Formation Mechanism of Dilute Region and Microstructure Evolution in Laser Solid Forming TA15/Ti2AlNb Dual Alloy

TA15/Ti2AlNb multiple-layer samples and a dual-alloy sample were fabricated by laser solid forming (LSF) in this study. The formation mechanism of the dilute region and microstructure evolution of the dual alloy were analyzed. The results confirmed a “step” distribution of the composition among several initial layers in the multiple-layer samples, which can be explained by calculating the ratio of the remelted zone to the deposited Ti2AlNb zone in each deposited layer. However, the “step” compositional distribution disappears, and the compositional variation tends to be more continuous and smooth in the TA15/Ti2AlNb dual-alloy sample, which is attributed to alloy elements’ diffusion at the subsequent multiple re-melting and the longer thermal cycle. The macrostructure of the TA15/Ti2AlNb dual-alloy sample consists of epitaxially grown columnar prior β grains at the TA15 side and equiaxed grains at the Ti2AlNb side, while the microstructure shows a transition of α+β→α+α2+β/B2→α2+β/B2→α2+B2+O with increasing amounts of Ti2AlNb, leading to the microhardness also changing significantly.

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Microstructure evolution and mechanical properties of multiple-layer laser cladding coating of 308L stainless steel

Applied Surface Science ◽

10.1016/j.apsusc.2015.02.171 ◽

2015 ◽

Vol 340 ◽

pp. 143-150 ◽

Cited By ~ 54

Author(s):

Kaibin Li ◽

Dong Li ◽

Dongyu Liu ◽

Guangyu Pei ◽

Lei Sun

Keyword(s):

Mechanical Properties ◽

Stainless Steel ◽

Laser Cladding ◽

Microstructure Evolution ◽

Multiple Layer

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Microstructure evolution and microimpact performance of Sn–Ag–Cu solder joints under thermal cycle test

Journal of Materials Research ◽

10.1557/jmr.2010.0162 ◽

2010 ◽

Vol 25 (7) ◽

pp. 1312-1320 ◽

Cited By ~ 2

Author(s):

Y.L. Huang ◽

K.L. Lin ◽

D.S. Liu

Keyword(s):

Fracture Energy ◽

Microstructure Evolution ◽

Thermal Cycle ◽

Fracture Behavior ◽

Solder Ball ◽

Solder Joints ◽

Whisker Formation ◽

Structural Variations ◽

Before And After ◽

Ball Joints

The microstructure and microimpact performance of Sn1Ag0.1Cu0.02Ni0.05In (SAC101NiIn)/AuNi/Cu solder ball joints were investigated after a thermal cycle test (TCT). The joints show complete bulk fracture behavior before TCT. Moreover, TCT facilitated interfacial fracture behavior with lower fracture energy. The intermetallic compounds (IMCs) formed in the solder joints before and after TCT were investigated. TCT induces a variety of structural variations in the solder joints, including slipping bands, whisker formation, the squeezing of the IMC layer, the formation of cavities, the rotation and pop-up of grain, and the deformation and rotation of the entire joint. The variations in fracture behavior induced by TCT are correlated with the structural variations in the solder joints.

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Microstructure evolution and improved properties of laminated titanium matrix composites with gradient equiaxed grains

Science China Technological Sciences ◽

10.1007/s11431-020-1619-7 ◽

2020 ◽

Vol 63 (12) ◽

pp. 2687-2697 ◽

Cited By ~ 1

Author(s):

Shuai Wang ◽

LuJun Huang ◽

Shan Jiang ◽

Rui Zhang ◽

Qi An ◽

...

Keyword(s):

Microstructure Evolution ◽

Matrix Composites ◽

Titanium Matrix ◽

Titanium Matrix Composites ◽

Equiaxed Grains

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THE MICRO-REGION COMPOSITIONAL VARIATION OF Y1Ba2Cu3O9−x SINGLE PHASE SUPERCONDUCTOR

International Journal of Modern Physics B ◽

10.1142/s0217979287000220 ◽

1987 ◽

Vol 01 (02) ◽

pp. 231-236 ◽

Cited By ~ 1

Author(s):

Zhenhong Mai ◽

Liquan Chen ◽

Xi Chu ◽

Daoyang Dai ◽

Yongming Ni ◽

...

Keyword(s):

Single Phase ◽

Structural Phase ◽

Compositional Variation ◽

Interfacial Region ◽

X Ray Diffraction ◽

X Ray ◽

Compositional Distribution ◽

New Superconductor ◽

Phase Superconductor ◽

The Ideal

We have investigated the microstructure and compositional distribution of the Y 1 Ba 2 Cu 3 O 9−x single phase superconductor with scanning electron microscopy, energy dispersion x-ray spectrometry and x-ray diffraction. It has been found that the micro-region compositions are far front the ideal values, especially the yttrium content is quite higher than the suspected amount in the interfacial region. between crystalline grains. We propose that there might be another structural phase co-existed with the Y 1 Ba 2 Cu 3 O 9−x compound and it can not be distinguished from the main phase with diffraction methods. This phase would influence the properties, in particular the critical current density jc of the new superconductor.

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Micro-Nanostructure Formation Mechanism of High-Mg Al Alloy

Nanoscience and Nanotechnology Letters ◽

10.1166/nnl.2019.3016 ◽

2019 ◽

Vol 11 (10) ◽

pp. 1338-1348

Author(s):

Zeyi Hu ◽

Wenliang Liu ◽

Caihe Fan

Keyword(s):

Mechanical Properties ◽

Plastic Deformation ◽

Severe Plastic Deformation ◽

Formation Mechanism ◽

Microstructure Evolution ◽

Coarse Grained ◽

Al Alloy ◽

Nanostructure Formation ◽

Superior Mechanical Properties ◽

Alloy Strength

Micro-nanostructured materials have superior mechanical properties compared with coarse-grained materials. Severe plastic deformation (SPD) can effectively refine grains, resulting in the formation of typical micro-nanostructures. Fine grains improve alloy strength and toughness. This review summarizes the application of several typical SPD methods for high-Mg Al alloy. The effects of different SPD methods on the microstructure evolution, micro-nanostructure formation mechanism, and mechanical properties of the high-Mg Al alloy are analyzed in sequence. Finally, the development and future of the high-Mg Al alloy micro/nanostructure regulation are described.

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