Non-Vacuum Electron Beam Welding

Original objectives of CRADA number BNL-01-03 between BNL and Acceleron, Inc., were to further develop the Plasma Window concept (a BNL invention covered by US Patent number 5,578,831), mate the Plasma Window to an existing electron beam welder to perform in-air electron beam welding, and mount the novel nonvacuum electron beam welder on a robot arm. Except for the last objective, all other goals were met or exceeded. Plasma Window design and operation was enhanced during the project, and it was successfully mated to a conventional4 kW electron beam welder. Unprecedented high quality non-vacuum electron beam . welding was demonstrated. Additionally, a new invention the Plasma Shield (US Patent number 7,075,030) that chemically and thermally shields a target object was set forth. Great interest in the new technology was shown by a number of industries and three arcs were sold for experimental use. However, the welding industry requested demonstration of high speed welding, which requires 100 kW electron beam welders. The cost of such a welder involved the need for additional funding. Therefore, some of the effort was directed towards Plasma Shield development. Although relatively a small portion of the R&D effort was spent on the Plasma Shield, some very encouraging results were obtained. Inair Plasma Shield was demonstrated. With only a partial shield, enhanced vacuum separation and cleaner welds were realized. And, electron beam propagation in atmosphere improved by a factor of about 3. Benefits to industry are the introduction of two new technologies. BNL benefited from licensing fee cash, from partial payment for employee salary, and from a new patent In addition to financial benefits, a new technology for physics studies was developed. Recommendations for future work are to develop an under-water plasma shield, perform welding with high-power electron beam:s, carry out other plasma shielded electron beam and laser processes. Potential benefits from further R&D are that various processes involving electron ion and laser beams that have now restrictions can, with the Plasma Shield be performed in practically any environment. For example, electron beam and laser welding can be performed under water, as well as, in situ repair of ship and nuclear reactor components. The plasma shield results in both thermal (since the plasma is hotter than the environment) and chemical shielding. The latter feature brings about in-vacuum process purity out of vacuum, and the thermal shielding aspect results in higher production rates

Plasma Dynamics

Contains reports on two research projects.U. S. Energy Research and Development Administration (Contract E(l1-1)-3070)National Science Foundation (Grant ENG75-06242

Plasmas and Controlled Nuclear Fusion

Contains reports on four research project.U. S. Atomic Energy Commission (Contract AT(11-1)-3070

Plasma Dynamics

Contains research objectives and summary of research on eighteen research projects split into seven sections and reports on four research projects.U.S. Atomic Energy Commission (Contract AT(l1-1)-3070)National Science Foundation (Grant GK-37979X1

Plasma Dynamics

Contains reports on seventeen research projects split into two sections.National Science Foundation (Grant ENG77-00340)U. S. Energy Research and Development Administration (Contract E(11-1)-2766)U. S. Energy Research and Development Administration (Contract EY-76-S-02-2766)U. S. Air Force - Office of Scientific Research (Grant AFOSR-77-3143)U. S. Department of Energy (Grant EG-77-G-01-4107

Plasma Dynamics

Contains research objectives and summary of research on nineteen research projects split into five sections.National Science Foundation (Grant ENG75-06242-A01)U.S. Energy Research and Development Administration (Contract E(11-1)-2766)U.S. Air Force - Office of Scientific Research (Grant AFOSR-77-3143)U.S. Energy Research and Development Administration (Contract EY-76-C2-02-3070.*000

Plasma Dynamics

Contains research objectives and summary of research on twenty-one projects split into three sections, with four sub-sections in the second section and reports on twelve research projects.National Science Foundation (Grant ENG75-06242)U.S. Energy Research and Development Administration (Contract E(11-1)-2766)U.S. Energy Research and Development Agency (Contract E(11-1)-3070)U.S. Energy Research and Development Administration (Contract E(11-1)-3070)Research Laboratory of Electronics, M.I.T. Industrial Fellowshi

Issues Concerning High Current Lower Energy Electron Beams Required for Ion Cooling between EBIS LINAC and Booster Issues Concerning High Current Low Energy Electron Beams Required for Ion Cooling between EBIS LINAC and Booster

Some issues, regarding a low energy high current electron beam that will be needed for electron beam cooling to reduce momentum of gold ions exiting the EBIS LINAC before injection into the booster, are exmuined. Options for propagating such an electron beam, as wen as the effect of neutralizing background plasma on electron and ion beam parameters are calculated. Computations and some experimental data indicate that none of these issues is a show stopper

INVESTIGATION OF A PLASMA MODE IN EBTS

Abstract: A plasma related mode has been identitled when EBTS operated with long trap length. The mode frequency scaling showed monotonic increased with confinement time. Initial scaling qualitatively suggested the mode to an electron beam chiven ion cyclotron instability. However, a more quantitative evaluation is indicative of a drift mode. Nevertheless, the possibility of a structure mode, though unlikely, can not be completely excluded. The process of proper instability identification and stabilization is described