Reaction‐Controlled Binder Burnout of Ceramic Multilayer Capacitors

Verweij, H.; Bruggink, W.H.M.

doi:10.1111/j.1151-2916.1990.tb06497.x

Cited by 27 publications

(14 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The strategy proposed here for developing binder burnout cycles can be compared with the process control strategy of monitoring weight loss within the furnace and then varying the temperature so that the rate of weight loss is kept below some prescribed value. 30,31 Both methods are based on a heuristic; in our case on the threshold pressure and for the other on the rate of weight loss. The latter method can also be used on samples of different length, as long the feedback rate of weight loss is from samples of the same dimension as the actual components being subjected to binder removal.…”

Section: (2) Modeling Of Pressure Buildupmentioning

confidence: 99%

Determination of Binder Decomposition Kinetics for Specifying Heating Parameters in Binder Burnout Cycles

Shende

Lombardo

2002

Journal of the American Ceramic Society

View full text Add to dashboard Cite

The decomposition kinetics of poly(vinyl butyral) binder from barium titanate multilayer ceramic capacitors with platinum metal electrodes were analyzed by thermogravimetric analysis as a function of the heating rate. The activation energy and pre-exponential factor for the decomposition kinetics were determined from two types of integral equations, from the Redhead method, and from the variation in heating rate method. The accuracy of the kinetic parameters determined from these methods was then evaluated for describing the observed rate of binder decomposition. Although the individual models yielded very different kinetic parameters, all were capable of describing the experimental data within ؎15% accuracy. The kinetic parameters were then used in a coupled transport and kinetic model for describing the buildup of pressure within the ceramic green body as a function of the heating cycle. A methodology based on calculus of variations was also developed to predict the minimum duration for the binder burnout cycle.

show abstract

Section: (2) Modeling Of Pressure Buildupmentioning

confidence: 99%

Determination of Binder Decomposition Kinetics for Specifying Heating Parameters in Binder Burnout Cycles

Shende

Lombardo

2002

Journal of the American Ceramic Society

View full text Add to dashboard Cite

show abstract

“…There is a growing awareness of the significance of binder burnout as an essential step in ceramic processing (Rice, 1990;Verweij and Bruggink, 1990;Lewis and Cima, 1990;Cima et al, 1989a;Shukla and Hill, 1989). In the binder burnout step, organic binders, which provide strength and plasticity to ceramic green bodies, are thermally removed before sintering.…”

Section: Introductionmentioning

confidence: 99%

“…The temperature distribution in a green body is related to the thermal properties of constitutent phases, the heat effects of pyrolysis, and the convective heat flow due to effluent gas. Although in certain cases the heat effect might be so large that it causes a self-propagating reaction (Verweij et al, 1990), the reaction rate and its accompanying heat generation rate are normally kept low to prevent the sudden generation of a large amount of gas. Similarly, since the gas flow rate is usually small, its convective contribution is also small.…”

Section: Introductionmentioning

confidence: 99%

Pressure buildup and internal stresses during binder burnout: Numerical analysis

Tsai¹

1991

AIChE Journal

View full text Add to dashboard Cite

“…Possible solutions include imposing external constraints as in hot pressing, and application of advanced control algorithms. Examples of the latter include measuring a property such as overall weight [4], released humidity, and external dimensions, and comparing that property with a set-point to obtain the optimum ambient conditions by feed-back control. For the most complex cases 3D multi-zone control of temperatures and atmospheres might be applied in combination of real-time finite element analysis of the actual process.…”

Section: D Ambient Controlmentioning

confidence: 99%

Ceramic processing for multi-material devices with complex geometry

Zhang

Verweij

2007

2007 IEEE Antennas and Propagation Society International Symposium

View full text Add to dashboard Cite

Recent antenna designs, as shown in figures 1 and 2, have a complex 3D distribution of different materials that must form a cohesive, and often highly asymmetric entity. The distinct materials in such designs have special dielectric and magnetic properties, and often low electromagnetic losses. This implies that the materials of choice are mainly oxides that are made by ceramic routes for practical reasons. Ceramic routes start from powders that are consolidated into a pre-designed, "green," shape, followed by thermal processing to realize the target micro-structure. Thermal processing can be described as a sequence of drying to remove volatile processing liquids, removal of binders and other additives, and finally sintering. Sintering is the process of gradual densification of particulate compacts in which individual particles merge into bigger grains while, simultaneously, the void space (porosity) between the particles disappears. The equivalent porosity of green compact is 30…80%, while the final porosity should be 0…5% for most RF materials. This makes that the linear dimensions of the sintered shape are 10…40% less than the initial dimensions of the green compact. Practical ceramic compacts exhibit unwanted deviations from ideal shrinkage behavior such as cracking, warping, delamination and bloating. It is an ongoing and major challenge in state-of-the-art ceramics to keep these deviations within acceptable limits.Thermal processing behavior of single phase compacts strongly depends on chemical composition and powder particle morphology. This has the result that attempts to make complex devices in one commensurate process require major innovations and efforts in process design, analysis and optimization. An addi-Layer 4 ε = 15 Layer 1 Layer 2 Layer 3 ε = 15 ε = 20 ε = 70 α-Al 2 O 3 /TiO 2 composite @ diff. ratios Layer 4 ε = 15 Layer 1 Layer 2 Layer 3 ε = 15 ε = 20 ε = 70 α-Al 2 O 3 /TiO 2 composite @ diff. ratios Figure 1: Mulitiple Textured Layers design with 4 6×6 cm layers. Layers 1…3 are built from an inhomogeneous distribution of 2×4 mm quasi-homogeneous blocks with 3 different ε's. 0.75mm 1.25mm 0.25mm Ø = 0.5mm 0.75mm 12.5º 50mm 10-40 units 50mm 1 st layer TiO 2 ceramic rods 2 nd layer of same TiO 2 ceramic rods, but rotated 12.5º 3 rd layer of CVG ferrite One cell MPA structure 0.75mm 1.25mm 0.25mm 0.75mm 1.25mm 0.25mm Ø = 0.5mm 0.75mm 12.5º Ø = 0.5mm 0.75mm 12.5º 50mm 10-40 units 50mm 50mm 10-40 units 50mm 1 st layer TiO 2 ceramic rods 2 nd layer of same TiO 2 ceramic rods, but rotated 12.5º 3 rd layer of CVG ferrite One cell MPA structureFigure 2: Magnetic Photonic Assembly (MPA) design [1] consisting of 10…40 cells with 5×5 cm in-plane dimensions. The cells are built of two layers of parallel TiO 2 ceramic rods and one layer ferrite (CVG).

show abstract

Reaction‐Controlled Binder Burnout of Ceramic Multilayer Capacitors

Cited by 27 publications

References 3 publications

Determination of Binder Decomposition Kinetics for Specifying Heating Parameters in Binder Burnout Cycles

Determination of Binder Decomposition Kinetics for Specifying Heating Parameters in Binder Burnout Cycles

Pressure buildup and internal stresses during binder burnout: Numerical analysis

Ceramic processing for multi-material devices with complex geometry

Contact Info

Product

Resources

About