Abstract
Studies on the equilibrium between austenitic iron and nitrogen under various conditions of the maximum pressure of 920 kg/cm2 and the temperature range of 950°∼1300°C were carried out using a high temperature-high pressure equipment. It was shown that the concentration of nitrogen in austenite deviates from Sieverts’ law with increasing pressure. The cause for such discrepancy was considered thermodynamically and statistically. That is, the experimental result can reasonably be explained from the geometrical consideration that the chemical potential of a nitrogen atom in austenite with a high nitrogen content, departs remarkably from the value for the ideal random interstitial solid solution, since each interstitial atom added excludes other interstitial atoms from the seven adjacent sites. Thus, the activity of nitrogen in austenitic iron can be expressed by the following equations:(This article is not displayable. Please see full text pdf.)
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
