1. The nitriding layer thickness
Nitriding layer includes compound layer and diffusion layer, nitriding layer thickness and time a parabola relationship. Metallographic method measuring nitriding layer thickness and hardness method.
(1) metallurgical method
The metallographic specimen abraded, after reagent (compound with 2-4% nitric acid alcohol solution, the diffusion layer with 5% solution of picric acid alcohol) after corrosion, measured with metallographic microscope magnification of 100-100 times, from the surface to the measurement and substrate have obvious boundaries, its length is the nitriding layer thickness.
(2) hardness method
With 100 g load vertical dozen of vickers hardness tester from the surface to the core hardness, hit 30-50 hv hardness is higher than the matrix, the distance from the surface area as the nitriding layer thickness.
2. The nitriding layer hardness
Surface hardness of nitrided case with 5-10 kg load vickers hardness tester measuring, carbonitriding layer thickness of 0.2 mm or less, the load should not be more than 5 kg. Surface hardness of the compound layer with 50-200 - g load measuring microhardness meter.
3. The nitriding layer brittleness
With a 10 kg load vickers hardness tester nitriding surface of specimen, in creasing the complete degree evaluation of brittleness.