Mechanical 1-2

“Standard Test Methods for Tension Testing of Metallic Materials” E8/E8M-11, ASTM International (2008).

  • ASTM standard (E8) used for tension testing guidance, with tests in constant displacement mode
  • 2 tests were performed: at room temperature and at 650 °C
  • Post-mortem metallography was performed on both samples

Room-Temperature Tensile Test

Mechanical 3

Room-Temperature Metallography

Mechanical 4

  • Voids were observed in bond lines away from fracture surface.
  • Unclear if voids were caused or exaggerated by EDM process or solely from tension tests.
  • Most bonds showed no change from as-made conditions.
  • Bond #7 (lower left) has no observed porosity. May indicate defects observed in corner sample are local to the corner region.

650 °C Temperature Tensile Test

Mechanical 5-6

650 °C Test Metallography

Mechanical 7
  • Results were effectively identical to room-temperature tests.
  • Voids were observed in bond lines away from fracture surface.
  • Most bonds showed no change from as-made conditions.

Mechanical Properties

Mechanical 8

  • Reduction in UTS was observed, as expected, between high- and low-temperature tests.
  • UTSmin of 485 MPa (ASME BPVC);
    • Room-temperature test failed ~72% of this value
    • 650 °C test failed ~52% of this value