摘要:
A hard drive disk substrate is formed of a multi-phase ceramic-based material having at least two phases with amorphous phases being present in an amount less than about 1 volume percent based on the volume of the ceramic-based material or at least one phase being free metal. A process for producing the ceramic-based disk substrate is produced by forming a flat disk of a porous ceramic and then infiltrating the porous ceramic with a metal whereby a multi-phase ceramic-based computer hard drive disk is produced. Additionally, a step of passivating the porous ceramic by elevating it to a temperature of about 1300.degree. to about 1800.degree. C. before the infiltrating step may be performed, such that the surfaces are passivated and the reaction kinetics can be controlled during the infiltrating step. A preferred composite material is made of a multi-phase boron carbide composite material including grains having peaks with an average roughness value, Ra, of between about 1 to about 200.ANG., the roughness value being formed in situ by causing a micro hardness gradient of between about 19 and about 3200 Kg/mm.sup.2 in the various phases of the multi-phase boron carbide composite material.
摘要翻译:硬盘驱动器盘基板由具有至少两相的多相陶瓷基材料形成,其中无定形相以基于陶瓷基材料的体积或至少一相的量存在的量小于约1体积% 是免费金属。 通过形成多孔陶瓷的平板,然后用金属渗透多孔陶瓷来制造陶瓷基盘基板的方法,由此制造多相陶瓷基计算机硬盘驱动盘。 此外,可以在渗透步骤之前将其升高至约1300℃至约1800℃的温度来钝化多孔陶瓷的步骤,使得表面被钝化,并且可以在渗透步骤期间控制反应动力学 。 优选的复合材料由多相碳化硼复合材料制成,其包括具有平均粗糙度值Ra的峰值在约1至约200之间的晶粒,该粗糙度值通过使原位形成的微观硬度梯度 在多相碳化硼复合材料的各个相中约19至约3200Kg / mm 2。
摘要:
A hard drive disk substrate is formed of a multi-phase ceramic-based material having at least two phases with amorphous phases being present in an amount less than about 1 volume percent based on the volume of the ceramic-based material or at least one phase being free metal. A process for producing the ceramic-based disk substrate is produced by forming a flat disk of a porous ceramic and then infiltrating the porous ceramic with a metal whereby a multi-phase ceramic-based computer hard drive disk is produced. Additionally, a step of passivating the porous ceramic by elevating it to a temperature of about 1300.degree. to about 1800.degree. C. before the infiltrating step may be performed, such that the surfaces are passivated and the reaction kinetics can be controlled during the infiltrating step. A preferred composite material is made of a multi-phase boron carbide composite material including grains having peaks with an average roughness value, Ra, of between about 1 to about 200 .ANG., the roughness value being formed in situ by causing a micro hardness gradient of between about 19 and about 3200 Kg/mm.sup.2 in the various phases of the multi-phase boron carbide composite material.
摘要翻译:硬盘驱动器盘基板由具有至少两相的多相陶瓷基材料形成,其中无定形相以基于陶瓷基材料的体积或至少一相的量存在的量小于约1体积% 是免费金属。 通过形成多孔陶瓷的平板,然后用金属渗透多孔陶瓷来制造陶瓷基盘基板的方法,由此制造多相陶瓷基计算机硬盘驱动盘。 此外,可以在渗透步骤之前将其升高至约1300℃至约1800℃的温度来钝化多孔陶瓷的步骤,使得表面被钝化,并且可以在渗透步骤期间控制反应动力学 。 优选的复合材料由多相碳化硼复合材料制成,其包括具有平均粗糙度值Ra的峰值在约1至约200之间的晶粒,该粗糙度值通过使原位形成的微观硬度梯度 在多相碳化硼复合材料的各个相中约19至约3200Kg / mm 2。
摘要:
A porous mullite composition is made by Forming a mixture of one or more precursor compounds having the elements present in mullite (e.g., clay, alumina, silica) and a property enhancing compound. The property enhancing compound is a compound having an element selected from the group consisting of Mg, Ca, Fe, Na, K, Ce, Pr, Nd, Sm, Eu, Gd, Th, Dy, Ho, Er, Tm, Yb, Lu, B, Y, Sc, La and combination thereof. The mixture is shaped and to form a porous green shape which is heated under an atmosphere having a fluorine containing gas to a temperature sufficient to form a mullite composition comprised substantially of acicular mullite grains that are essentially chemically bound.
摘要:
A porous mullite composition is made by forming a mixture of one or more precursor compounds having the elements present in mullite (e.g., clay, alumina, silica) and a property enhancing compound. The property enhancing compound is a compound having an element selected from the group consisting of Mg, Ca, Fe, Na, K, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, B, Y, Sc, La and combination thereof. The mixture is shaped and to form a porous green shape which is heated under an atmosphere having a fluorine containing gas to a temperature sufficient to form a mullite composition comprised substantially of acicular mullite grains that are essentially chemically bound.
摘要:
The present invention generally relates to a geopolymer precursor dry mixture, geopolymer precursor package, a process of preparing a geopolymer composition, and a method of providing a geopolymer composition to a geopolymer composition preparation site.
摘要:
The present invention relates to modified geopolymer compositions, geopolymer-coated organic polymer substrates, and methods of manufacturing and articles comprising same.
摘要:
A process for preparing complex-shaped, ceramic-metal composite articles, comprising:a) contacting a non-wettable powder that is non-wetting to a metal to be used for infiltration with a shaped ceramic body to form a layer(s) of the non-wettable powder on one or more surface(s) of the shaped ceramic body wherein the shaped ceramic body has a region(s) where there is no layer of the non-wettable powder;b) infiltrating the shaped ceramic body with the metal through the region(s) where there is no layer of the non-wettable powder such that a complex-shaped ceramic-metal composite comprising one or more metal phases and one or more ceramic phases is formed, wherein the article has substantially the net shape of the shaped ceramic body and the undesirable regions of excess metal on the surface and undesirable phases within the complex-shaped ceramic-metal composite article near the surface are located only in the region(s) where there is no layer of the non-wettable powder.A complex-shaped ceramic-metal composite article with undesirable regions of excess metal and undesirable phases on the surface(s) of or within the article only where there is or was no layer of non-wettable powder.The process of the invention allows the preparation of complex-shaped ceramic-metal composite articles with undesirable regions of excess metal and undesirable phases on the surface(s) of or within the article only in the regions where there is or was no layer of non-wettable powder. The process of the invention allows the preparation of a complex-shaped ceramic-metal composite article which requires little or no machining of the surface(s) to achieve a finished article. A complex-shaped ceramic-metal composite article is prepared which contains few undesirable regions of excess metal and undesirable phases.
摘要:
The present invention relates to modified geopolymer compositions, geopolymer-coated organic polymer substrates, and methods of manufacturing and articles comprising same.
摘要:
A ceramic-metal composite that is tough and stiff has been prepared and is comprised of an inert ceramic (e.g., alumina) embedded and dispersed in a matrix comprised of a metal (e.g., aluminum), a reactive ceramic (e.g., boron carbide) and a reactive ceramic-metal reaction product (e.g., AlB2, Al4BC, Al3B48C2, AlB12, Al4C3, AlB24C4 or mixtures thereof) wherein grains of the inert ceramic have an average grain size greater than or equal to the average grain size of grains of the reactive ceramic. The ceramic-metal composite may be prepared by forming a mixture comprised of an inert ceramic powder (e.g., alumina) and a reactive ceramic powder (e.g., boron carbide), the inert ceramic powder having an average particle size equal to or greater than the average particle size of the reactive ceramic powder, forming the mixture into a porous body and consolidating the porous body in the presence of a metal (e.g., aluminum) to form the ceramic-metal composite.
摘要:
A process for preparing complex-shaped, ceramic-metal composite articles, comprising: (a) contacting a non-wettable powder that is non-wetting to a metal to be used for infiltration with a shaped ceramic body to form a layer of the non-wettable powder on one or more surfaces of the shaped ceramic body, wherein the shaped ceramic body has a region where there is no layer of the non-wettable powder, and (b) infiltration the shaped ceramic body with the metal through the region or regions where there is no layer of the non-wettable powder, such that a complex-shaped ceramic-metal composite comprising one or more metal phases and one or more ceramic phases is formed, wherein the article has substantially the net shape of the shaped ceramic body and undesirable regions of excess metal on the surface and undesirable phases within the complex-shaped ceramic-metal composite article near the surface are located only in the region or regions where there is no layer of the non-wettable powder. The process of the invention allows the preparation of complex-shaped ceramic-metal composite articles with undesirable regions of excess metal and undesirable phases on the surface(s), of, or within, the article only in the regions where there is, or was, no layer of non-wettable powder. The process of the invention allows the preparation of a complex-shaped ceramic-metal composite article which requires little or no machining of the surface(s) to achieve a finished article. A complex-shaped ceramic-metal composite article is prepared which contains few undesirable regions of excess metal and undesirable phases.