Technical appendix at a glance
Diagrams of HAWAMID PA 12G
Vicat-B-50
Three materials in direct comparison: POM softens already at 60°C and then gradually becomes softer. PA 6 is the last to soften, but therefore deforms much earlier (see also elastic modulus). PA 12G remains solid and elastic up to 150°C.
Elastic modulus
PA 12G has the most evenly shaped curve: at -50°C PA 12G exhibits no „brittling“ and at 120°C no „softening“. PA 12G is elastic across a wide range of temperatures and exhibits good resilience.
Compressive stress / temperature
Even at ambient temperatures as low as 23°C the permissible compression stress of PA 12G is 43% or rather 31% higher than with OPM or PA 6. If the temperature rises, the application limits are soon reached with POM and PA 6. PA 12G, however, exhibits good elastic recovery and low creep behaviour across a wide range of temperatures.
Tensile test
PA 12G has a tensile strength of up to 66 N/mm². In isolated conditions at 23°C and under the exclusion of moisture PA 6 and POM obtain higher values – but only then! As soon as heat or moisture come into play POM and PA 6 quickly lose their strength.
Tensile stress / load period
Direct comparison of cast and extruded polyamides – i.e. comparison of polyamides with high and low crystallinity: The high-crystalline, cast PA 12G can be subjected to considerably higher and longer loads than the low-crystalline, extruded polyamides PA 12E and 6E.
Tensile stress / elongation
Based on the elastic modulus values the elongation curve representing the tensile stress of POM should be approx. 25% higher – i.e. despite high elasticity in the elastic modulus PA 12G exhibits a high resistance against deformation.
Tensile strength / relative humidity
The sum of all influencing factors determines the choice of the material: If dampness – or even humidity – is to be expected, PA 6 and PA 6.6 quickly lose their tensile strength.
Tensile strength / moinsture content in material
Here the special properties become particularly clear: PA 12G is the least water-absorbent polyamide and thus also exhibits constant and reliable physical properties even in wet environments.
Elongation / water absorption
The low water absorption of PA 12G also means high dimensional ssliderility. PA 6 and POM swell up considerably more and thus lose their dimensional ssliderility, which in turn causes more wear.
Moisture absorption / rel. humidity
Owing to its high moisture absorption, PA 6 exhibits lower strength and, due to its swelling behaviour, lower dimensional ssliderility. In the case of frost, there is also the risk of bursting. PA 12G is saturated at 1.1% – this means lasting dimensional ssliderility and strength even in damp environments and at temperatures as low as -50°C.