There are two factors which affect the blades cutting performance; the metal it is made from and its thickness.
The metal has to be hard enough to retain its sharp cutting edge for a reasonable time yet flexible enough to avoid it being brittle. The material of choice is a high carbon steel called SK2 – this is a Japanese standard steel specially made for the job.
The thickness of the blade has an effect on how much it will flex when it is being used. Flexible blades are not really a good thing since they make it more difficult to cut in a straight line – as a rule the thicker the better.
C.K and Avit blades have a blade thickness of 0.6mm which is the thickest available.
Whilst being made from the same SK2 steel, segmented blades are slightly thinner (0.5mm) so that they can be snapped off to reveal a new sharp section.
This makes them more flexible than trapezoidal blades, however, the blade handle on high quality products such as the C.K range will have a blade clamp that helps keep the blade rigid in use.