โ Scribed by D.H. Lassila; H.K. Birnbaum
No coin nor oath required. For personal study only.
Hydrogen charged nickel was deformed in tension at a test temperature of 208 K to study the diffusive segregation of hydrogen during straining and the dependence of embrittlement on grain boundary hydrogen concentration and deformation rate. Tests were performed on samples in the as-quenched condition at various strain rates. An increase in the degree of embrittlement at slow strain rates can be attributed to diffusive segregation of hydrogen to grain boundaries during the test period. The embrittlement of samples with equal grain boundary hydrogen concentration was found to be relatively insensitive to strain rate, bulk hydrogen concentration and the total time at the test temperature.
R&un&-Du nickel charge en hydrogene a et& dtformt en traction a 290 K pour ttudier la segregation par diffusion de l'hydrogdne pendant la deformation, ainsi que l'influence de la concentration en hydrogene dans les joints de grains et de la vi&se de deformation sur la fragilisation. Ces essais ont ete realists sur des echantillons bruts de trempe pour differentes vitesses de deformation. On peut attribuer l'augmentation du taux de fragilisation observee aux faibles vitesses de deformation a la segregation par diffusion de l'hydrogine vers les joints de grains pendant l'essai. Pour des khantillons de mime concentration en hydrogbne aux joints de grains, la fragilisation est relativement insensible a la vitesse de deformation, a la concentration globale en hydrogbne et au temps total passe a la temperature de l'essai.
Zusammenfassung-Wasserstoffbeladenes Nickel wurde im Zugversuch bei 208 K verformt. urn die Segregation des Wasserstoffs durch Diffusion wlhrend der Dehnung und die Abhlngigkeit der Versprodung von der Wasserstoffkonzentration an den Komgrenzen und von der Verformungsrate zu bestimmen. Die Versuche wurden an abgeschreckten Proben mit verschiedenen Verformungsgeschwindigkeiten durchgefilhrt. Eine Zunahme der Verspriidung bei kleinen Verformungsgeschwindigkeiten kann der diffusiven Segregation des Wasserstoffs an den Komgrenzen wahrend der Versuchsperiode zugeschrieben werden. Die Versprijdung von Proben, die vergleichbare Wasserstoffkonzentration an den Korngrenzen aufweisen, hing wenig von der Verformungsrate, der Wasserstoffkonzentrationen im Volumen und der gesamten Zeit bei der Versuchstemperatur ab.
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