Provided is a ceramic sintered body having high wear resistance and chipping resistance. Also provided are an insert, a cutting tool and a friction stir welding tool, each of which uses such a high-performance ceramic sintered body. The ceramic sintered body includes Al.sub.2O.sub.3 (alumina), WC (tungsten carbide) and ZrO.sub.2 (zirconia), wherein Zr (zirconium) element is present at either one or both of: (1) a grain boundary between crystal grains of the Al.sub.2O.sub.3; and (2) a grain boundary of crystal grains of the Al.sub.2O and crystal grains of the WC, wherein the ceramic sintered body contains 55.0 to 97.5 vol % of the WC, 0.1 to 18.0 vol % of the ZrO.sub.2, and the balance being the Al.sub.2O.sub.3, and wherein the ZrO.sub.2 is in a phase of tetragonal structure (T) or a mixed phase of tetragonal structure (T) and monoclinic structure (M).

A method of providing a self-healing coating includes providing substrate, applying a layer of an aluminum-containing MAX phase material and another material to the substrate. The method includes exposing the layer to a temperature greater than 2000 F. to form alpha aluminum.

A method of providing a self-healing coating includes providing substrate, applying a layer of an aluminum-containing MAX phase material and another material to the substrate. The method includes exposing the layer to a temperature greater than 2000 F. to form alpha aluminum.

Precision glass molds are described, which are formed by coating a mold made from high purity, fme grain sized graphite, with a coating including titanium. In various implementations, the titanium coating is overcoated with yttria (Y.sub.2O.sub.3) to provide a high precision glass mold of superior performance character. The resultant glass molds can be used to form glass articles having a highly smooth finish, for high precision applications such as consumer electronic device applications, medical instruments, and optical devices. The use of high purity, fme grain size graphite allows molds to be machined at low cost, thereby eliminating the need to fabricate a metal mold that must be coated with multiple layers including metal diffusion barrier layers to meet operational requirements for such precision applications.

Precision glass molds are described, which are formed by coating a mold made from high purity, fme grain sized graphite, with a coating including titanium. In various implementations, the titanium coating is overcoated with yttria (Y.sub.2O.sub.3) to provide a high precision glass mold of superior performance character. The resultant glass molds can be used to form glass articles having a highly smooth finish, for high precision applications such as consumer electronic device applications, medical instruments, and optical devices. The use of high purity, fme grain size graphite allows molds to be machined at low cost, thereby eliminating the need to fabricate a metal mold that must be coated with multiple layers including metal diffusion barrier layers to meet operational requirements for such precision applications.

A coating for an article includes a seal coat comprising self-healing particles disposed in a seal coat matrix and a bond coat disposed on the seal coat. The bond coat includes a matrix, diffusive particles disposed in the matrix, and gettering particles disposed in the matrix. A coating for an article and a method of applying a coating to an article are also disclosed.

A high temperature article includes a carbon/carbon (C/C) composite substrate and a hybrid coating on the C/C composite substrate. The hybrid coating includes a high temperature antioxidant layer on a surface of the C/C composite substrate and a low temperature sealant on a surface of the high temperature antioxidant layer. The low temperature sealant is formed from a glass-forming soluble salt.

A high temperature article includes a carbon/carbon (C/C) composite substrate and a hybrid coating on the C/C composite substrate. The hybrid coating includes a high temperature antioxidant layer on a surface of the C/C composite substrate and a low temperature sealant on a surface of the high temperature antioxidant layer. The low temperature sealant is formed from a glass-forming soluble salt.

Described are molds that include a ceramic material at a surface, as well as methods of forming the molds, and methods of using the molds; the ceramic material is constituted substantially, mostly, or entirely of three elemental components designated M, A, and X; the M component is at least one transition metal; the A component is one or a combination of Si, Al, Ge, Pb, Sn, Ga, P, S, In, As, Tl, and Cd; and the X component is carbon, nitrogen, or a combination thereof.

Described are molds that include a ceramic material at a surface, as well as methods of forming the molds, and methods of using the molds; the ceramic material is constituted substantially, mostly, or entirely of three elemental components designated M, A, and X; the M component is at least one transition metal; the A component is one or a combination of Si, Al, Ge, Pb, Sn, Ga, P, S, In, As, Tl, and Cd; and the X component is carbon, nitrogen, or a combination thereof.