Contact us

Call us: (800) 667-3220 

Email us: info@ADMET.com

Ask an Engineer form

Request a quote form

Receive an email when a new article is posted

Your email:

About ADMET

  • Founded by engineers in 1989.
  • Offers advanced materials and product testing systems that are reliable and easy to use.
  • Willing to modify our systems to meet your needs.
  • On-site service and calibration team includes over 100 individuals in over 40 locations.
  • On-site and web based training.
  • Unlimited phone and email support.

Authors

Richard Gedney, Founder

Orick Kelley, Sales Engineer for metals, concrete, etc...

Debbi Cohen, Sales Engineer, medical materials and finished device testing applications

Andrew DeWolfe, Sales Engineer for plastics, foam, textiles, etc... 

Current Articles | RSS Feed RSS Feed

ASTM D 882 Tensile Strength Properties of Thin Plastic Film

  | Share on Twitter Twitter | Submit to Digg digg it |  Add to delicious  delicious |  Submit to StumbleUpon StumbleUpon |  Share on LinkedIn LinkedIn | Submit to Reddit reddit 

One of the most common specifications that our customers follow is ASTM D882 which is the Standard Test Method for Tensile Properties of Thin Plastic Sheeting. This test is very similar to the common ASTM D638 test whereby plastic material is pulled until in breaks in order to measure elongation, tensile modulus, tensile yield strength, and tensile strength at break. However, it is designed specifically for thin sheeting and film less than 1 mm (0.04") thick.

.

  

The nice part about ASTM D 882 is that the specimens are strips of film that are 1" wide by 6" long and are not "dumbbell" or "dog bone" shaped. The flat geometry of the specimens and the typical characteristic of films having high elongation allow most users to avoid using an extensometer which allows them to reduce the cost of the testing system and simplifies their testing regimen.

The two main things to keep in mind in regards to equipment are the height of the testing machine and having grips designed to hold the thin film correctly. We always recommend our eXpert 7601single column test machine with 29" of crosshead travel for films with less than 300% elongation and our 53" model for really high elongation films that elongate up to 900%. The grips we recommend are pneumatic vise grips with rubber coated inserts. The rubber coated inserts help to keep the film from prematurely breaking at the grip edge, and in combination with the constant pneumatic pressure the film is prevented from slipping out of the grips during the test. We use foot pedals to allow the operator to open and close the grips with their feet because thin films usually require both hands to line everything up properly. If you have a 30" crosshead travel machine, the grips and load cell will take up about 12" of that travel, and the material being tested will take up another 4" (gage length). This leaves 14" of testing travel which will be fine for materials with less than 350% elongation (14" crosshead travel / 4" original gage length = 3.5 * 100% = 350%) A 54" crosshead travel machine is better suited for materials that have elongation up to 950%

 

We are always available to answer your questions. Should you have any questions, please feel free to call us @ 800-667-3220 or visit our website for more information.

   

 eXpert 7601              Pneumatic Vise Grip               Foot Pedal


All Posts