Hard metal test ball
Carbide test ball: spherical indenter made of tungsten carbide for Brinell testing on hard metals. Avoids deformation of steel balls.
Physical-Chemical Mechanism of Action
A hard metal test ball is made of tungsten carbide, a very hard material that deforms minimally during Brinell testing. It presses into the surface of the metal being tested, forming an indentation. The size of this indentation is measured and used to estimate strength.
Metallurgical Relevance & Welding Risks
Using hard metal test balls is especially important for hard materials like steel or nickel alloys. It avoids the deformation of the ball itself, which can occur with older steel balls, leading to inaccurate readings. This directly impacts quality assurance and the reliability of the weld.
Workshop Practice & Instructions
Use hard metal test balls for Brinell tests on hard metals. Make sure the ball is clean and undamaged. Press it with a specified load (e.g., 1000 N) into the metal surface. Measure the diameter of the resulting indentation and calculate the Brinell hardness number using the formula HB = 2P / (π * D²), where P is the load and D is the diameter of the indentation.