Janka-Hardness
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Janka-Hardness | What is the Janka Hardness?The Janka hardness is a method for determining the hardness of wood, indicating how resistant the material is to indentations. It measures the amount of force required to press a steel ball with a diameter of 11.28 mm halfway into the wood. The required force, measured in kilonewtons (kN), provides information on the wood's resistance to pressure marks. The higher the Janka value, the harder and more resistant the wood.
Illustration janka hardness test | Photo © by Hugo Kämpf The Janka Hardness TestIn the Janka hardness test, the steel ball is evenly pressed into the wood until half the ball diameter is embedded. The test provides comparable values that reflect the hardness of various wood types. For example, oak, with a Janka value of about 6 to 7 kN, is significantly harder than softwoods like pine. Extremely hard tropical woods, such as ipe or bongossi, can reach values over 12 kN. This test is especially relevant for wood used in high-wear areas, such as flooring or furniture. The higher the Janka hardness value, the less prone the wood is to scratches and dents in everyday use.
Janka Hardness vs. Brinell HardnessIn addition to the Janka hardness, there is also the Brinell hardness, a similar method often used for metals but also applicable to wood. Unlike the Janka hardness, where the ball is pressed only halfway, the Brinell test measures the indentation depth of the entire ball and calculates the hardness value based on the size of the resulting impression. Both tests provide helpful information about material resistance, with the Janka test specifically developed for wood and the Brinell test more broadly applied to metals and other materials.
Verschiedene Holzarten nach der Janka-Härte sortiert
In Summary - Explained SimplyThe Janka hardness measures how resistant wood is to pressure marks, while the Brinell hardness is a more general test for indentation resistance. Both methods help assess material hardness, especially for high-stress areas like flooring or furniture.
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