The present invention relates to parts of transparent corundum ceramics and the production and use of said parts.

The present invention relates to parts of transparent corundum ceramics and the production and use of said parts.

A die or piston of a spark plasma sintering apparatus, wherein the die or piston is made from graphite and the outer surfaces of the die or piston are coated with a silicon carbide layer with a thickness of 1 to 10 micrometres, the silicon carbide layer being further optionally coated with one or more other layer(s) made from a carbide other than silicon carbide chosen from hafnium carbide, tantalum carbide and titanium carbide, the other layer(s) each having a thickness of 1 to 10 micrometres. A spark plasma sintering (SPS) apparatus comprising the die and two of the pistons, defining a sintering, densification or assembly chamber capable of receiving a powder to be sintered, a part to be densified, or parts to be assembled. A method of sintering a powder, densifying a part, or assembling two parts by means of a method of spark plasma sintering (SPS) in an oxidising atmosphere, using the spark plasma sintering (SPS) apparatus.

A die or piston of a spark plasma sintering apparatus, wherein the die or piston is made from graphite and the outer surfaces of the die or piston are coated with a silicon carbide layer with a thickness of 1 to 10 micrometres, the silicon carbide layer being further optionally coated with one or more other layer(s) made from a carbide other than silicon carbide chosen from hafnium carbide, tantalum carbide and titanium carbide, the other layer(s) each having a thickness of 1 to 10 micrometres. A spark plasma sintering (SPS) apparatus comprising the die and two of the pistons, defining a sintering, densification or assembly chamber capable of receiving a powder to be sintered, a part to be densified, or parts to be assembled. A method of sintering a powder, densifying a part, or assembling two parts by means of a method of spark plasma sintering (SPS) in an oxidising atmosphere, using the spark plasma sintering (SPS) apparatus.

A method of manufacturing ceramic tape includes a step of directing a tape of partially-sintered ceramic into a furnace. The tape is partially-sintered such that grains of the ceramic are fused to one another yet the tape still includes at least 10% porosity by volume, where the porosity refers to volume of the tape unoccupied by the ceramic. The method further includes steps of conveying the tape through the furnace and further sintering the tape as the tape is conveyed through the furnace. The porosity of the tape decreases during the further sintering step.

A method of manufacturing ceramic tape includes a step of directing a tape of partially-sintered ceramic into a furnace. The tape is partially-sintered such that grains of the ceramic are fused to one another yet the tape still includes at least 10% porosity by volume, where the porosity refers to volume of the tape unoccupied by the ceramic. The method further includes steps of conveying the tape through the furnace and further sintering the tape as the tape is conveyed through the furnace. The porosity of the tape decreases during the further sintering step.

An aluminium oxide ceramic material containing the following components:

TABLE-US-00001 component wt.-% Al.sub.2O.sub.3  95.0 to 99.989 MgO 0.001 to 0.1 Eu, calculated as Eu.sub.2O.sub.3  0.01 to 1.0.

A break resistant sapphire plate and a corresponding production process. The sapphire plate may include a planar sapphire substrate, and at least one shock absorbing layer arranged on a surface of the substrate. The shock absorbing layer may have a thickness of between 0.1% to 10% of the thickness of the substrate. The production process for producing the sapphire plate may include providing a planar sapphire substrate, and coating at least one surface of the substrate with a shock absorbing layer. The shock absorbing layer may include a layer thickness between 0.1% to 10% of the thickness of the substrate.

A break resistant sapphire plate and a corresponding production process. The sapphire plate may include a planar sapphire substrate, and at least one shock absorbing layer arranged on a surface of the substrate. The shock absorbing layer may have a thickness of between 0.1% to 10% of the thickness of the substrate. The production process for producing the sapphire plate may include providing a planar sapphire substrate, and coating at least one surface of the substrate with a shock absorbing layer. The shock absorbing layer may include a layer thickness between 0.1% to 10% of the thickness of the substrate.

A break resistant sapphire plate and a corresponding production process. The sapphire plate may include a planar sapphire substrate, and at least one shock absorbing layer arranged on a surface of the substrate. The shock absorbing layer may have a thickness of between 0.1% to 10% of the thickness of the substrate. The production process for producing the sapphire plate may include providing a planar sapphire substrate, and coating at least one surface of the substrate with a shock absorbing layer. The shock absorbing layer may include a layer thickness between 0.1% to 10% of the thickness of the substrate.