Investigation of continuous deposition of AMA-type coatings onto strip and sheet by sputtering

Technical Report · Tue Dec 01 04:00:00 EST 1981

OSTI ID:5663350

Thornton, J A; Lamb, J L

In a previous program it was shown that Al/sub 2/O/sub 3/-Mo-Al/sub 2/O/sub 3/ coatings, with hemispherical absorptances (..cap alpha..H) of 0.90 to 0.95 and room temperature emittances of less than 0.10, and with promising thermal stability, could be deposited by magnetron sputtering. Coatings on Mo-coated glass and stainless steel substrates were stable in air to about 300/sup 0/C when the Al/sub 2/O/sub 3/ layers were deposited by reactive sputtering, and to about 550/sup 0/C when these layers were deposited by rf sputtering from an alumina target. The objective of the present program is to investigate the continuous deposition of such multilayer selective absorber coatings onto strip by planar magnetron sputtering. The work also involves investigating metal-layer materials, other than Mo, that might provide improved thermal stability in air. Cr, Mo, Ni, Ta, and a Pt/Al/sub 2/O/sub 3/ cermet have been examined for use as the intermediate metal layer. In each case the same metal was also used for the low emittance base layer. The substrates were glass and stainless steel plates. Good spectral selectivity, ..cap alpha..H of 0.90 to 0.95 and emittance at 20/sup 0/C of 0.10, has been achieved on glass substrates for all of the materials. The thermal stabilities of the coatings confirm the earlier work and underscore the importance of the Al/sub 2/O/sub 3/ layer. Coatings on glass substrates with rf sputtered Al/sub 2/O/sub 3/ layers were stable in air to 500 to 600/sup 0/C and in vacuum to at least 650 to 700/sup 0/C; they appear attractive for medium and high temperature collectors. The Mo and Ni-based coatings with reactive sputtering Al/sub 2/O/sub 3/ were stable during 1000 hr-long tests in air at 350/sup 0/C and show promise as low-cost coatings for low-temperature (< 250/sup 0/C) flat plate collector applications. Accordingly, Ni-based and Mo-based coatings are being investigated in the continuous deposition studies.

• Research Organization: TELIC Corp., Santa Monica, CA (USA)
• DOE Contract Number: AC04-80AL13116
• OSTI ID: 5663350
• Report Number(s): DOE/AL/13116-T1; TELIC-81-3; ON: DE82004266
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
141000* -- Solar Collectors &amp; Concentrators
ABSORPTIVITY
ALLOYS
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
CERMETS
CHALCOGENIDES
CHROMIUM
CHROMIUM ALLOYS
COMPOSITE MATERIALS
CORROSION RESISTANT ALLOYS
ELECTRON TUBES
ELECTRONIC EQUIPMENT
ELEMENTS
EMISSIVITY
EQUIPMENT
FLAT PLATE COLLECTORS
GLASS
IRON ALLOYS
IRON BASE ALLOYS
LAYERS
MAGNETRONS
MATERIALS
METALS
MICROWAVE EQUIPMENT
MICROWAVE TUBES
MOLYBDENUM
NICKEL
OPTICAL PROPERTIES
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
PLATINUM
PLATINUM METALS
REFRACTORY METALS
SOLAR COLLECTORS
SOLAR EQUIPMENT
SPECTRALLY SELECTIVE SURFACES
SPUTTERING
STABILITY
STAINLESS STEELS
STEELS
SUBSTRATES
SURFACE PROPERTIES
SURFACES
TANTALUM
TEMPERATURE EFFECTS
TRANSITION ELEMENTS