未知题型
碳在γ-Fe中扩散，D0=2．0×10-1cm2／s，Q=140×103J／mol，求碳在γ-Fe中927℃时的扩散系数，并计算为了得到与927℃渗碳10h相同的结果，在870℃渗碳需要多长时间?
- A.0×10-1cm2／s，Q=140×103J／mol，求碳在γ-Fe中927℃时的扩散系数，并计算为了得到与927℃渗碳10h相同的结果，在870℃渗碳需要多长时间?
【参考答案】
×
D927℃=1．61×10-7cm2／s,需要20．1h。
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