There is provided a honeycomb structure where a crack at honeycomb segments, which constitute a honeycomb bonded assembly, is reduced. A honeycomb structure has a pillar-shaped honeycomb bonded assembly that has a plurality of pillar-shaped honeycomb segments having a porous partition wall defining a plurality of cells extending from an inflow end face as one end face to an outflow end face as another end face and becoming channels for a fluid, and a bonding layer bonding side surfaces of the plurality of honeycomb segments, and in the honeycomb bonded assembly, at 25 to 800 C., a thermal expansion coefficient of the bonding layer is larger than a thermal expansion coefficient of the honeycomb segment.

There is provided a honeycomb structure where a crack at a honeycomb substrate is reduced. A honeycomb structure has a honeycomb substrate that has a porous partition wall defining a plurality of cells extending from an inflow end face as one end face to an outflow end face as another end face and becoming channels for a fluid, and an outer circumference coating layer disposed at an outer circumference of the honeycomb substrate. At 25 to 800 C., a thermal expansion coefficient of the outer circumference coating layer is larger than a thermal expansion coefficient of the honeycomb substrate. The thermal expansion coefficients of the outer circumference coating layer and the thermal expansion coefficient at 25 to 800 C. preferably meet a relationship represented by the expression: 1.1<(the thermal expansion coefficient of the outer circumference coating layer/the thermal expansion coefficient of the honeycomb substrate)<40.

A method for forming an optical window. In one example, the method includes depositing a layer of eutectic bonding material onto a first surface of a first section of window material, positioning a second surface of a second section of window material onto the layer of eutectic bonding material such that the first surface is disposed opposite the second surface, and heating the eutectic bonding material to a temperature above a eutectic temperature of the eutectic bonding material and below a melting temperature of the window material for a predetermined length of time to form an optical window. The window material of the first section and the second section may be transparent to infrared radiation and comprise aluminum.

An example method includes introducing a slurry comprising particles in a joint region between a first substrate including graphite and a second substrate including mullite. The particles include an ytterbium disilicate compound. The method may further include heating an assembly including the first substrate, the second substrate, and the slurry to form a joint between the first substrate and the second substrate.

A method for forming a high temperature coating includes depositing a coating mixture on at least one ceramic substrate. The coating mixture includes rare earth disilicate particles and cordierite particles dispersed in a carrier medium. A weight ratio of the rare earth disilicate particles to the cordierite particles is in a range from about 50:1 to about 20:1. The method further includes heating the coating mixture above a sintering temperature of the cordierite particles to form the high temperature coating. The high temperature coating comprises the rare earth disilicate particles dispersed in a eutectic amorphous phase formed from the cordierite particles and the rare earth disilicate.

A corrosion-resistant component configured for use with a semiconductor processing reactor, the corrosion-resistant component comprising: a) a ceramic insulating substrate; and, b) a white corrosion-resistant non-porous outer layer associated with the ceramic insulating substrate, the white corrosion-resistant non-porous outer layer having a thickness of at least 50 m, a porosity of at most 1%, and a composition comprising at least 15% by weight of a rare earth compound based on total weight of the corrosion-resistant non-porous layer; and, c) an L* value of at least 90 as measured on a planar surface of the white corrosion-resistant non-porous outer layer. Methods of making are also disclosed.