Mechanisms of nanostructure and metastable phase formations in the surface melted layers of a HCPEB-treated D2 steel

Pulsed intense ion beams have been developed for applications including surface modification and alloying, and thin-film and nanopowder synthesis. Rapid thermal processing with ions is quite promising for large-scale commercial use, due to the high specific ion energy deposition (joules per cubic centimeter) without reflection, and to the relative efficiency and low cost of the pulsed power ion-beam drivers compared to other high-kinetic energy alternatives. We discuss in this paper the basis for the use of ions in materials processing and the methods of beam formation and impingement on material to be treated, and give examples of recent and ongoing work in materials processing.

Materials modification using intense ion beams

The state of the art in the modification of iron, steel, and titanium alloys and some metal multilayers by medium intensity (106–109 W cm−2) pulsed electron and ion beams is summarized, including the contribution from the authors. Many of the processes that determine the defect structure and its properties are described and such problems as the formation of elastoplastic and shock waves, mixing of multilayers, thin film deposition, and nanophase powder synthesis are discussed. The high potential of particle beam technology — in particular, for improving the operating characteristics of materials — has been demonstrated amply by research centers worldwide.

Metal modification by high-power pulsed particle beams

The review is concerned with the current status of research on the use of plasma jets for the modification of surface properties of metalware, as well as of investigations of doping and mass transfer of elements. The effect of thermal plasma parameters on the efficiency of surface processing of metal materials is discussed. The structure and properties of protective coatings produced by exposure to pulsed plasmas are analyzed. A new direction for the production of combined coatings is considered. Their structure and properties were studied by the example of Fe, Cu, steels, and alloys, including titanium alloys; the modification process was shown to be controllable by the action of pulsed plasma jets. The physical factors that affect the modification process and the coating deposition, and their effect on the structure and properties of metallic, ceramic – metal, and ceramic coatings were analyzed.

Modification of material properties and coating deposition using plasma jets

Application of high intensity pulsed ion and plasma beams in modification of materials

A 300 keV, 30 kA, 1 μs intense beam ofcarbon, oxygen, and hydrogen ions is used for the surface treatment of AISI-4620 steel coupons, a common material used in automotive gear applications. The beam is extracted from a magnetically-insulated vacuum diode and deposited into the top 1 μm of the target surface. The beam-solid interaction causes a rapid melt and resolidification with heating and cooling rates of up to 1010 K/s. Treated surfaces are smoothed over 1 μm-scale lengths, but are accompanied by 1 μm-diameter craters and larger-scale roughening over ≥ 10 μm, depending on beam fluence and number of pulses. Treated surfaces are up to 1.8 × harder with no discernible change in modulus over depths of 1 μm or more. Qualitative improvements in the wear morphology of treated surfaces are reported.

/pdf/surface-modification-of-aisi-4620-steel-with-intense-pulsed-ad7gpx96r3.pdf

Surface modification of AISI-4620 steel with intense pulsed ion beams

A 300-keV, 30-kA, 1-{micro}s intense beam of carbon, oxygen, and hydrogen ions is used for the surface treatment of AISI-4620 steel coupons, a common material used in automotive gear applications. The beam is extracted from a magnetically-insulated vacuum diode and deposited into the top 1 {micro}m of the target surface. The beam-solid interaction causes a rapid melt and resolidification with heating and cooling rates of up to 10{sup 10} K/sec. Treated surfaces are smoothed over 1-{micro}m scale-lengths, but are accompanied by 1-{micro}m diameter craters and larger-scale roughening over >=10 {micro}m, depending on beam fluence and number of pulses. Treated surfaces are up to 1.8 x harder with no discernible change in modulus over depths of 1 {micro}m or more Qualitative improvements in the wear morphology of treated surfaces are reported.

/pdf/surface-modification-of-aisi-4620-steel-with-intense-pulsed-5ejqhub0pn.pdf

R.D. Reiswig

Papers

Surface modification of AISI-4620 steel with intense pulsed ion beams

Surface Modification of AISI-4620 Steel With Intense Pulsed Ion Beams