N_2氣體中的H_2O及微量O_2對固體滲碳之作用

The influences of a Trace of O_2 in N_2 and H_2O in N_2 Atmospheres on Pack Carburizing of Steel

10.6623/chem.1976012

黃振賢(C. H. Hwang)；呂璞石(P. S. Lu)；吳錫侃(S. K. Wu)

化學

65年3期（1976 / 09 / 01）

72 - 84

繁體中文

爲要明瞭N_2氣體中所含的微量O_2對固體滲碳作用的影響，把商用瓶裝N_2氣體中所存在的O_2除掉，然後送入滲碳容器內實施固體滲碳。其次爲要明瞭各種成分比的N_2+H_2O混合氣體中實施純鐵之固體滲碳時，此等混合氣體的成分對滲碳作用的影響，先以純N_2氣體趕除滲碳管內及木炭裏面所吸含的原存氣體和水分，再以預定成分的N_2+H_2O混合氣體完全置換後，實施純鐵的滲碳。試驗所得的結果如下：(a)N_2氣體中所含的微量O_2對固體滲碳作用有很大的影響。(b)以木炭爲滲碳劑實施純鐵之固體滲碳時，雖然事先以純化過的純N_2氣體把滲碳容器內所存在的原存氣體及木炭裏面所吸含的空氣和水分趕除，但是純鐵仍能發生微量的滲碳。(c)在各種成分比之N_2+H_2O混合氣體中實施純鐵的固體滲碳時，隨著混合氣體中的H_2O量增加，滲碳量及滲碳層厚度都增加。但是當H_2O量達到9~10%時其滲碳量可達最高值，而不因H_2O量之再增加而增加其滲碳量。

In this paper, we intend to study the effect of a trace of O_2 in N_2 gas and various compositions of H_2O in N_2 gas mixture on pack carburizing. Before experiments, we purged the experimental container packed with charcoal by pure N_2 gas to remove air and moisture, then the container was equilibrated with a certain composition of N_2+H_2O mixture. The sample of electrolytic iron was carburized under this condition. The results are as follow: (a) The trace of O_2 contained in N_2 gas have a remarkable influence on pack carburizing at higher temperatures. (b) Under the atmosphere of a trace of H_2O in N_2 gas the amount of carbon content and depth of casburized layer were very small and thin, respectively. (c) The carbon content and depth of carburized layer increase with the increasing amount of H_2O in the system of Na_2+H_2O. (d) The carbon content and the depth of carburized layer reached the maximum value when the amount of H_2O raised up to 9-10% (by volume) in the system and kept constant value even when the amount of H_2O increased further.