HYDROGEN DAMAGE IN HIGH PURITY IRON

Hydrogen damage in Fe of 99.99% purity has been investigated by Doppler broadening measurement. Experimental results show that when the iron is charged with hydrogen in 0.5 mol / L H_2SO_4 so-lution, the critical current density to cause hydrogen damage is 20 mA / cm~2. While a little As_2O_3, saying 250 mg / L, added to H_2SO_4 solution, even rather small current density, 0.2 mA / cm~2, would cause hydrogen damage. With the help of slow tensile test, it revealed that the hydrogen damage occurred in the specimen may be influential to the subsequent process of deformation and fracture.