TWI Industrial Member Report Summary 383/1988
G E Hale
The realisation that plastics can be used as engineering materials has resulted in their increased application in higher integrity structural components. Allied to this, there is an increasing demand to join these materials; which for thermoplastics includes welding. However, further use of welded joints may be hampered by the non-availability of reliable procedures to assess the mechanical properties and to characterise the fracture behaviour of welds in plastics. In this report, conventional tensile and Charpy V notch impact toughness tests for plastics have been applied to hot plate welds in thermoplastics. The suitability of such tests for assessing welded plastics has been evaluated. Finally, linear elastic fracture mechanics has been used to characterise the fracture toughness of a number of thermoplastics, and experimental procedures which could form the basis of a standard have been examined.