The RF Converters market has recently significantly evolved: new programs show a great step in terms of linearity performances which induce higher heat dissipation. Requests for proposal (RFP) and programs have convinced THALES ALENIA SPACE to analyze the feasibility of "Thermal Enhancement".
The heat conductivity of AlSi material is 7 times higher than thermal conductivity of the Kovar. Our macro-hybrids are today manufactured using Kovar packages. The AlSi mass density is low and AlSi is machinable.
These considerations and recent requests from satellite operators pushed THALES ALENIA SPACE to evaluate this material to propose competitive solution at equipment level.
Preliminary tests on samples. These tests were performed on these tests vehicles types:
Demonstrators Definition: Following these samples results, 2 types of representative demonstrators are defined to perform complete evaluation versus environmental conditions.
Version 1: Package (bottom and walls) in AlSi material, Fe Ni ring and kovar RF feed-through AuSn soldered.
Version 2: Bottom of package in AlSi material, kovar walls, kovar RF feed-through and kovar fixation feet AuSn soldered.
To present a product with higher thermal performances.
THALES ALENIA SPACE proposes here to design critical elements and models of RF Macro-hybrids packages using AlSi Material.
The brittleness and the high cost are the main drawbacks of AlSi. It is therefore mandatory to secure all the machining and assembly processes versus the space environmental conditions in terms of thermal and mechanical constraints.
The activities are organized in two phases:
Define the design of demonstrators using:
Fully Complete qualification phase on the Phase 1 best evaluated solution.
The results of the different tests performed within the framework of this phase 1, in particular on both demonstrator versions whose designs were defined thanks to the tests of the phase of evaluation, concluded: