Calculator for Exploring Relations Among the Elastic Constants
 Elastic Constant Converter
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 Calculator Introduction For isotropic materials, only two independent elastic constants are needed for describing the stress-strain relationship, i.e., Hooke's Law. This calculator computes the inter-relations among the 5 commonly used elastic constants:
 Symbol Name Other Names E Youngs modulus Elastic modulus, tension modulus n Poisson ratio G or m Shear modulus Rigidity modulus, 2nd Lamé constant K Bulk modulus Compression modulus l 1st Lamé constant
Select 2 constants for input, and calculate the rest.

 E: Young's Modulus nu: Poisson's Ratio G: Shear Modulus K: Bulk Modulus lambda: Lamé's constant E: Young's Modulus nu: Poisson's Ratio G: Shear Modulus K: Bulk Modulus lambda: Lamé's constant Units for modulii (E, G, K, l) Pa kPa MPa GPa psi ksi

 Young's Modulus E: 70.00 GPa Poisson's Ratio n: 0.30 Shear Modulus G: 26.92 GPa Bulk Modulus K: 58.33 GPa Lamé's Constant l: 40.38 GPa

Table of Relations among Elastic Constants
The relationships amongst the 5 elastic constants are shown in the table below.

 InputConstants Output Relations E = n = G = K = l = E, n - - E, G - - E, K - - E, l - - n, G - - n, K - - n, l - - G, K - - G, l - - K, l - -

For the case of {E, l} input, the factor R is defined as,

The 2nd Law of Thermodynamics requires that the following limits hold on the elastic constants,

E, G, and K > 0