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The influence of the rapidly changing aperture field on the stainless-steel beam tube is examined along with the eddy-current losses. The studies have shown that the saturation pattern in and around the bridge has changed at the start of the ramping, thus resulting in a changing field quality.

The design and testing of superconducting fault current limiter (SFCL) wound with stainless steel-stabilized coated conductor are discussed. Results suggest the effective amelioration of the compactness in the fabrication of SFCL rated on larger capacity.

Various limitation experiments with coated conductors in function of the temperature based on a processing route with a stainless steel shunt and a gold shunt are explained. The temperature sensors used are found to show great time response and sensitivity.

The analysis describes a new technique for the fabrication of long-length coated conductors based on stainless steel tapes with better properties and chemical stability. These conductors are shown to exhibit excellent homogeneity and performance.

Several studies are conducted to enhance the brass and stainless steel reinforcement of the high temperature superconducting (HTS) wires and tapes. These tapes can be used for various applications by altering their applications according to the needs.

A dynamic electronic speckle pattern interferometry method is applied to investigate thermal expansion of a joint material (ceramic-stainless steel) as a practical industrial object. The speckle interference signal is considered in the temporal domain and the phase is analyzed by the Hilbert transform method. Errors caused by the bias and modulation variations over the phase values are first examined by numerical simulation. Two experiments are performed with in-plane and out-of-plane sensitive systems to study the 3D deformation field thoroughly. The deformation field showed clearly the difference between the thermal expansions of the stainless steel and ceramic. It was also revealed that the boundary of materials and its vicinity suffer very large thermal strain due to the significantly large difference in the linear coefficient of thermal expansions. OCIS codes: 120.6160, 120.5050, 100.2650.

A high-voltage pulsed power supply of 100 kV/200 A with output short pulses of the order of 1 [micro]s (based on stacked coaxial Blumlein technology) was developed for use in surface treatment of materials by plasma implantation. The plasma implantation process requires pulse repetition and the authors' device is capable of operating at a frequency range of 10-150 Hz, depending on the level of the output voltage. Herein, the authors show that nitrogen-ion species were implanted into stainless steel surfaces (SS304) at high energies (> 30 keV) by using this pulser, inducing [alpha] phase as demonstrated by X-ray diffraction diagnostic. Moreover, microhardness tests of these treated samples have shown an improvement of about 13.0% for the surface hardness factor. Index Terms--Blumlein pulser, hardness factor, nitrogen, plasma implantation, stainless steel (SS), surface treatment.

An investigation of the HV vacuum breakdown between polished, powder coated, and e-beam treated 304L and 316L stainless steel electrodes is described. Tests were performed with 160 ns, 1-cos([omega]t), and 260 ns flat-top voltage pulses of up to 500 kV. The high voltage hold-off for the 160 ns pulse was ~ 130 kV/mm for 2 mm gaps for 80mm diameter polished stainless steel electrodes, and 15% lower for 120-mm polished and e-beam treated electrodes. The longer 260 ns pulse gave 15% lower hold-off for 80mm electrodes. These electrodes showed voltage hold-off that scaled as the square root of the gap between 0.5 and 7 mm. This total voltage effect has been interpreted in the past as due to accelerated particles. We analyze our data in terms of this mechanism and show that only nanoparticles of molecular size could be responsible. We also discuss how ions or background gas could affect the breakdown thresholds but existing models do not predict square root dependence. We test how extremely fine powers affect hold-off and show that contaminated surfaces have relatively constant reduced breakdown E-fields that intersect the clean-electrode voltage-dependent breakdown at critical gaps defined by the type and quantity of contamination. The hold-off was ~ 55 and 65 kV/mm with copper powder on the cathode and anode for 2 to 6.5 mm gaps, respectively, and ~ 95 and 75 kV/mm for talc powder on the cathode and anode for gaps < 3.5 and 6.5 mm. Optical diagnostics show no difference in the light emission from clean and contaminated electrode breakdown arcs. Index Terms--Electrical insulation in vacuum, electrical breakdown in vacuum, vacuum discharge.

Several experiments are conducted to explain the hydrogen-induced crack initiation taking place in the different hydrogen-charged metastable austenitic stainless steels during deformation. The initiation and the propagation of the hydrogen-induced crack are also analyzed.

Several studies are conducted to explain the scaling behavior and the magnetic properties exhibited by the different loops present in the austenitic stainless steel. The results demonstrate the presence of a strong scaling relationship between the hysteresis loss and the remanence.

Various processes involved in laser drilling of thin stainless steel sheet in air and underwater are discussed. While the recoil pressure of the vapor and plasma has played a major role in laser drilling in air, the radial gradient of recoil pressure of evaporation, the Marangoni force induced by the surface tension gradient in melt pool and the cavitation effect of bubble collapse are responsible for the material removal in underwater drilling process.

The influence of sputtering parameters on the structural, mechanical, and electrical properties of nanoscale twinned 330 stainless steel thin films is explored. The increase in the room temperature electrical resistivity of the films, compared to bulk 330 stainless steel is found to be small, indicating that nanoscale twinned structures may provide the best combination of high mechanical strengths and high electrical conductivity.

The evolution of residual stresses as a function of bilayer period from 10nm to 1micrometer in sputter-deposited Cu/330 stainless-steel (SS) multilayered films is evaluated by the substrate curvature technique.

Hybrid plasma treatment combining high- and low- pressure ion nitriding is tested. The test results show that the two-cycle nitriding process, combining high-pressure and high-temperature stage followed by lower-pressure nitriding with a mixture of nitrogen and hydrogen showed good results, when applied to the AISI 304.

The mechanism involved in the nitriding process of stainless steel by ion implantation is discussed. Studies found that at relatively low ion energies and oxygen partial pressures, both the diffusion zone and nitrated layer thickness are controlled by the ion current density.