Methods of making a honeycomb structure

A method of making a honeycomb structure comprising the steps of:

• providing a honeycomb body including a first end face and a second end face, the honeycomb body comprising a material having a first effective dielectric constant ∈h expressed with a first real part R1 and a first imaginary part I1;
• providing a first extension and a second extension along a longitudinal axis of the honeycomb body, wherein the first extension is positioned with respect to the first end face and the second extension is positioned with respect to the second end face, wherein the first and second extensions each include a second dielectric constant ∈e expressed with a second real part R2 and a second imaginary part I2;
• and
• exposing the honeycomb body and the extensions to microwaves to dry the honeycomb body,
• wherein a real ratio R is defined as R1 divided by R2 prior to the step of drying, an imaginary ratio I is defined as I1 divided by I2 prior to the step of drying, and 3.7≦R1≦30.2, 0.15≦I1≦3.6, 0.16≦R≦6 and 0.1≦I≦10000.

A method of making a honeycomb structure comprising the steps of:

• providing honeycomb body including a first end portion including a first end face and a second end portion including a second end face, wherein the honeycomb body includes a ceramic and/or ceramic-forming material having a material composition configured such that, when the honeycomb body is heated in an isolated manner through exposure to microwaves, drying efficiency is below a predetermined value at the first end portion and the second end portion of the honeycomb body;
• providing a first extension and a second extension along a longitudinal axis of the honeycomb body, wherein the first extension is positioned with respect to the first end face and the second extension is positioned with respect to the second end face;
• and
• exposing the honeycomb body and the extensions to microwaves to dry the honeycomb body,
• wherein drying efficiency that is below the predetermined value is confined to the first extension and the second extension.