New nickel plated metal mirrors utilizing meltspun aluminium silicon alloy

High performance metal mirrors require a polishable surface layer to achieve the demands for the UV/VIS wavelengths. The amorphous electroless nickel (NiP) offers the possibility for the manufacturing of mirrors with exceilent figure and roughness [1]. However, the mirror substrate material particularly aluminium 6061 has a signiliicant mismateh in the coefficient of thermal expansion (CTE). Due to temperature changes, the bimetailic effcct introduces figure distortions. The ncw idea is tu match the CTE by using a meitspun aluminium alloy with a high silicon contents (\'12 40 %) as mirror substrate [2]. Besides the matching of the CTE, the specific stiffness shows a considerable increase compared to A1606 1.