Development and Evaluation of Integrity Assessment Tests for Polymeric Hermetic Seals

Abstract

An instrumented burst tester was developed that is capable of determining the precise internal pressure level at which a polytray package develops a small leak or explosively bursts. The total cost of fabricating a burst tester is approximately $5,000. Burst test results correlated well with peel strengths. It was found that non-defective seals from Vendors I and 3 performed very similarly. Defective polytray seals (entrapped matter, blisters, etc.) from Vendor I showed a large decrease in seal strength, while polytrays from Vendor 3 with short seal and entrapped matter defects showed no decrease in seal strength compared to non-defective seals. Finite element modeling showed that an internal pressure burst test adequately stresses the seal in all three possible crack propagation modes and another test to specifically test the seal in shear is not necessary. The non-contact ultrasonic inspection methods studied (airborne and laser-based) were either too slow or too insensitive to be feasible for 10O% online inspection of polytrays. The heat seal failure path always migrated to polyester/nylon bond in quad layer lid film before final failure of the seal.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Feb 19, 2006
Accession Number
ADA468015

Entities

People

  • Kevin Kit

Tags

Communities of Interest

  • Ground and Sea Platforms

DTIC Thesaurus Topics

  • Air Flow
  • Air Pressure
  • Birds
  • Data Acquisition
  • Failure Mode And Effect Analysis
  • Films
  • Finite Element Analysis
  • Internal Pressure
  • Manufacturing
  • Materials
  • Measurement
  • Pressure Gages
  • Pressurization
  • Test And Evaluation
  • Test Methods
  • Two Dimensional
  • Ultrasonic Inspection

Readers

  • Computer Programming and Software Development.
  • Mechanical Engineering/Mechanics of Materials.
  • Thermal Physics or Thermal Science.

Technology Areas

  • Directed Energy