The Role of Nucleation in Solid State Reactions during Mechanical Alloying and Heat Treatment of High Energy Mechanically Milled Powders

The comparison of the phase transformations going on due to high energy ball milling (HEBM) and produced by pressure-less Direct Metal Laser Sintering (DMLS developed by EOS company) was carried out, by using an α-Fe, Ni and Cu3P powder mixture. It could be shown by X-ray diffractograms (XRD) of the two type of products, that by mechanical alloying a similar phase transformation occurs due to solid state reactions between the metal partners as in the case of laser sintering, in a given range of laser scanning speed in a laboratory laser equipment. According to the XRD evaluation the same metastable, γ-steel like phases were formed.

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Solid-state reactions between Cu and Al during mechanical alloying and heat treatment

Journal of Alloys and Compounds ◽

10.1016/s0925-8388(00)01094-x ◽

2000 ◽

Vol 311 (2) ◽

pp. 275-282 ◽

Cited By ~ 43

Author(s):

D.Y Ying ◽

D.L Zhang

Keyword(s):

Heat Treatment ◽

Solid State ◽

Mechanical Alloying ◽

Solid State Reactions

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TEM study of amorphization of Cu and Ti foils by cold-rolling

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100173868 ◽

1990 ◽

Vol 48 (4) ◽

pp. 146-147

Author(s):

W. A. Chiou ◽

N. L. Jeon ◽

Genbao Xu ◽

M. Meshii

Keyword(s):

Solid State ◽

Cold Rolling ◽

High Energy ◽

Rapid Quenching ◽

Vapor Condensation ◽

Metallic Alloys ◽

Solid State Reactions ◽

High Energy Particle ◽

Amorphous Metallic Alloys ◽

Thin Foils

For many years amorphous metallic alloys have been prepared by rapid quenching techniques such as vapor condensation or melt quenching. Recently, solid-state reactions have shown to be an alternative for synthesizing amorphous metallic alloys. While solid-state amorphization by ball milling and high energy particle irradiation have been investigated extensively, the growth of amorphous phase by cold-rolling has been limited. This paper presents a morphological and structural study of amorphization of Cu and Ti foils by rolling.Samples of high purity Cu (99.999%) and Ti (99.99%) foils with a thickness of 0.025 mm were used as starting materials. These thin foils were cut to 5 cm (w) × 10 cm (1), and the surface was cleaned with acetone. A total of twenty alternatively stacked Cu and Ti foils were then rolled. Composite layers following each rolling pass were cleaned with acetone, cut into half and stacked together, and then rolled again.

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Influence of V and Heat Treatment on Characteristics of WMoNbTaV Refractory High-Entropy Alloy Coatings by Mechanical Alloying

Coatings ◽

10.3390/coatings11030265 ◽

2021 ◽

Vol 11 (3) ◽

pp. 265

Author(s):

Chun-Liang Chen ◽

Sutrisna

Keyword(s):

Heat Treatment ◽

Mechanical Alloying ◽

Annealing Treatment ◽

High Energy ◽

304 Stainless Steel ◽

Homogeneous Distribution ◽

High Entropy Alloy ◽

Solid Solution Phase ◽

High Entropy ◽

Steel Substrates

Refractory high-entropy alloy (RHEA) is one of the most promising materials for use in high-temperature structural materials. In this study, the WMoNbTaV coatings on 304 stainless steel substrates has been prepared by mechanical alloying (MA). Effects of V addition and subsequent heat treatment on properties of the WMoNbTaV coatings were investigated. The results show that the RHEA coatings with nanocrystalline body-centered cubic (BCC) solid-solution phase were generated by the mechanical alloying process. The presence of the V element promotes a uniform microstructure and homogeneous distribution of composition in the RHEA coatings due to improving alloying efficiency, resulting in an increase of hardness. After the annealing treatment of the RHEA coatings, microstructure homogeneity was further enhanced; however, the high affinity of Ta for oxygen causes the formation of Ta-rich oxides. Annealing also removes strain hardening generated by high-energy ball milling and thus decreases the hardness of the RHEA coating and alters microstructure evolution and mechanical properties.

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