Vickers Hardness Tester

The Vickers hardness tester measures hardness by pressing a diamond indenter shaped as a square pyramid into a material's surface under a known load and measuring the diagonal length of the resulting indentation to calculate a hardness value. Engineers at the British armaments and engineering firm Vickers Ltd, principally Robert L. Smith and George E. Sandland, developed the test in 1921 as an improvement on the existing Brinell method, seeking a single hardness scale that could cover the full range from very soft to very hard materials using one small, geometrically similar indenter regardless of load. Because the pyramidal indentation is always geometrically similar at any load, the Vickers test avoids the load-dependent inconsistency of the ball-indenter Brinell method and is widely used for testing thin sheets, coatings and small precision parts.