INSITU METAL MATRIX NANOCOMPOSITE SYNTHESIS BY ADDITIVE MANUFACTURING ROUTE

Abstract

A unique and novel additive manufacturing route has been proposed to form a thermally stable in-situ metal matrix nano composite by interfacing reactive plasma in the selective laser melting process chamber. The proposed route gives very high compositional freedom, i.e, nitrides, carbides, oxides, suicides and other ceramics with different stoichiometries can be reinforced in nanoscale in any metallic matrix. Components with such a nanocomposite structure dispiay superior high temperature structural properties.

Claims

1. Additive, manufacturing synthesis method to form a component comprising a metal matrix nanocomposite, the method comprising the steps of: Reactive plasma ignition in the chamber preferentially on a Me powder bed, where the Me powder is a metal comprising powder and simultaneously applying an electrostatic potential of several 100 eV in the melt zone via the build platform Laser raste ing on the powder bed to cause molten pool formation very locally Electrostatically driving reactive gas ions X+ as for example (N+, O+, Si+, B+, and/or C+) into the molten pool with an energy of several 100 eV. Causing chemical interaction between the molten feed stock and reactive gas ions to form ceramic compounds such as carbides, nitrides, oxides, and/or silicides insitu for example: by the following reaction path way: {Me(I)+X+(g).fwdarw.MeX(s)}, Solidifying and thereby forming the metal matrix composite with nanoscale dispersion,

2. Method according to claim 1, characterized in that the laser power and or rastering speed and/or bias voltage is tuned to influence plasma reactivity and/or hydrodynamic forces and/or fluid recirculation pattern of the molten feedstock to cause nitride precipitates break down preferentially to nanoscale before the liquid pool solidifies.

3. Method according to one of the claims 1 and 2, characterized in thatreactive gas ions X+ are N+ ions.

4. Method accordingne of the claims 1 to 3, characterized that Me is Ti and/dr Al or a mixture thereof.

Description

[0020] FIG. 1: Schematic illustration of (a) layer spreading and laser melting, (b) forming desired shape by selective laser melting process

[0021] FIG. 2: Structural differences of the additive manufactured co with tide a) state of the art and b) the proposed synthesis route

[0022] FIG. 3: Pictorial representation of insitu metal matrix nanocomposite formation in the proposed synthesis route. Numbers in the picture represents sequential process steps explained in the text.