Plastics materials testing expands

Tag : melt flow index

Testers will carry out static, creep, pendulum impact, drop impact,and high speed tests, as well as extrusion and hardness testers andHDT/Vicat machines.
Helmut Fahrenholz, who heads the competence center, is expectingthe plastics market to continue its strong development, he said:"The particular material characteristics, numerous designpossibilities, and cost-effective processing continually allow newproduct innovations which are not possible using other materials".
"Material characterisation plays an important role in development as well as quality assurance .
Examples of promising markets are the construction industry,electronics, automotive, packaging, and medical technology".
* Determination of the Melt Index Value - the Mflow (Modular Flow)is a plastometer which in its basic version covers all tests inaccordance with process A (MFR determination) of the ISO and ASTM standards.
By adding a displacement sensor, the Mflow can be upgraded tomeasure the MFR in accordance with process B.
An optional weight lift unit allows the machine to be operatedentirely automatically.
A significant advantage of the machine is the constant temperaturein the extrusion barrel, which meets the requirements of the draftISO/CD 1133-2 standard (moisture sensitive and time-dependentmaterials).
The Adaptive Parameter Configuration (APC) system is a uniqueinnovation which enables the tester to automatically select test parameters to optimise measurement precision.
The automatic detection and elimination of the effects of airbubbles in the material guarantees reliable and meaningful results.
* Determining MFR - the Cflow is based on the Mflow concept, but isdesigned solely for the simple determination of the MFR.
It is designed to be cost effective but cannot be upgraded to thesame degree as the Mflow.
The temperature control system meets the high requirements of the current draft for ISO/CD1133-2.
An automatic cutting unit for the extrudate improves the precisionwhen measuring higher MFR values, and a laboratory scale isrequired to calculate the result.
* Pendulum impact tester developments - Zwick introduced its HITseries of pendulum impact testers in 2005 and 2006 with impactenergy ranges of 5.5J, 25J, and 50J.
A new compact 5J ISO machine with an extremely compact constructionhas been developed for Charpy and impact tensile testing.
This is achieved by using short ISO pendulum hammers andrestricting the measurement range.
The tester possesses the same advantages as the larger machines,and uses the low-vibration, double-rod carbon pendulum, whichfeatures very high rigidity in the impact direction and a highconcentration of the mass at the point of impact.
The automatic pendulum recognition (APR) system means that the test results are traceable even if different pendulums are used.
Additional advantages are the slip-proof tool fixtures withdovetail guides and a convenient USB interface for connecting tothe testXpert II software.
The larger pendulum impact testers were also improved and Zwick hasadded a new motorised pendulum lifting unit together with a newCE-conforming protective shielding.
This increases the operating convenience significantly especiallyfor the large 25J or 50J pendulum hammers.
In addition, the motorisation is an important precondition for theautomation of the impact tests.
* Drop impact tester - Zwick recently introduced its new HIT230Finstrumented drop impact tester for multi-axis penetration testsand compression-after-impact tests.
This machine is optimised especially for the requirements ofpenetration tests, e g, in accordance with ISO6603-2 and ASTMD3763.
The drop impact tester is equipped with a low-noise characteristicpiezo force sensor.
The sensor is located very close to the impact point to minimisethe effects of the mechanical vibrations found in otherinstruments.
An innovative pneumatic specimen gripping system allows theinsertion and impacting of specimens in less than 5s.
In many applications it is possible to avoid the installation of anexpensive temperature chamber.
The testing area is outside of the protective shielding and iseasily accessible by the operator - but still optimally secured.
An optional spring pre-load is available for additionalacceleration to increase the impact speed.
The drop impact tester can also be used to initiate mechanicaldamage to long fiber-reinforced composites for thecompression-after-impact (CAI) test.
Additional tooling is available for this purpose.
The compression test for determining the influence of the damage onthe compressive strength is then performed on a static testingmachine.