Hardness measurements are used as a quality control check of the consistency of formulation and processing of brake linings. Gogan hardness is nondestructive (the penetrator causes shallow surface deformation.). Gogan hardness method alone does not show anything about a lining's ability to develop friction or to resist fade when used as a friction element in brakes.

The hardness and the range of hardness are peculiar to each formulation, thickness, and contour; therefore, the acceptable values and ranges must be established for each formulation and part configuration by the manufacturer.

The hardness of sintered powder metal lining is usually determined with Rockwell Superficial hardness equipment. See ASTM B 347.

Purpose

To measure the Gogan Hardness of Brake Linings

There are two accepted methods to measure hardness of brake linings:

Gogan hardness measurements measure the compression of the materials under load while, Rockwell hardness measurements measure the depth of penetration after the application of a load (See SAE J2654).

Selection between the two methods depends on the specific properties desired.

Customers who purchased SAE J379
also purchased

• AATCC 147 : Antibacterial Activity Assessment of Textile Materials: Parallel Streak Method
• API RP 941 : Steels for Hydrogen Service at Elevated Temperatures and Pressures in Petroleum Refineries and Petrochemical Plants-Seventh Edition
• ASME B31.3 : Process Piping-Includes Interpretation 22

See More Documents