Welding of 304 stainless steel and glass using high-repetition-frequency femtosecond laser

AbstractIn this work we reported low and high repetition frequency femtosecond laser-induced modifications of tungsten-based thin film. The tungsten-titanium (WTi) thin film, thickness of 190 nm, was deposited by sputtering on single crystal Si (100) wafer. Irradiations were performed in air by linearly polarized and focused femtosecond laser beams with following parameters: (1) pulse duration 160 fs, wavelength 800 nm, laser repetition frequency (LRF) 75 MHz — high LRF, and (2) duration 40 fs, wavelength 800 nm, LRF of 1 kHz — low LRF. The results of femtosecond lasers processing of the WTi thin film revealed laser induced periodical surface structures (LIPSS) in the case of low LRF regime. LIPSSs were formed with different periodicity and different orientation to the laser polarization at the surface: micro-scale LIPSSs with orientation perpendicular to the laser polarization and nano-scale LIPSSs parallel and perpendicular to the laser polarization. After processing of the WTi/Si system in high LRF regime ablation and nano-particles formation were registered.

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Comparison of Recovery and Recrystallization in Stainless Steel Following Plane-Wave Shock Loading and Explosive Forming

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069132 ◽

1970 ◽

Vol 28 ◽

pp. 428-429 ◽

Cited By ~ 2

Author(s):

J. A. Korbonski ◽

L. E. Murr

Keyword(s):

Stainless Steel ◽

Shock Loading ◽

Pressure Pulse ◽

Shock Pressure ◽

304 Stainless Steel ◽

Strain Rates ◽

Two Dimensional ◽

Aisi 304 Stainless Steel ◽

Aisi 304 ◽

Explosive Forming

Comparison of recovery rates in materials deformed by a unidimensional and two dimensional strains at strain rates in excess of 104 sec.−1 was performed on AISI 304 Stainless Steel. A number of unidirectionally strained foil samples were deformed by shock waves at graduated pressure levels as described by Murr and Grace. The two dimensionally strained foil samples were obtained from radially expanded cylinders by a constant shock pressure pulse and graduated strain as described by Foitz, et al.

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Pyrolytic carbon filaments and associated catalytic particles formed in steel tubes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100113196 ◽

1984 ◽

Vol 42 ◽

pp. 662-663

Author(s):

Y. L. Chen ◽

J. R. Bradley

Keyword(s):

Stainless Steel ◽

Carbon Steel ◽

Catalyst Particle ◽

Pyrolytic Carbon ◽

Plain Carbon Steel ◽

304 Stainless Steel ◽

Hydrocarbon Gases ◽

Steel Tubes ◽

Filamentous Carbon ◽

Carbon Filaments

Considerable effort has been directed toward an improved understanding of the production of the strong and stiff ∼ 1-20 μm diameter pyrolytic carbon fibers of the type reported by Koyama and, more recently, by Tibbetts. These macroscopic fibers are produced when pyrolytic carbon filaments (∼ 0.1 μm or less in diameter) are thickened by deposition of carbon during thermal decomposition of hydrocarbon gases. Each such precursor filament normally lengthens in association with an attached catalyst particle. The subject of filamentous carbon formation and much of the work on characterization of the catalyst particles have been reviewed thoroughly by Baker and Harris. However, identification of the catalyst particles remains a problem of continuing interest. The purpose of this work was to characterize the microstructure of the pyrolytic carbon filaments and the catalyst particles formed inside stainless steel and plain carbon steel tubes. For the present study, natural gas (∼; 97 % methane) was passed through type 304 stainless steel and SAE 1020 plain carbon steel tubes at 1240°K.

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