Are rectangular block springs available in market?

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Rectangular block springs, resembling mechanical keys, are not commonly available in the market, particularly in metal. The discussion highlights that while elastomers can achieve low stiffness values, their nonlinear stress-strain characteristics and the Poisson effect complicate their use as linear springs. Flat springs exist, but the design in question resembles a non-linear 'square rubber mount.' The conversation also references alternative spring designs, such as zigzag or magazine springs, and coil springs. Overall, the specific rectangular block spring design remains elusive in current applications.
k.udhay
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TL;DR
Spring design - Rectangular block springs
Dear all,

I am interested to know if there is any spring available which is just a rectangular block - Looks more like a mechanical key. Preferrably made of metal. The dimensions / numbers shown in the following image are indicative:
1733928316214.png


Pl. let me know if you have come across some applications similar to this. TIA.
 
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Start with some basic calculations. The equation for column stiffness is ##k = AE/L##, where:
##k## = spring stiffness
##A## = cross sectional area
##E## = material modulus of elasticity
##L## = length (height) of the column

The only unknown is the material modulus, so solving for that results in a modulus of 20 MPa. That's four orders of magnitude less stiff than metals. Elastomers are available with modulus in that range, however there are two things to be aware of:

1) Elastomers have nonlinear stress-strain characteristics.
2) Even if the material has a linear stress-strain curve, the load deflection curve of a solid block is nonlinear. As the block is compressed, it squishes outward due to the Poisson effect, which increases the cross sectional area, which steepens the load deflection curve.
 
Flat springs are a thing, but your drawing looks more like a 'square rubber mount'. And those are (intentionally!) not linear.
 
k.udhay said:
Pl. let me know if you have come across some applications similar to this. TIA.
A zigzag, or "magazine spring", made from a strip of flat steel.
Google images 'gun magazine springs'

Five coil springs, each 10 mm diameter, arranged in a row.

One thin walled, spring steel tube. 50 mm long by say 8 mm diameter.
 
leaf spring
 

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