Kinetics of Thermally Induced Porosity Expansion in Hot Isostatic Pressing
Thermally induced porosity expansion occurs when trapped argon exerts internal pressure exceeding matrix creep strength during high-temperature thermal exposure.
ASTM E1447
Meaning
Standard laboratory procedures published by the American Society for Testing and Materials define the chemical analysis of refractory alloys. Quality inspectors use astm e1447 to measure hydrogen concentration in titanium materials. The measurement utilizes an inert gas fusion furnace equipped with thermal conductivity detectors.
The methodology is restricted to metal samples that can be melted in a graphite crucible.
Analytical Technique
Thermal energy melts the specimen in an inert atmosphere to release trapped gases. For astm e1447, a high-purity argon or helium carrier gas transports the extracted hydrogen to the detection system. The instrument measures the change in thermal conductivity or uses infrared detection to calculate the gas weight percentage.
Precise calibration against certified reference materials ensures the output remains accurate.
Sourcing Criterion
Low hydrogen content prevents hydrogen embrittlement in structural battery housings. Titanium sheets verified by astm e1447 guarantee that incoming metal batches meet safety specifications. Correct assessment reduces risk of spontaneous fractures.
Operating Boundary
The procedure ceases to yield reliable data when the specimen has excessive surface contamination. Under astm e1447, sample preparation must eliminate cutting fluids or oxide layers that alter the measurement. Handlers must use clean forceps and wash the metal pieces in acetone before testing.
Incorrect handling introduces atmospheric moisture, which artificially inflates the hydrogen readings.