doping Element ◽

Average Grain Size

Oxide dispersion-strengthened (ODS) materials contain homogeneous dispersions of temperature-stable nano-oxides serving as obstacles for dislocations and further pinning of grain boundaries. The strategy for dispersion strengthening based on complex oxides (Y-Hf, -Zr, -Ce, -La) was developed in order to refine oxide dispersion to enhance the dispersion strengthening effect. In this work, the strengthening of EUROFER steel by complex oxides based on Y and elements of the IIIB group (lanthanum, scandium) and IVB group (cerium, hafnium, zirconium) was explored. Interparticle spacing as a dispersoid characteristic appeared to be an important factor in controlling the dispersion strengthening contribution to the yield strength of ODS EUROFER steels. The dispersoid size and average grain size of ODS EUROFER steel were altered in the ranges of 5–13 nm and 0.6–1.7 µm, respectively. Using this strategy, the yield strength of the prepared alloys varied between 550 MPa and 950 MPa depending on the doping element.

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