rubber stiffness compared to compression rubber stiffness compared to compression gascan328 (Mechanical) (OP) 4 Dec 14 15:17 This is just a generic question at this point and pardon my ignorance on the subject, "Does rubber stiffness change as it is compressed?" Thanks RE: rubber stiffness compared to compression cloa (Petroleum) 8 Dec 14 13:38 http://www.ce.tuiasi.ro/~bipcons/Archive/369.pdf This basically shows that it gets stiffer under isostatic (one direction) compression- more strain more stiffness. Its also history dependant. http://www.eng-tips.com/threadminder.cfm?pid=1529 Use translation assistance for Engineers forum Note the rules include No Student posting RE: rubber stiffness compared to compression stancom (Specifier/Regulator) 9 Dec 14 11:23 So much depends on whether the test piece or component is compressed under lubricated or bonded conditions, and in the latter case shape factor, ie the ratio of the area to which the force is applied to the force-free area, also comes into plsy. At small compressive deformations the relationship between stress and strain is approximately linear when the compessed surfaces are fully lubricated, so the compression modulus is constant. When the rubber is bonded to metal or another rigid substrate lateral movement is confined and the stress will rise disproportionately with the compressive strain. There is plenty on this subject on the web and I would also suggest looking through the test method ISO 7743: 2011, which gives a simple explanation of the facrors involved. Afraid I do not really follow cloa's argument, but the influence of strain history is correct. RE: rubber stiffness compared to compression gascan328 (Mechanical) (OP) 9 Dec 14 11:40 Thank you both for your input!