The role of microstructural characteristics of additively manufactured alloy 718 on tool wear in machining

The role of bismuth (50 to 9000 ppm) and calcium (50 to 200 ppm) additions on the microstructural characteristics in Sr-modified 319 alloys (with/without 0.4 wt% Mg addition) were investigated using optical and electron microscopy, and image analysis. It was found that the modification effect of Sr continuously diminished with Bi addition up to ~3000 ppm Bi; further Bi addition led to the modification of the Si particles due to the presence of Bi. In the Ca-containing alloys, a coarse eutectic Si structure resulted with Ca additions of 50 ppm, due to the formation of Alx(Ca,Sr)Siy compounds. Increased Ca additions (up to 200 ppm) did not alter the Si particle size. The Alx(Ca,Sr)Siy phase particles appeared in rod-like form in the Sr-modified alloys and in plate-like form in the 319+0.4 wt% Mg alloys. MgO, Al2O3, and AlP particles appear to act as nucleants for the precipitation of the plate-like Alx(Ca,Sr)Siy phase.

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The role of synthesis pathway on the microstructural characteristics of sulfur-carbon composites: X-ray imaging and electrochemistry in lithium battery

Journal of Power Sources ◽

10.1016/j.jpowsour.2020.228424 ◽

2020 ◽

Vol 472 ◽

pp. 228424 ◽

Cited By ~ 2

Author(s):

Daniele Di Lecce ◽

Vittorio Marangon ◽

Wenjia Du ◽

Dan J.L. Brett ◽

Paul R. Shearing ◽

...

Keyword(s):

Lithium Battery ◽

Carbon Composites ◽

Microstructural Characteristics ◽

X Ray ◽

X Ray Imaging

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Microstructure and Recording Noise of Thin Film Longitudinal Media

MRS Proceedings ◽

10.1557/proc-232-3 ◽

1991 ◽

Vol 232 ◽

Cited By ~ 15

Author(s):

Tadashi Yogi ◽

Thao A. Nguyena ◽

Steven E. Lambert ◽

Grace L. Gorman ◽

Gil Castillo

Keyword(s):

Thin Film ◽

Film Growth ◽

Magnetic Layer ◽

Deposition Condition ◽

Growth Morphology ◽

Microstructural Characteristics ◽

Magnetic Layers ◽

The Media ◽

Sputtering Pressure

ABSTRACTThe magnetic and recording characteristics of Co-based thin film media are strongly influenced by microstructure. The media microstructural characteristics, in turn, depend on sputtering conditions of underlayers and magnetic layers. The role of Cr underlayer thickness and sputtering pressure have been reported previously. The present work examines the growth morphology and recording properties of a CoPtCr alloy on Cr underlayers where the deposition conditions such as sputtering pressure and rf bias were independently varied for the Cr underlayer and the magnetic layer. We find that the growth morphology of the magnetic layer is governed primarily by the deposition condition of the Cr underlayer. In particular, increased sputtering pressure for the Cr underlayer produces columnar morphology which induces isolation of the grains in the magnetic layer. This results in a significant reduction in the recording noise due to reduced intergrain exchange coupling. On the other hand, the application of ff bias during the deposition of the magnetic layer promotes more continuous magnetic grains, thereby increasing the recording noise. The observed trends in microstructure and recording noise can be understood qualitatively in terms of Thornton's microstructure diagram and the competition between micromorphological roughness and adatom mobility during the film growth.

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Multi-scale and spatially resolved hydrogen mapping in a Ni–Nb model alloy reveals the role of the δ phase in hydrogen embrittlement of alloy 718

Acta Materialia ◽

10.1016/j.actamat.2016.02.053 ◽

2016 ◽

Vol 109 ◽

pp. 69-81 ◽

Cited By ~ 57

Author(s):

Z. Tarzimoghadam ◽

M. Rohwerder ◽

S.V. Merzlikin ◽

A. Bashir ◽

L. Yedra ◽

...

Keyword(s):

Hydrogen Embrittlement ◽

Model Alloy ◽

Alloy 718 ◽

Multi Scale ◽

Spatially Resolved ◽

Δ Phase

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Friction/Wear Behaviors of Magnetron Sputtered TiB2-C Composite Films on Ti6Al4V Alloy Substrate

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.189-193.979 ◽

2011 ◽

Vol 189-193 ◽

pp. 979-982

Author(s):

Xiao Jing Xu ◽

Xin Lan Sheng ◽

Dan Chen ◽

Xi Ling Xin ◽

Kun Tian ◽

...

Keyword(s):

Room Temperature ◽

Composite Films ◽

Ti6al4v Alloy ◽

Wear Properties ◽

Microstructural Characteristics ◽

Carbon Doped ◽

Alloy Substrate ◽

Sic Films ◽

Ball On Disc

The microstructure and friction/wear properties of TiB2-C (carbon-doped TiB2) films in TiB2-C/SiC double layer films (SiC films as interlayer) deposited on Ti6Al4V alloy substrate using magnetron sputtering technique at room temperature were investigated. The results show that the TiB2-C films exhibited the microstructural characteristics with nano-scale particles (domains), and the doped-carbon presented in manner of sp3 C-C and sp2 C-C bonds i.e. DLC (diamond-like carbon). The interface between the substrate and the SiC films and the interface between the SiC films and the TiB2-C composite films both showed good adhesion, with obvious element diffusions. As sliding against Si3N4 (silicon nitride) balls (2 mm in radius) using ball-on-disc type wear tester at room temperature under Kokubo simulation body fluid (SBF) and 50g load, the TiB2 -C composite films exhibited the friction coefficient of about 0.14 and the specific wear rate of 10.710-6 mm3 m−1 N−1. It is believed that the superior friction properties of the TiB2-C films are due to the role of the doped-carbon.

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