ASTM D2304-18
Standard Test Method for Thermal Endurance of Rigid Electrical Insulating Materials

Standard No.

ASTM D2304-18

Release Date

2018

Published By

American Society for Testing and Materials (ASTM)

Status

Be replaced

Replace By

ASTM D2304-23

Latest

ASTM D2304-23

Scope

1.1 This test method2 provides procedures for evaluating the thermal endurance of rigid electrical insulating materials. Dielectric strength, flexural strength, or water absorption are determined at room temperature after aging for increasing periods of time in air at selected-elevated temperatures. A thermal-endurance graph is plotted using a selected end point at each aging temperature. A means is described for determining a temperature index by extrapolation of the thermal endurance graph to a selected time. 1.2 This test method is most applicable to rigid electrical insulation such as supports, spacers, voltage barriers, coil forms, terminal boards, circuit boards and enclosures for many types of application where retention of the selected property after heat aging is important. 1.3 When dielectric strength is used as the aging criterion, it is also acceptable to use this test method for some thin sheet (flexible) materials, which become rigid with thermal aging, but is not intended to replace Test Method D1830 for those materials which must retain a degree of flexibility in use. 1.4 This test method is not applicable to ceramics, glass, or similar inorganic materials. 1.5 The values stated in metric units are to be regarded as standard. Other units (in parentheses) are provided for information. 1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. A specific warning statement is given in 11.3.4. 1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

ASTM D2304-18 Referenced Document

• ASTM D149 Standard Test Method for Dielectric Breakdown Voltage and Dielectric Strength of Solid Electrical Insulating Materials at Commercial Power Frequencies
• ASTM D1830 Standard Test Method for Thermal Endurance of Flexible Sheet Materials Used for Electrical Insulation by the Curved Electrode Method
• ASTM D229 Standard Test Methods for Rigid Sheet and Plate Materials Used for Electrical Insulation
• ASTM D5423 Standard Specification for Forced-Convection Laboratory Ovens for Evaluation of Electrical Insulation
• ASTM D570 Standard Test Method for Water Absorption of Plastics*， 2018-08-01 Update
• ASTM D790 Standard Test Methods for Flexural Properties of Unreinforced and Reinforced Plastics and Electrical Insulating Materials*， 2024-04-21 Update

ASTM D2304-18 history

• 2023 ASTM D2304-23 Standard Test Method for Thermal Endurance of Rigid Electrical Insulating Materials
• 2018 ASTM D2304-18 Standard Test Method for Thermal Endurance of Rigid Electrical Insulating Materials
• 2010 ASTM D2304-10 Standard Test Method for Thermal Endurance of Rigid Electrical Insulating Materials
• 1997 ASTM D2304-97(2002) Standard Test Method for Thermal Endurance of Rigid Electrical Insulating Materials
• 1997 ASTM D2304-97 Standard Test Method for Thermal Endurance of Rigid Electrical Insulating Materials