Efficiency of Information on Hardness Measurements of Thermoplastics

In the present study results of penetration depth measurements as a function of (loading) time using an automated test appliance are given for 10 thermoplastics. The specimens' temperatures were varied at several stages between room temperature and 100 deg C. At each stage time-dependent hardness curves H(t) have been derived. The findings permit a more efficient classification of the material's behaviour than is possible with conventional hardness testing (so-called "one-point-measurement"). So the concept of hardness curves H(t) ought to be taken into consideration on the occasion of future revision of hardness test standards. 18 ref.--AA