Short Repetitive Pulses of 50-75 kV Applied to Plasma Immersion Implantation of Aerospace Materials

Summary form only given. High-energy plasma immersion ion implantation (PHI) in the range of 50-100kV is an interesting alternative of surface modification technique to more commonly investigated beam processing of materials in such energies. Although PHI process working at high voltages (50 -100kV) had been demonstrated previously as described elsewhere, the operation at this range has proved to be difficult due to the expensive hard-tube modulators required and hence most of PHI operation relies on pulser systems below 50 kV, typically. PHI is also an industrially method of ion implantation because it is a three-dimensional process. We have developed a 50-100 kV pulser system based on a stacked Blumlein technique (a much cheaper and simpler configuration) and applied it to our PHI process" with less than 50 kV. In the present paper, we will discuss PHI results obtained for operation range between 50 and 75 kV, which has been made possible due to vacuum system improvement and use of a higher voltage feedthrough, more recently. Higher implantation energies mean deeper ion penetration and hence much more reliable treatment and, in certain materials, they mean penetration through natural oxide layers, therefore avoiding oxide removal. In our previous results with < 50 kV. we observed good anti-corrosion properties for aluminum alloys, improved tribological and mechanical properties of Ti6A14V and DLC formation on polymer surfaces, after nitrogen PHI. Surface improvements in light materials commonly used in aerospace applications are being looked for in recent years to improve further the performance of aerospace systems. Prom the point of view of PHI process development itself, the studied range of 50-75 kV with low duty cycle is an interesting method to explore the surface treatment of materials with low melting point since polymers or Al alloys cannot be exposed to high temperatures such as steels or Ti alloys.