|
![]() |
![]() |
||||||||||||||||||||||||||||||||||||||||||||||
|
![]() |
![]() |
![]() |
||||||||||
|
![]() |
|
||||||||||
![]() |
![]() |
The Laboratory can perform Vickers microindentation hardness or microhardness tests using its Buehler Micromet II hardness testing machine. Any of the following test loads can be selected: 10, 25, 50, 100, 200, 500 and 1,000 gf. Microhardness testing is typically used to evaluate the success of surface hardening treatments to evaluate carburised, nitrided, carbonitrided, cyanided, flame hardened or induction hardened cases as well as detect and assess decarburisation. It can also test the hardness of individual phases in a microstructure, provided the phase is sufficiently large to accommodate the indent and this can help identify a metallurgical phase too. Microhardness testing is also useful to determine the hardness of specimens too small for traditional bulk indentation testing.
Even a slight level of decarburisation can be the cause of failure in some components. In high strength bolts used in cyclic loading decarburisation, typically caused during heat treatment, can facilitate the initiation of fatigue cracking leading.
The following two photomicrographs show for brass and steel of how the Vickers hardness of individual phases within polished metallurgical microstructures can be tested using microindentations to confirm the phase identity supplementing the metallographic identification.
|
![]() |
|
Copyright 2023 LPD Lab Services Ltd. All rights reserved. | ![]() |