Barcol Impressor
Portable Hardness Tester
Technical Specifications

The Impressor is best suited for testing homogeneous materials. Materials of granular, fibrous or coarse structure will produce a wide variation in hardness readings because of the small diameter of the indenter point.

For accurate readings, material should be at least 1 /32" thick and large enough for a minimum distance of 1/8" in any direction from the indenter point to the edge of the specimen. The testing area should be smooth and free from mechanical damage.

Simply exert alight pressure against the instrument to drive the spring-loaded indenter point into the material. The indenter point must be perpendicular to the surface being tested. On very soft metals, the highest reading should be used since cold flow permits the spring loaded indenter point to continue penetration.

Note: Physical characteristics of very soft materials are such that uniform correlation between different hardness measuring systems cannot be established. We recommend that Impressor hardness limits for each material be established by test.

Recommended Sample Sizes