Official Answer
Answer
Yes, and disproportionately so. For a wave spring, load at a given deflection varies with the cube of the flat wire thickness — increase thickness by 20 % and load rises by roughly 70 %. The catch is that thickness drives operating stress at the same time, so a thicker spring reaches its stress limit sooner and its fatigue life shortens, and it raises solid height, so it may no longer fit the cavity it was meant to solve. In practice thickness is the last variable a designer should change. Waves per turn and number of turns are adjusted first, because they move load and rate without the same penalty.
