CERAMATEC'S VERTICALLY INTEGRATED TAPE CASTING PROCESS FLOW
One of Ceramatec's core strengths is the ability to formulate slip for successful tape casting, based on powder characteristics. Through in-house laboratory measurement of key powder attributes, Ceramatec employs the best-fit combination of solvents, binders and slip processing techniques to yield a castable material.
Three manufacturing-scale casters and one prototype-scale caster are employed at Ceramatec (see Table). Machine selection is based on the casting thickness and width (up to 18 inches), desired output volume, and specific needs of the binder system employed. To assure product performance and high levels of quality control, all casting is performed in a Class 10,000 clean room.
|Tape Caster||Green Casting Thickness Capabilities||Drying Oven Length||Notes|
|ELIT (HYMC Fabricated)||8 mils – 47 mils
(203 μm – 1,219 μm)
|50 ft||Atmospheric (air-flow) Control
Atmospheric Temperature Control
(203 µm – 1,219 µm)
|2 mils to 10 mils
(51 µm – 254 µm)
|40 ft.||Tape Carrier Temperature Control
Atmospheric Temperature Control
|2 mils to 25 mils
(51 μm – 635 μm)
|BUGG-O||3 mils to 40 mils
(76 μm – 1,016 μm)
|N/A||Used for slip property development and formulation optimization|
The output of the casting procedure is typically a roll or sheet of tape. Essentially a ceramic-filled polymer, the tape can cut or punched to the desired geometry. Typical methods employed to perform this operation include appropriately tooled mechanical punch presses, lasers, or specialized CNC punches/cutters. Ceramatec has three presses and the ability to design tools for the mechanical punching of tape.
Ceramatec employs three CO2 LASERS for precision location green featuring. The LASER allows for the cutting of channels and holes down to 0.006” wide, with tolerance capability of 0.001”. The use of these features in laminated structures enable technologies such as three dimensional electrical traces and cross-flow structures for active cooling applications.
One of the benefits of tape cast systems utilizing thermoplastic binders is the ability to stack layers of tape in registry and laminate them together to form a green structure. This lamination process is performed under uniform time/temperature/pressure conditions to assure complete and intimate lamination, while at the same time avoiding distortion of the designed structure. Ceramatec employs 10, 75 and 200 Ton lamination presses with heated plattens to perform this critical operation.
Ceramatec has several hydraulic presses of varying capabilities (2 Tons, 6 Tons, and 40 Tons) for the compaction and forming of almost any ceramic powder into green bodies of a desired configuration based upon program and customer requirements. Coupled with a cold isostatic press, which also adds tubular membranes into the repertoire of green part forming capabilities, Ceramatec can provide almost any green-forming solution.
As with all other green ceramic structures, the product must ultimately be fired. Ceramatec has extensive thermal processing capabilities that are specifically designed for the sintering of these unique, high-binder systems. They have the capability to fire in both air and controlled atmospheres, with temperature capabilities up to 2200 C. The development of specific firing profiles is dictated by the high volume percentage binder loading in tape systems. Given their 40-year history of working with these systems, Ceramatec excels in this area.
Ceramatec has the capability to tape cast most ceramic powders. Utilizing the vertically-integrated process detailed above, Ceramatec has successfully cast the following materials: ZrO2, Al2O3, SiO2, Mullite, CaO, MgO, CeO2, BaCeO3 AlN, YSZ, NiO / YSZ, ScSZ, YYbSZ, SiC, AlSiC, Ti3SiC2 Si3N4, LSCo, LSCF, LCM, LSGM, LaFeO3, SiAlON, Rare Earth Oxides, NaSICON, LiSICON, Stainless Steel, Al metal, Graphite, Cellulose.