Understanding Plastic Material Properties in Analyzing and Preventing Product Failures

Course Number: AP5222
Date: 05/14/2013 - 05/16/2013
Time: 8:00 AM - 4:00 PM
Location: Akron Polymer Training Center, Akron, OH 44325-5404
Cost: $1,800 USD
CEU's: 2.25
Instructor: Mr. Mike Sepe

Course Overview

The ability of a plastic component to function properly for its expected life is dependent upon an accurate assessment of the application requirements and the ability to align those requirements with a material that has the appropriate properties. The design of the part, the material selected to make it, and a sound approach to processing the material, all play a crucial role in determining the life of the product. When parts do fail, a systematic process must be undertaken to arrive at a root cause and solutions should address this root cause in order to be successful over the long term.

Understanding the interaction between design, material properties, and the manufacturing process is made more difficult by the fact that available material properties are typically inadequate in capturing long-term performance considerations. This course will combine an in-depth understanding of plastic material behavior at the fundamental level with the techniques and tools that are used to diagnose, correct, and prevent product failures. It will illustrate the shortcomings in the industry’s current methods of evaluating plastic material properties and provide alternatives that give the in-depth understanding needed to design and produce parts that perform to requirements.

Course Outline

1. Elements of a Successful Plastic Product
2. Principles of Plastic Part Design
   • Nominal Walls
   • Ribs and Other Projections
   • Holes and Other Depressions
   • Designing for Manufacturing (DFM)
   • Design Properties versus Inherent Properties of Materials
3. Material Properties
   • Defining the Application Environment - Time, Temperature, Stresses, etc.
   • Amorphous and Semi-crystalline Polymers
   • The Importance of Molecular Weight
   • Structural Choices Within a Polymer Family
   • Property Modifiers and Additives
   • Regulatory Considerations - UL, NSF, FDA
   • Performance and Processability
   • Establishing the Cost/Performance Balance
4. Failure Analysis Tools
   • Material Testing - Composition and Degradation
     • Molecular Weight Evaluations
     • Thermal Analysis - DSC, TGA, DMA, TMA
     • Spectroscopy - FTIR, EDS, XPS, SIMS
   • Microscopy - Cross Sections and Scanning Electron Microscopy
   • Physical Property Evaluation – Your Part Is Not a Tensile Bar
   • FEA and Its Relation to the Application Environment
   • Advanced Characterization of Mechanical Properties
5. Property Evaluations - Short-term
   • Tensile, Flexural, and Compressive Properties
   • Impact properties - Various Methods of Measurement
   • Thermal Properties
   • Other Properties - Chemical Resistance, Optical, Radiation Resistance
   • Why the Data Sheet Properties Do Not Work for Material Selection
   • The Real Behavior Behind the Numbers
   • The Role of Material Property Databases in Selection
6. Property Evaluations - Long-term
   • Effects of Temperature
     • Reduction in Mechanical Properties at Elevated Temperatures
     • Dimensional Stability
     • Structural Changes Due To Thermal Aging
     • Thermal Degradation and Oxidation
     • Loss of Ductility at Reduced Temperatures
   • Chemical Resistance – Effects of Temperature and Time
   • Creep Resistance, Stress Relaxation, and Fatigue
     • Defining the Mechanisms
     • Data Presentation
     • Accelerated Testing Methods - Advantages and Pitfalls
   • The Fundamental Equivalence of Temperature and Time
   • Environmental Stress Crack Resistance - Differences from Chemical Attack
7. Details of Performing an Effective FEA to Ensure Good Field Performance