Sagger

Abstract

A sagger having a body with a base and one or more sidewalls, the base and the one or more sidewalls having a thickness of about 13 mm or less and comprising about 50% by weight or less Al2O3 based on the total weight of the sagger, and a method for making the sagger.

Description

[Technical Field]

[0001] SUGGERS AND METHODS FOR MANUFACTURING SAGERS FIELD OF THE DISCLOSURE The present disclosure relates to saggers and methods for manufacturing saggers. [Background technology]

[0002] A sagger is a box-like item of kiln furniture that can be used to transport and / or protect powders. Saggers have traditionally been used in the baking or firing process of powders, such as catalyst powders and / or battery electrode material powders that can be used in modern electric vehicles. Saggers are often manufactured using a process that involves pressing ceramic powder into a mold to produce a green body or preform. As the demand for such powders increases, so does the demand for improved methods and equipment used to produce them. One particular need is for improved saggers that are stronger and / or lighter and may have chemical resistance to hot powders. Summary of the Invention

[0003] According to the present invention there is provided a sagger and a method as defined in any one of the accompanying claims. In one embodiment, the present invention provides a sagger having a body with a base and one or more side walls, the thickness of the bottom and the one or more side walls is about 13 mm or less, e.g., about 12 mm or less, or about 11 mm or less, or about 10 mm or less, or about 8 mm or less; the sagger comprises about 50 wt. % or less Al2O3, preferably about 45 wt. % or less Al2O3, based on its total mass; Approximately 1.6g / cm 3 ~About 3.0g / cm 3 , for example, about 1.6 g / cm 3 ~Approx. 2.3g / cm 3 and / or Approximately 1.5×10 -6 K -1 ~Approx. 5.0×10 -6 K -1, for example, about 2.0 x 10 -6 K -1 ~Approx. 4.0×10 -6 K -1 and / or and / or a modulus of rupture of about 15 MPa or more, e.g., about 20 MPa or more, or about 23 MPa or more; and / or The sagger has a modulus of rupture to thickness ratio of about 1.5 MPa / mm or more, for example, about 1.7 MPa / mm or more, or about 2.0 MPa / mm or more, preferably in the range of 1.5 MPa / mm to 4.0 MPa / mm. A sagar is provided. The sagger of the present invention provides desirable structural characteristics that allow the sagger to be lightweight, which improves its handling and transportability. The sagger may contain, based on its total mass, about 20 to about 55% by mass of mullite, about 30 to about 45% by mass of cordierite, and about 0 to 25% by mass of spinel, preferably about 0 to about 5% by mass of spinel, or about 0 to about 4% by mass of spinel. The saggur may contain about 5% to about 30% by mass of amorphous phase relative to its total mass, for example, about 10% to about 20% by mass of amorphous phase relative to its total mass. The sager may have a water absorption rate of about 5% to about 20%, for example, about 8% to about 16%, based on its total mass.

[0004] Alternatively, the sagger may contain about 40% to about 60% by weight of SiO2 and about 30% to about 50% by weight of Al2O3, based on its total weight, and the sagger may contain about 2.0% or less by weight of Fe2O3, for example, about 0.1% to about 2.0% by weight of Fe2O3, about 1.0% or less by weight of TiO2, for example, about 0.05% to about 1.0% by weight of TiO2, about 1.0% or less by weight of CaO, for example, about 0.01% to about 1.0% by weight of MgO, about 2.0% or less by weight of K2O, for example, about 0.01% to about 2.0% by weight of Na2O, and / or about 0.5% or less by weight of Na2O, for example, about 0.01% to about 0.5% by weight of Na2O.

[0005] The sagger may be a sagger for retaining powder during firing, for example, for retaining battery electrode material powder, such as battery cathode material powder, for example, for retaining oxides, hydroxides, carbonates, sulfates, and / or phosphates of one or more of lithium, titanium, vanadium, chromium, manganese, iron, cobalt, tungsten, and / or nickel. Surprisingly, it has been found that making the sagger by pressure casting results in a stronger sagger (stronger, for example, in terms of the sagger's modulus of rupture). Surprisingly, it has been found that producing saggers by high pressure casting results in stronger saggers (sturdier, e.g., in terms of the sagger's modulus of rupture) than saggers produced by low pressure casting when the sagger thickness is low, i.e., 10 mm or less. And, a stronger sagger allows the thickness of the sagger body, including its base and / or walls, to be reduced, making it less easy to handle, transport, and cost-effective. Reducing the thickness of the base and / or walls of the sagger body can also lead to reduced raw material consumption, reduced amount of material recycled at the end of the sagger's life, reduced thermal inertia, and reduced thermal gradients. It also makes the sagger lighter, which is an advantage in shipping and makes it easier to transport. It has also been surprisingly found that pressure casting according to the present invention can produce saggers with low Al2O3 contents, which provide saggers that are at least as strong (e.g., in terms of the sagger's modulus of rupture) as saggers with higher Al2O3 contents, resulting in greater weight savings at lower manufacturing costs.

[0006] Also, a method for making a sagger for use in a kiln includes the steps of pressure casting a slip composition in a mold cavity at a pressure of about 200 kPa to about 4000 kPa to form a green sagger body; removing the green sagger body from the mold cavity; baking the green sagger body to produce a baked sagger body; A method is also provided, including: During pressure casting of the slip composition within the mold cavity, filtrate may be removed from the mold cavity via an outlet configured to prevent flow therethrough of solid components of the slip composition.

[0007] The slip composition may comprise one or more layered silicate minerals and water. The layered silicate minerals include calcined or uncalcined layered silicate minerals. The one or more layered silicate minerals may include kaolin, smectite, illite, chlorite, talc, vermiculite, palygorskite, sepiolite, aluminosilicate chamotte, and / or any combination thereof. Further, the slip composition may include alumina, e.g., calcined alumina, corundum, magnesium carbonate, e.g., magnesite, mullite, kyanite, spinel, and / or any combination thereof. For example, the slip composition may include kaolin, calcined kaolin, talc, calcined alumina, corundum, mullite, and / or calcined clay, and any combination thereof. The slip composition may also include a deflocculating agent and / or a binder, such as a polycarboxylic acid, a polysaccharide, and / or a lignosulfonate.

[0008] The slip composition may have a density of about 1500 g / L to about 3000 g / L, e.g., about 1800 g / L to about 2800 g / L, or about 2000 g / L to about 2100 g / L, or about 2550 g / L to about 2650 g / L, a thixotropy as measured by a Gallenkamp universal torsional viscometer of about 15° G to about 30° G, with a first viscosity (i.e., overswing) measured immediately after stirring and a second viscosity (i.e., overswing) measured 5 minutes after stirring, and / or a moisture content of about 10% to about 30% by weight, based on the total weight of the sagger. The sagger may have a bottom and one or more side walls.

[0009] The bottom and one or more side walls may each have a thickness of about 13 mm or less, e.g., about 12 mm or less, about 11 mm or less, or about 10 mm or less, and the sagger, i.e., the fired sagger body, may have a modulus of rupture of about 15 MPa or more, e.g., about 20 MPa or more, or about 23 MPa or more. The sagger may be for retaining powder during firing. For example, the sagger may be for retaining battery electrode material powder, such as battery cathode material powder. For example, the sagger may be for retaining oxides, hydroxides, carbonates, sulfates, and / or phosphates of one or more of lithium, titanium, vanadium, chromium, manganese, iron, cobalt, tungsten, and / or nickel. Those skilled in the art will appreciate that, unless mutually exclusive, features described in connection with any of the above embodiments can also be applied mutatis mutandis to the other embodiments. Furthermore, unless mutually exclusive, any feature described herein can be applied to any embodiment and / or can be used in combination with any other feature described herein. Embodiments will now be described, by way of example only, with reference to the drawings in which: [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a perspective view of a box-shaped sagger. [Figure 2] 2A and 2B are a cross-sectional view and a plan view, respectively, of the box-shaped sagger of FIG. 1. DETAILED DESCRIPTION OF THE INVENTION

[0011] Sagger A saggar, also called a sagger, is a container suitable for transporting and / or protecting heavy loads within a kiln or furnace, more specifically a box-like type ceramic container used in the baking and firing of powders, such as catalyst powders and / or battery electrode material powders that can be used in modern electric vehicles. A sagger typically includes (e.g., may be) a container for securing a weight. The sagger may also include a lid (e.g., a plate) for covering (e.g., closing) an opening in the container. A sagger (e.g., a container) typically comprises a body including (e.g., formed from or consisting of) a bottom and one or more side walls. The body is typically box-shaped. Thus, saggers are sometimes known as box saggers. It will also be appreciated that the bottom and one or more side walls may take on a variety of shapes depending on the design of the sagger. The base is typically flat or planar. The base may be polygonal in shape (e.g., rectangular or square). It will be appreciated that a (e.g., substantially) polygonal base does not necessarily have sharp vertices, but may instead have rounded vertices. Each of the one or more side walls may be (e.g., substantially) flat (i.e., planar). Preferably, the base may be substantially rectangular in shape, and the sagger may comprise four side walls, each a substantially flat panel joined at a corresponding edge to the substantially rectangular base.

[0012] The one or more side walls may extend generally vertically upward from the base (i.e., when the sagger is positioned such that its base is substantially horizontal in use). Thus, each of the one or more side walls may be positioned substantially perpendicular to the base, although one or more of the side walls may be angled slightly outward (i.e., away from the interior space enclosed by the sagger). For example, each of the one or more side walls may extend from the base at an angle of about 80° to about 100°, e.g., about 85° to about 95°, or about 87° to about 93°, or about 88° to about 92°. The thickness of the base and one or more sidewalls may be substantially uniform throughout the sagger, or may vary in thickness. For example, the thickness of the base and one or more sidewalls may vary by about 3 mm or less, or about 2 mm or less, or about 1 mm or less throughout the base and one or more sidewalls.

[0013] The bottom and one or more sidewalls (e.g., maximum thickness, e.g., thickness of the bottom at its maximum thickness point) may have a thickness of about 13 mm or less, e.g., about 12 mm or less, or about 11 mm or less, or about 10 mm or less. The bottom and one or more sidewalls (e.g., minimum thickness, e.g., thickness of the bottom at its minimum thickness point) may have a thickness of about 4 mm or more, e.g., about 5 mm or more, or about 6 mm or more, or about 8 mm or more. The bottom and one or more sidewalls (e.g., maximum thickness, minimum thickness, or average thickness which is the average of the maximum and minimum thicknesses) may have a thickness of about 4 mm to about 13 mm, e.g., about 4 mm to about 12 mm, or about 4 mm to about 10 mm, or about 8 mm to about 12 mm, or about 8 mm to about 10 mm. The base may have a length and a width. The length and width may be measured at right angles to each other. The length and width of the base may be the length and width of the sagger, i.e., the baked sagger body. Each sidewall may have a height. The height may be the linear distance between the bottom edge of the sidewall where it meets the base and the top edge of the sidewall. The height may be measured along a line perpendicular to the bottom edge of the sidewall (where it meets the base). The height of the sidewalls may be substantially uniform, or the height of the sidewalls may vary depending on the profile of the sidewalls.

[0014] Each sidewall (e.g., at its minimum height, e.g., at the point where the height of the sidewall is smallest in embodiments where the height is not uniform) may have a height of about 50 mm or more, e.g., about 60 mm or more, or about 70 mm or more, or about 80 mm or more, or about 90 mm or more, or about 100 mm or more. Each sidewall (e.g., at its maximum height, e.g., at the point where the height of the sidewall is largest in embodiments where the height is not uniform) may have a height of about 200 mm or less, e.g., about 190 mm or less, or about 180 mm or less, or about 170 mm or less, or about 160 mm or less, or about 160 mm or less, or about 150 mm or less, or about 140 mm or less, or about 130 mm or less, or about 120 mm or less. The sagger, i.e., the baked sagger body, when unfilled may have a mass of about 2 kg or more, e.g., about 3 kg or more. The body may have a mass of about 4 kg or less when unfilled. The body may have a mass of about 2 kg to 4 kg when unfilled, e.g., about 3 kg to about 4 kg.

[0015] An example of a box sagger 1 is shown in FIG. 1. The sagger 1 has a box-shaped baked sagger body 2. The body 2 has a bottom 3 and four side walls 4A, 4B, 4C, and 4D. The four side walls 4A, 4B, 4C, and 4D are bordered by rounded corners 5A, 5B, 5C, and 5D. The outer surfaces of the side walls 4A, 4B, 4C, and 4D are raised near the rounded corners 5A, 5B, 5C, and 5D, for example, as indicated at 6.

[0016] Figure 2 shows the sagger 1 in (a) cross section and (b) plan view. The length of the base is denoted by L. The width of the base is denoted by W. The height of the sidewall is denoted by H. The thickness of the base is denoted by T.B The thickness of the side wall is T S The interior angle between the side wall and the bottom is represented by α. The exterior angle between the side wall and the bottom is represented by β.

[0017] The sagger may be a sagger for retaining powder during firing. The powder may be a battery electrode material powder, such as a battery cathode material powder. For example, the sagger may be for retaining one or more metal oxides, hydroxides, carbonates, sulfates, and / or phosphates. For example, the sagger may be for retaining one or more metal oxides, hydroxides, carbonates, sulfates, and / or phosphates of lithium, titanium, vanadium, chromium, manganese, iron, cobalt, tungsten, and / or nickel. Therefore, the sagger may be formed of a material that is not easily damaged when in contact with the powder at high temperatures.

[0018] Manufacturing method A method of making a sagger includes pressure casting a slip composition in a mold cavity to form a green sagger body, removing the green sagger body from the mold cavity, and firing the green sagger body to produce a fired sagger body. Pressure casting a part can be understood to include applying pressure (i.e., pressing) to a slip composition within a mold cavity during the molding process to form a green part body. Pressure casting can therefore be contrasted with non-pressure slip casting. Because pressure casting involves forming a green part body from a slip composition (i.e., a liquid slurry), pressure casting can also be contrasted with methods in which a green part body is formed by pressing dry ceramic powder within a mold cavity.

[0019] pressure casting The method may include pressure casting the slip composition into a mold cavity at a pressure of about 200 kPa or more, e.g., about 250 kPa or more, or about 300 kPa or more, or about 400 kPa or more, or about 500 kPa or more, or about 501 kPa or more, or about 600 kPa or more, or about 700 kPa or more, or about 800 kPa or more, or about 900 kPa or more, or about 1000 kPa or more, or about 1500 kPa or more, or about 2000 kPa or more, or about 2500 kPa or more, or about 3000 kPa or more, or about 3500 kPa or more. The method may include pressure casting the slip composition into a mold cavity at a pressure of about 4000 kPa or less, e.g., about 3500 kPa or less, or about 3500 kPa or less, or about 3000 kPa or less, or about 2500 kPa or less, or about 2000 kPa or less. The method may include pressure casting the slip composition into a mold cavity at a pressure of from about 200 kPa to about 4000 kPa, e.g., from about 200 kPa to about 3000 kPa, or from about 200 kPa to about 2000 kPa, or from about 200 kPa to about 1000 kPa, or from about 200 kPa to about 500 kPa, or from about 501 kPa to about 4000 kPa, or from about 1000 kPa to about 4000 kPa, or from about 2000 kPa to about 4000 kPa, or from about 3000 kPa to about 4000 kPa, or from about 2000 kPa to about 3000 kPa. Pressure casting may be low pressure casting, which may be defined as pressure casting in which the slip composition is cast at a pressure of about 200 kPa to about 5000 kPa. Pressure casting may be high pressure casting, which may be defined as pressure casting in which the slip composition is cast at a pressure of about 501 kPa to about 4000 kPa, for example, about 1000 kPa to about 4000 kPa, or about 2000 kPa to about 4000 kPa. A mold cavity can be understood to be the interior space of a mold that is filled with a slip composition. The mold cavity is typically surrounded by one or more mold walls. The mold wall(s) typically define the interior shape of the mold cavity and, in turn, the shape of the green sagger body. The mold may be a multi-part mold, i.e., the complete mold may be formed by fitting together two or more separate mold parts, each of which defines one or more portions of the interior of the mold cavity. The two or more mold parts may be held together (thus forming the mold cavity) during use, for example, using mechanical locking mechanisms, pneumatic pressure, hydraulic pressure, etc.

[0020] During pressure casting, the slip composition is injected under pressure through an inlet orifice into a mold cavity. Filtrate (i.e., liquid) is typically removed from the mold cavity (i.e., the slip composition within the mold cavity), increasing the concentration of solids (i.e., the solid components of the slip composition) within the mold cavity (i.e., within the slip composition within the mold cavity). Pressure casting is carried out until the (e.g., compacted) solids concentration in the mold cavity is high enough that a green sagger body is produced and can be safely removed from the mold without substantial damage or collapse. The filtrate may be removed from the mold cavity via one or more mold walls of the mold cavity. The mold walls may comprise (e.g., be formed of, or consist of) a porous or semi-porous material, such as plaster or a porous or semi-porous resin. Thus, the mold walls may absorb the filtrate from the mold cavity and / or allow the filtrate to flow through the mold walls.

[0021] Additionally or alternatively, the filtrate may be removed from the mold cavity via an outlet. The outlet may be formed in one or more mold walls, for example, at one end (e.g., the lower end) of the mold cavity. The outlet may be configured to prevent the passage of solid components of the slip composition therethrough. Thus, the outlet may be configured to function as a filter, allowing the passage of filtrate (i.e., liquid) therethrough while preventing the passage of solid components. In embodiments in which the filtrate is removed from the mold cavity via an outlet, the mold walls may comprise (e.g., be formed of or consist of) a non-porous material, such as a non-porous resin. In some cases (e.g., using low-pressure casting), pressure casting may be carried out for about 10 minutes or more, e.g., about 20 minutes or more, or about 30 minutes or more, or about 40 minutes or more. In some cases (e.g., using low-pressure casting), pressure casting may be carried out for about 60 minutes or less, e.g., about 50 minutes or less, or about 40 minutes or less, or about 30 minutes or less. In some cases (e.g., using low-pressure casting), pressure casting may be carried out for about 10 minutes to about 60 minutes, e.g., about 20 minutes to about 60 minutes, or about 30 minutes to about 60 minutes, or about 20 minutes to about 40 minutes, or about 20 minutes to about 30 minutes.

[0022] In some cases (e.g., using high pressure casting), pressure casting may be carried out for about 30 seconds or more, e.g., about 1 minute or more, or about 2 minutes or more, or about 3 minutes or more. In some cases (e.g., using high pressure casting), pressure casting may be carried out for about 10 minutes or less, e.g., about 8 minutes or less, or about 6 minutes or less, or about 5 minutes or less, or about 4 minutes or less, or about 3 minutes or less. In some cases (e.g., using high pressure casting), pressure casting may be carried out for approximately about 30 seconds to about 10 minutes, e.g., about 1 minute to about 8 minutes, or about 1 minute to about 6 minutes, or about 1 minute to about 5 minutes, or about 2 minutes to about 10 minutes, or about 2 minutes to about 5 minutes, or about 2 minutes to about 4 minutes, or about 2 minutes to about 3 minutes. Pressure can be applied to the slip composition using any suitable means known in the art. For example, mechanical, hydraulic, or pneumatic means can be used to apply pressure to the slip composition. The slip composition in the mold cavity can be directly pressurized, for example, by forcing the slip composition into the mold cavity under pressure and maintaining the pressure of the slip composition once it is in the mold cavity during the casting process. Additionally or alternatively, pressure can be applied (e.g., hydraulically) to the mold wall.

[0023] The method includes removing the green sagger body from the mold cavity after pressure casting. The green sagger body is also known as a sagger preform. Removing the green sagger body may include separating the mold parts from each other and / or from the green sagger body. The mold parts may be separated from each other and / or from the green sagger body by applying pressure (e.g., air or hydraulic pressure) and / or vacuum. After the green sagger body is removed from the mold cavity, one or more dry setters (eg, setter plates) may be applied.

[0024] The method may include the step of drying the green sagger body. The green sagger body may be dried by any suitable method, for example, at room temperature or at a temperature between 40°C and 100°C, for example about 60°C. The green sagger body may be dried for a period of 2 hours or more, or 6 hours or more, or 12 hours or more, or 18 hours or more, or 24 hours or more. The green sagger body may be considered dry when its moisture content is 0.5% by weight or less, based on the total weight of the green sagger body.

[0025] Slip Composition A slip may be understood to be a slurry used in the production of ceramics. Thus, the slip composition used in the method may comprise one or more layered silicate minerals and water. Layered silicate minerals include (but are not limited to) kaolin, calcined kaolin, smectite, illite, clay, calcined clay, talc, vermiculite, palygorskite, and / or sepiolite. Thus, the one or more layered silicate minerals in the slip composition may include kaolin, calcined kaolin, smectite, illite, clay, calcined clay, talc, vermiculite, palygorskite, sepiolite, and / or any combination thereof. The one or more layered silicate minerals in the slip composition may also comprise a blend of aluminosilicate minerals that have been fired at high temperatures (at least 1400°C), such as aluminosilicate chamotte, which is a blend of burnt clay and burnt kaolin. The slip composition may contain further ingredients in addition to one or more layered silicate minerals and water. For example, the slip composition may include one or more mineral components in addition to the layered silicate mineral. The slip composition may include alumina (Al2O3). The slip composition may include calcined alumina and / or uncalcined alumina. The slip composition may comprise corundum, a crystalline mineral form of alumina that may also contain trace amounts of iron, titanium, vanadium and / or chromium. The slip composition may include magnesium carbonate (MgCO3). The slip composition may include magnesite, a mineral form of magnesium carbonate that may also contain trace amounts of iron, manganese, cobalt and / or nickel.

[0026] The slip composition may include mullite and / or kyanite. Mullite, also known as porcellanite, has the chemical formula Al6Si2O 13 and can occur naturally or be produced, such as by calcining kaolinite or kyanite. Kyanite is a high-pressure polymorph of andalusite and sillimanite.

[0027] The slip composition may include spinel. Spinels are defined as a group of minerals of the general formula AB2X4 that crystallize in a cubic crystal system, where the X anions are arranged in a cubic packed lattice and the A and B cations occupy octahedral and / or tetrahedral sites. Spinels include a specific mineral known as "spinel," i.e., MgAl2O4. Thus, the slip composition may include spinel (MgAl2O4). Spinels may be naturally occurring or manufactured. For example, the spinel may be fused magnesium-aluminate spinel. Thus, the slip composition may include one or more layered silicate minerals, water, and one or more of alumina, e.g., calcined alumina, corundum, magnesium carbonate, e.g., magnesite, mullite, kyanite, spinel, and / or any combination thereof. The slip composition may comprise one or more layered silicate minerals, mullite, and water. The slip composition may comprise one or more layered silicate minerals, alumina and / or corundum, mullite and water. The slip composition may include one or more of kaolin, talc, mullite, and water. The slip composition can be selected to produce cordierite and mullite during the firing process, which can give the sager good chemical resistance at a reasonable cost.

[0028] The slip composition may include one or more additives. For example, the slip composition may include a deflocculating agent and / or a binding agent. For example, the slip composition may include a polycarboxylic acid (e.g., DOLAPIX PC 67, available from Zschimmer & Schwarz GmbH Co., Germany), a polysaccharide (e.g., COLLSTAB® W-60 gellan gum, available from COLLTEC GmbH & Co., Germany), and / or a lignosulfonate (e.g., LignoBond® DD, available from Borregaard, Norway).

[0029] Alternatively, the slip composition may comprise about 70% by weight or more, e.g., about 73% by weight or more, or about 75% by weight or more, or about 78% by weight or more, or about 80% by weight or more, of layered silicate based on its total dry weight. The slip composition may comprise about 90% by weight or less, e.g., about 87% by weight or less, or about 85% by weight or less, of layered silicate mineral based on its total dry weight. The slip composition may comprise from about 70% to about 90% by weight, or from about 73% to about 87% by weight, or from about 75% to about 87% by weight, or from about 78% to about 87% by weight, or from about 78% to about 85% by weight, or from about 80% to about 85% by weight, of layered silicate mineral based on its total dry weight. Applicants have found that, advantageously, by using pressure casting in the range of 200 kPa to 4000 kPa, the concentration of alumina can be reduced in the slip without adversely affecting the mechanical performance of the fired sagger, which means that the sagger can be made lighter, since alumina contributes significantly to the mass of the sagger.

[0030] The slip composition may comprise about 1% by weight or more, e.g., about 2% by weight or more, or about 3% by weight or more, or about 4% by weight or more, or about 5% by weight or more, or about 10% by weight or more, or about 12% by weight or more alumina (e.g., calcined alumina) based on its total dry weight. The slip composition may comprise about 30% by weight or less, or about 25% by weight or less, or about 20% by weight or less, or about 15% by weight or less, or about 10% by weight or less, or about 5% by weight or less alumina (e.g., calcined alumina) based on its total dry weight. The slip composition may comprise from about 1% to about 30% by weight, e.g., from about 1% to about 25% by weight, or from about 1% to about 20% by weight, or from about 1% to about 15% by weight, or from about 1% to about 10% by weight, or from about 1% to about 5% by weight alumina (e.g., calcined alumina) based on its total dry weight. The slip composition may be completely free of corundum, or alternatively, the slip composition may include corundum.

[0031] The slip composition may comprise about 5% by weight or more, e.g., about 10% by weight or more, or about 15% by weight or more, of corundum based on its total dry weight. The slip composition may comprise about 30% by weight or less, or about 20% by weight or less, or about 10% by weight or less of corundum based on its total dry weight. The slip composition may comprise from about 5% to about 30% by weight, e.g., from about 5% to about 20% by weight, or from about 5% to about 10% by weight of corundum based on its total dry weight.

[0032] The slip composition may be completely free of mullite. The slip composition may be completely free of kyanite. Alternatively, the slip composition may include mullite and / or kyanite. The slip composition may include about 5% by weight or more of mullite and / or kyanite, e.g., about 8% by weight or more, or about 10% by weight or more, or about 12% by weight or more, based on the total dry weight of the slip composition. The slip composition may include about 30% by weight or less, or about 25% by weight or less, or about 20% by weight or less, or about 17% by weight or less, or about 15% by weight or less of mullite and / or kyanite, based on the total dry weight of the slip composition. The slip composition may include about 5% to about 30%, or about 5% to about 25%, or about 5% to about 20%, or about 5% to about 17%, or about 5% to about 15%, by weight of mullite and / or kyanite, based on the total dry weight of the slip composition.

[0033] The slip composition may be spinel-free. Alternatively, the slip composition may include spinel. The slip composition may contain about 0.1% by weight or more, e.g., about 1% by weight or more, or about 1.5% by weight or more, of spinel based on its total dry weight. The slip composition may contain about 25% by weight or less, e.g., about 10% by weight or less, or about 5% by weight or less, or about 4% by weight or less, of spinel based on its total dry weight. The slip composition may contain from about 0% to about 25%, or from about 0% to about 15%, or from about 0% to about 10%, or from about 0% to about 5%, or from about 0.1% to about 5%, or from about 0% to about 4%, or from about 0% to about 3%, or from about 0.1% to about 3%, by weight of spinel based on its total dry weight.

[0034] The slip composition may comprise from about 0.01% to about 1.5% by weight, e.g., from about 0.01% to about 1.0% by weight, or from about 0.01% to about 0.9% by weight, or from about 0.01% to about 0.8% by weight, or from about 0.01% to about 0.5% by weight, or from about 0.01% to about 0.4% by weight, or from about 0.01% to about 0.3% by weight, or from about 0.01% to about 0.2% by weight, or from about 0.01% to about 0.1% by weight of deflocculating agent and / or binder, based on the total dry weight of the slip composition. The slip composition may comprise from about 8% to about 30% by weight of water, e.g., from about 8% to about 25% by weight, or from about 10% to about 25% by weight, or from about 12% to about 18% by weight, or from about 18% to about 25% by weight, or from about 20% to about 22% by weight, based on its total dry weight. The water and deflocculating agent and / or binder content of the slip composition may be adjusted to achieve a desired consistency (defined in terms of viscosity parameters such as thixotropy) suitable for pressure casting. The slip composition may comprise, based on its total dry weight, about 70% to about 90%, e.g., about 75% to about 85%, by weight of the layered silicate mineral, about 1% to about 10%, e.g., about 2% to about 8%, by weight of alumina (e.g., calcined alumina), and about 5% to about 20%, e.g., about 10% to about 29%, by weight of mullite. The slip composition may have a density of from about 1500 g / L to about 3000 g / L, for example, from about 1800 g / L to about 3000 g / L, or from about 2000 g / L to about 3000 g / L, or from about 2000 g / L to about 2100 g / L, or from about 2500 g / L to about 2700 g / L.

[0035] The slip composition, as measured by a Gallenkamp universal torsional viscometer at a first viscosity (i.e., overswing) measured immediately after stirring and a second viscosity (i.e., overswing) measured 5 minutes after stirring, has a viscosity of from about 15° G to about 30° G, e.g., from about 15° G to about 27.5° G, or from about 15° G to about 25° G, or from about 15° G to about 22.5° G, or from about 15° G to about 20° G, or from about 15° G to about 17.5° G, or from about 17.5° G to about 30° G, Alternatively, it may have a thixotropy of about 17.5°G to about 25°G, or about 17.5°G to about 22.5°G, or about 17.5°G to about 20°G, or about 20°G to about 30°G, or about 20°G to about 27.5°G, or about 20°G to about 25°G, or about 20°G to about 22.5°G, or about 22.5°G to about 30°G, or about 22.5°G to about 27.5°G, or about 22.5°G to about 25°G, or about 25°G to about 30°G, or about 25°G to about 27.5°G, or about 27.5°G to about 30°G.

[0036] The slip composition may have a moisture content of from about 10% to about 30% by weight, e.g., from about 10% to about 25% by weight, or from about 10% to about 20% by weight, or from about 10% to about 15% by weight, or from about 15% to about 30% by weight, or from about 15% to about 25% by weight, or from about 15% to about 20% by weight, or from about 20% to about 30% by weight, or from about 20% to about 25% by weight, or from about 25% to about 30% by weight, based on the total weight of the slip composition. Baking process The method includes baking a green sagger body (also known as a preform) to produce a baked sagger body. The green sagger body can be fired in any suitable type of kiln or furnace known in the art.

[0037] The green sagger body may be fired at a temperature of about 1200°C or higher, or about 1300°C or higher, or about 1325°C or higher, or about 1350°C or higher. The green sagger body may be fired at a temperature of about 1500°C or lower, for example, about 1450°C or lower, or about 1400°C or lower. The green sagger body may be fired at a temperature of about 1200°C to about 1500°C, for example, about 1200°C to about 1400°C, or about 1300°C to about 1400°C. The green sagger body may be baked for about 12 hours or more, such as about 15 hours or more, or about 18 hours or more, or about 21 hours or more, or about 24 hours or more, or about 27 hours or more, or 30 hours or more. Baked sagar body composition It will be appreciated that during the firing process, the components of the slip composition from which the green sagger body is formed react to form a ceramic material which, upon cooling, defines the fired sagger body. The chemical composition of the fired sagar bodies can be determined by XRD. The sagar (i.e., the fired sagar body) may contain about 40% to about 60% by weight, for example, about 45% to about 60% by weight, or about 45% to about 55% by weight, or about 45% to about 52% by weight, or about 47% to about 52% by weight, of SiO2 based on its total weight.

[0038] The sagger, i.e., the fired sagger body, may contain about 10% to about 50% by weight Al2O3, based on its total weight, for example, about 10% to about 45% by weight, or about 20% to about 50% by weight, or about 20% to about 45% by weight, or about 30% to about 50% by weight, or about 30% to about 45% by weight, or about 35% to about 45% by weight. Sagar, i.e., fired sagar body, typically comprises SiO2 and Al2O3. In addition to SiO2 and Al2O3, the sagger, i.e., the fired sagger body, may contain one or more of Fe2O3, TiO2, CaO, MgO, K2O, and Na2O.

[0039] The sagger, i.e., the fired sagger body, may contain about 2.0% by weight or less Fe2O3, e.g., about 1.5% by weight or less, or about 1.0% by weight or less, or about 0.5% by weight or less, based on its total weight. The sagger, i.e., the fired sagger body, may contain about 0.1% by weight or more Fe2O3, based on its total weight. The sagger, i.e., the fired sagger body, may contain about 0.1% to about 2.0% by weight Fe2O3, e.g., about 0.1% to about 1.5% by weight, or about 0.1% to about 1.0% by weight, or about 0.1% to about 0.5% by weight, based on its total weight. The sagger, i.e., the fired sagger body, may contain about 1.0 wt.% or less TiO2, e.g., about 0.5 wt.% or less, or about 0.1 wt.% or less, based on its total weight. The sagger, i.e., the fired sagger body, may contain about 0.05 wt.% or more TiO2, based on its total weight. The sagger, i.e., the fired sagger body, may contain about 0.05 wt.% to about 1.0 wt.% TiO2, e.g., about 0.05 wt.% to about 0.5 wt.%, or about 0.05 wt.% to about 0.1 wt.% TiO2, based on its total weight.

[0040] The sagger, i.e., the fired sagger body, may contain about 1.0% by weight or less, e.g., about 0.5% by weight or less, or about 0.1% by weight or less, of CaO, based on its total weight. The sagger, i.e., the fired sagger body material, may contain about 0.01% to about 1.0% by weight, e.g., about 0.01% to about 0.5% by weight, or about 0.01% to about 0.1% by weight, or about 0.05% to about 1.0% by weight, or about 0.05% to about 0.5% by weight, or about 0.05% to about 0.1% by weight, based on its total weight.

[0041] The sagger, i.e., the fired sagger body, may comprise about 4% by weight or more MgO, e.g., about 5% by weight or more, or about 6% by weight or more, or about 7% by weight or more, or about 8% by weight or more, or about 9% by weight or less, based on its total weight. The sagger, i.e., the fired sagger body, may comprise about 10% by weight or less MgO, e.g., about 9% by weight or less, or about 8% by weight or less, or about 7% by weight or less, or about 6% by weight or less, or about 5% by weight or less, based on its total weight. The sagger, i.e., the baked sagger body, has a total mass of about 4% to about 10% by mass, for example, about 4% to about 9% by mass, or about 4% to about 8% by mass, or about 4% to about 7% by mass, or about 4% to about 6% by mass, or about 4% to about 5% by mass, or about 5% to about 10% by mass, or about 5% to about 9% by mass, or about 5% to about 8% by mass, or about 5% to about 7% by mass, Alternatively, it may contain about 5% by mass to about 6% by mass, or about 6% by mass to about 10% by mass, or about 6% by mass to about 9% by mass, or about 6% by mass to about 8% by mass, or about 6% by mass to about 7% by mass, or about 7% by mass to about 10% by mass, or about 7% by mass to about 9% by mass, or about 7% by mass to about 8% by mass, or about 8% by mass to about 10% by mass, or about 8% by mass to about 9% by mass, or about 9% by mass to about 10% by mass of MgO.

[0042] The saggar, i.e., the baked saggar body, may contain about 2.0% by weight or less of KO, e.g., about 1.5% by weight or less, or about 1.0% by weight or less, or about 0.5% by weight or less, or about 0.1% by weight or less, based on its total weight. The saggar, i.e., the baked saggar body, may contain about 0.01% by weight or more of KO, based on its total weight. The saggar, i.e., the baked saggar body, may contain about 0.01% by weight to about 2.0% by weight of KO, e.g., about 0.01% by weight to about 1.5% by weight, or about 0.01% by weight to about 1.0% by weight, or about 0.01% by weight to about 0.5% by weight, or about 0.01% by weight to about 0.1% by weight of KO, based on its total weight.

[0043] The sagger, i.e., the baked sagger body, may contain about 0.5% by weight or less NaO, e.g., about 0.1% by weight or less, or about 0.05% by weight or less, based on its total weight. The sagger, i.e., the baked sagger body, may contain about 0.01% by weight or more NaO, based on its total weight. The sagger, i.e., the baked sagger body, may contain about 0.01% to about 0.5% by weight NaO, e.g., about 0.01% to about 0.1% by weight, or about 0.01% to about 0.05% by weight NaO, based on its total weight. The sagger, ie, fired sagger body, may comprise, based on its total weight, about 20 to about 55 wt. % mullite and about 30 to about 45 wt. % cordierite, and about 0 to 25 wt. % spinel. The sagger, ie, the fired sagger body, may contain about 20 to about 55% by weight of mullite and about 30 to about 45% by weight of cordierite, based on its total weight, and may be free of spinel. The sagger, ie, fired sagger body, may comprise, based on its total weight, about 20 to about 55 wt. % mullite and about 30 to about 45 wt. % cordierite, and about 0.1 to 4 wt. % spinel.

[0044] The sagger (i.e., the baked sagger body) may have a modulus of rupture (MOR) of about 16 MPa or more, e.g., about 18 MPa or more, or about 20 MPa or more, or about 21 MPa or more, or about 22 MPa or more, or about 23 MPa or more, or about 24 MPa or more, or about 25 MPa or more, or about 26 MPa or more, or about 27 MPa or more. The sagger (i.e., the baked sagger body) may have a modulus of rupture (MOR) of about 16 MPa to about 35 MPa, e.g., about 20 MPa to about 35 MPa, or about 21 MPa to about 35 MPa, or about 22 MPa to about 35 MPa, or about 23 MPa to about 35 MPa, or about 24 MPa to about 35 MPa, or about 25 MPa to about 35 MPa. The MOR can be measured by a three-point bending test according to BS EN 993-6 1999. Standard bars measuring 125 x 20 x 20 mm are cut from the baked samples for testing. Measurements are performed using an MTS QTEST / 10 device. The sagar (ie, the fired sagar body) may contain about 5% to about 30% by weight, for example about 7% to about 25% by weight, or about 10% to about 20% by weight of amorphous phase based on its total weight.

[0045] The sagar (i.e., the baked sagar body) may have a water absorption of about 5% to about 20%, for example, about 7% to about 20%, or about 10% to about 20%, or about 7% to about 16%, or about 8% to about 15%, or about 9% to about 11%, or about 8% to about 10%, or about 9% to about 10%, or about 13% to about 16%, or about 13% to about 15%, or about 14% to about 15%, based on its total mass. Water absorption can be measured according to BS EN 993-1.

[0046] The sagger (i.e., the baked sagger body) is approximately 1.6 g / cm 3 ~About 3.0g / cm 3 , for example, about 1.6 g / cm 3 ~Approx. 2.9g / cm 3 , about 1.6g / cm 3 ~Approx. 2.8g / cm 3 , or about 1.6 g / cm 3 ~Approx. 2.7g / cm 3 , or about 1.6 g / cm 3 ~2.6g / cm 3 , or about 1.6 g / cm 3 ~Approx. 2.5g / cm 3 , or about 1.6 g / cm 3 ~approx. 2.4g / cm 3 , or about 1.6 g / cm 3 ~Approx. 2.3g / cm 3 , or about 1.6 g / cm 3 ~Approx. 2.2g / cm 3 , or about 1.6 g / cm 3 ~Approx. 2.1g / cm 3 , or about 1.6 g / cm 3 ~Approx. 2.0g / cm 3 , or about 1.7 g / cm 3 ~About 3.0g / cm 3 , or about 1.8 g / cm 3 ~About 3.0g / cm 3 , or about 1.9 g / cm 3~About 3.0g / cm 3 , or about 2.0 g / cm 3 ~About 3.0g / cm 3 , or about 2.1 g / cm 3 ~About 3.0g / cm 3 , or about 2.2 g / cm 3 ~About 3.0g / cm 3 , or about 2.3 g / cm 3 ~About 3.0g / cm 3 , or about 2.4 g / cm 3 ~About 3.0g / cm 3 , or about 2.5 g / cm 3 ~About 3.0g / cm 3 , or about 1.8 g / cm 3 ~Approx. 2.8g / cm 3 , or about 1.8 g / cm 3 ~Approx. 2.0g / cm 3 , or about 1.9 g / cm 3 ~Approx. 2.1g / cm 3 , or about 2.5 g / cm 3 ~Approx. 2.7g / cm 3 , or about 2.6 g / cm 3 ~Approx. 2.7g / cm 3 The density may be measured in accordance with BS EN 993-1. The sagar (i.e., the fired sagar body) may have a porosity of about 16% to about 35%, for example, or about 20% to about 35%, or about 20% to about 30%, or about 22% to about 30%, or about 23% to about 30%, or about 24% to about 30%, or about 24% to about 29%, based on the total volume of the sagar. Porosity can be measured in accordance with BS EN 993-1.

[0047] The sagger (i.e., the baked sagger body) is approximately 1.5 x 10 -6 K -1 ~Approx. 8.0×10 -6 K -1 , for example, about 1.5 x 10 -6 K -1 ~Approx. 7.5×10 -6 K -1 , or approximately 1.5 × 10 -6 K -1 ~Approx. 3.0×10 -6K -1 , or approximately 1.5 × 10 -6 K -1 ~Approx. 2.5×10 -6 K -1 , or approximately 2.0 × 10 -6 K -1 ~Approx. 3.0×10 -6 K -1 , or approximately 2.0 × 10 -6 K -1 ~Approx. 2.5×10 -6 K -1 , or approximately 5.5 × 10 -6 K -1 ~Approx. 7.0×10 -6 K -1 , or approximately 6.0 × 10 -6 K -1 ~Approx. 7.5×10 -6 K -1 , or approximately 6.0 × 10 -6 K -1 ~Approx. 7.0×10 -6 K -1 , or approximately 6.0 × 10 -6 K -1 ~Approx. 6.5×10 -6 K -1 The thermal expansion coefficient can be measured according to EN 821-1 1998 using a Netsch DIL 402 PC / 4 dilatometer at a maximum operating temperature of 1600°C.

[0048] It will be understood that the present invention is not limited to the above-described embodiments, and that various modifications and improvements can be made without departing from the scope of the concepts described herein. Any feature can be used alone or in any combination with other features, unless they are mutually exclusive, and the present disclosure extends to and includes all combinations and subcombinations of one or more features described herein. [Example]

[0049] Example 1 Two ceramic slips, S1 and S2, were prepared with the compositions shown in Tables 1 and 2, respectively. A third (comparative) ceramic slip, S3, with a higher alumina content was also prepared. The slips were mixed in a conventional mixer equipped with a shear plunger. The water and deagglomerating agent contents were determined to give viscosity parameters suitable for casting.

[0050] In the table below, Kaolin: kaoPearl CNL 30, available from Imerys Clay: RR40, BS5 and Hymod excelsior, available from Imerys Talc: Talc 2C, available from Imerys Calcined alumina: Alo G4 4G, available from Mal Mullite: Virgina Mullte -100, available from Kyanite Mining corporation Chamotte: Molochite-30, available from Imerys Spinel: F27-100, available from Motim Fused cast refractories Corundum: Korund ESK-A -1, available from Motim Gellan gum is Collstab W-60 gellan gum, available from COLLTEC GmbH & Co. The lignosulfonate is Lignobond DD lignosulfonate, available from Borregaard The polycarboxylic acid is DOLAPIX PC 67, available from Zschimmer & Schwarz GmbH Co.

[0051] [Table 1]

[0052] [Table 2]

[0053] [Table 3]

[0054] For each slip composition, the following physical properties were measured: density, deflection angle at 0 minutes, 5 minutes as measured by a Gallenkamp universal torsional viscometer, and thixotropy, which is the difference between the deflection angle at 0 minutes and the deflection angle at 5 minutes. The results are shown in Table 4. [Table 4]

[0055] Three dry ceramic press compositions P1 to P3 were also prepared having the compositions shown in Tables 5 to 7, respectively. [Table 5]

[0056] [Table 6]

[0057] [Table 7]

[0058] The following physical property was measured for each press composition: moisture content. Details of the measurement methods are provided elsewhere in this specification. The results are shown in Table 8. [Table 8]

[0059] Two saggers were prepared using slip compositions S1 and S2 in a high-pressure casting process. In each case, high-pressure casting was performed using a resin mold fitted to a high-pressure casting machine with a movable top, a fixed bottom frame, and two movable sides. The mold was closed by applying a maximum vertical hydraulic pressure of 240 bar and a maximum horizontal hydraulic pressure of 160 bar. Casting was performed at an operating pressure of 35 bar (3500 kPa). Each sagger required approximately 3 minutes to cast. After casting, the green bodies were demolded and dried at 60°C for 24 hours, then baked in a kiln at 1350°C for 24 hours and allowed to cool. A comparative sagger with an alumina content of approximately 80% by mass was also prepared under the same conditions.

[0060] The following physical properties were measured for each of the fired saggers: modulus of rupture (MOR), water absorption, density, porosity, coefficient of thermal expansion (CTE) as measured by Netzsch DIL 402CD, and chemical composition. Details of the measurement methods are provided elsewhere in this specification. The results are shown in Table 9.

[0061] [Table 9] The comparative sagger has a similar MOR but a mass of over 5 kg and a density of 2.66 g / cm 3 is.

[0062] Two saggers were prepared using slip compositions S1 and S2 in a low-pressure casting process. In each case, low-pressure casting was performed using a plaster mold fitted to a low-pressure casting machine with a steel frame, movable top and bottom frames, and a fixed center frame. Vertical movement was mechanical, and horizontal movement was mechanical and pneumatic. In the vertical position, the mold was closed by a mechanical lock and then pneumatically. In the horizontal position, the mold was closed hydraulically. Casting was performed at an operating pressure of 2 bar (200 kPa). Each sagger took approximately 20 to 30 minutes to cast. After casting, the green bodies were demolded, dried at 60°C for 24 hours, and then kiln-kilned at 1350°C for 24 hours, after which they were allowed to cool. A comparative sagger with an alumina content of about 80% by mass also exhibits S comp The slip compositions were prepared under the same conditions.

[0063] The following physical property was measured for each of the fired saggers: Modulus of Rupture (MOR). Details of the measurement methods are provided elsewhere in this specification. The results are shown in Table 10. [Table 10] Three saggers were prepared using press compositions P1, P2 and P3 in the pressing process. After casting, the green bodies were demolded, dried at 60°C for 24 hours, fired in a kiln at 1350°C for 24 hours, and then allowed to cool.

[0064] The following physical properties were measured for each of the fired saggers: modulus of rupture (MOR), water absorption, density, porosity, coefficient of thermal expansion (CTE), and chemical composition. Details of the measurement methods are provided elsewhere in this specification. The results are shown in Table 11. [Table 11]

[0065] Example 2 The same ceramic slip compositions S1 and S2 and a comparative ceramic slip composition were prepared as described in Example 1. The slip composition was used to prepare saggers in a high pressure casting process as described in Example 1. Example 2 differs in that the thickness of the saggers prepared was 9 mm.

[0066] The following physical properties were measured for each of the fired saggers: modulus of rupture (MOR), water absorption, density, porosity, coefficient of thermal expansion (CTE) as measured by Netzsch DIL 402CD, and chemical composition. Details of the measurement methods are provided elsewhere in this specification. The results are shown in Table 12.

[0067] [Table 12] The same slip compositions S1, S2 and S3 were cast in the low pressure casting process described in Example 1. comp Example 2 differs in that the thickness of the prepared sagger is 9 mm.

[0068] The modulus of rupture (MOR) was measured for each fired saggar. Details of the measurement method are provided elsewhere in this specification. The results are shown in Table 13. [Table 13]

Claims

1. 1. A sagger having a body with a bottom and one or more side walls, the bottom and the one or more side walls have a thickness of about 13 mm or less, e.g., about 10 mm or less; The sagger contains about 50% by weight or less of Al based on its total weight. 2 O 3 , preferably about 45% by weight or less of Al 2 O 3 Including, Approximately 1.6g / cm 3 ~Approx. 3.0g / cm 3 , for example, about 1.6 g / cm 3 ~Approx. 2.3g / cm 3 and / or Approximately 1.5×10 -6 K -1 ~Approx. 5.0×10 -6 K -1 , for example, about 2.0×10 -6 K -1 ~Approx. 4.0×10 -6 K -1 and / or and / or a modulus of rupture of about 15 MPa or more, e.g., about 20 MPa or more, or about 23 MPa or more, as measured by a three-point bending test according to BS EN 993-6 1999; The sagger has a modulus of rupture to thickness ratio of about 1.5 MPa / mm or more, for example, about 2.0 MPa / mm or more, preferably in the range of 1.5 MPa / mm to 4.0 MPa / mm.

2. 10. The sager of claim 1 comprising, by weight, about 20 to about 55% mullite, about 30 to about 45% cordierite, and about 0 to 25% spinel, preferably about 0 to about 5% spinel, based on the total weight of the sager.

3. 4. The sager of claim 2 or 3, comprising about 5% to about 30% by weight of an amorphous phase, based on the total weight of the sager.

4. the sagger has a water absorption rate of about 5% to about 20%, e.g., about 8% to about 16%, based on its total mass; and / or About 40% to about 60% by weight of SiO based on the total weight 2 and about 30% to about 50% by weight of Al, based on the total weight of the 2 O 3 Including, Fe, about 2.0% by weight or less, for example, about 0.1% to about 2.0% by weight, based on the total weight of the 2 O 3 , about 1.0 wt % or less, for example, about 0.05 wt % to about 1.0 wt % TiO based on the total weight thereof 2 , about 1.0% by weight or less, for example, about 0.01% to about 1.0% by weight of CaO, about 4% to about 10% by weight of MgO, and about 2.0% by weight or less, for example, about 0.01% to about 2.0% by weight of K, based on the total weight. 2 O, and / or about 0.5% by weight or less, for example, about 0.01% by weight to about 0.5% by weight of Na, based on the total weight thereof. 2 The sager according to any one of claims 1 to 3, which may contain O.

5. 5. A sagger according to any one of claims 1 to 4 for retaining powder during firing, for example for retaining battery electrode material powder such as battery cathode material powder, for example for retaining oxides, hydroxides, carbonates, sulphates and / or phosphates of one or more of lithium, titanium, vanadium, chromium, manganese, iron, cobalt, tungsten and / or nickel.

6. A method for producing a sager according to any one of claims 1 to 5 for use in a kiln, comprising the steps of: pressure casting the slip composition in a mold cavity at a pressure of about 200 kPa to about 4000 kPa to form a green sagger body; removing the green sagger body from the mold cavity; baking the green sagger body to produce a baked sagger body; A method comprising:

7. 7. The method according to claim 6, wherein the pressure casting is low pressure casting or high pressure casting, preferably high pressure casting.

8. 8. The method of claim 6 or claim 7, wherein during pressure casting of the slip composition in the mold cavity, filtrate is removed from the mold cavity via an outlet configured to prevent flow therethrough of solid components of the slip composition.

9. the slip composition comprises one or more layered silicate minerals and water; the one or more layered silicate minerals include: kaolin, calcined kaolin, smectite, illite, clay, calcined clay, talc, vermiculite, palygorskite, sepiolite, and / or any combination thereof; 9. A method according to any one of claims 6 to 8, wherein the slip composition comprises: alumina, e.g., calcined alumina, corundum, magnesium carbonate, e.g., magnesite, mullite, kyanite, spinel, and / or any combination thereof, preferably the slip composition comprises kaolin, calcined kaolin, talc, calcined alumina, corundum, mullite and / or calcined clay, and / or any combination thereof.

10. 10. The method of claim 9, wherein the slip composition comprises about 70% to about 90%, e.g., about 75% to about 85%, by weight, of the layered silicate mineral, about 1% to about 10%, e.g., about 2% to about 8%, by weight, of alumina (e.g., calcined alumina), and about 5% to about 20%, e.g., about 10% to about 29%, by weight, of mullite.

11. The method of any one of claims 6 to 10, wherein the green sagger body is fired at a temperature of about 1300°C to about 1450°C.

12. A sagar obtainable by the method according to any one of claims 6 to 11.

Images