【摘要】 应用固体与分子经验电子理论(EET)对含铝的α-Fe、奥氏体、马氏体的价电子结构参数进行了计算与分析,进而研究了合金元素铝对合金钢行为和性能的影响。结果表明:铝固溶于α-Fe后,含铝结构单元α-Fe-Al最强键的键强nA和键能EA都高于α-Fe的结构单元的nA、EA值(增大25%),从而强化α-Fe,并使A3点提高;铝溶入奥氏体后,导致主键络的nA、EA值的减小(约15%),从而降低了过冷奥氏体的稳定性,提高了Ms点,减少淬火钢中残余奥氏体的含量;马氏体、奥氏体中的铝削弱了C原子与Fe等金属原子间的键合力,提高了碳的活度,其结果有助于高速钢中碳化物的弥散析出等效果。更多还原

【Abstract】 By means of the empirical electron theory of solids and molecules（EET）,the valence electron structures of α-Fe,austenite and martensite all containing aluminium in alloy steel were calculated and analysed,and its effects on behavior and properties of alloy steels were also studied.The results show that the bond strength n_A and the bond energy E_Aof the strongest bond in α-Fe-Al structural unit are higher（about 25%） than that in α-Fe structural unit when aluminium is dissolved into α-Fe,so strengthening α-Fe and elevating A₃ temperature.Once aluminium atoms enter into austenite,it leads to the decrease（about 15%） in the n_A and E_Avalues of the main bond network in γ-Fe-C-Al structural unit,and thus the austenite goes less stable,the M_s point of the alloy steel goes up,and the amounts of the retained austenite becomes lower.The interatomic bonding forces between C and Fe of α-Fe-C-Al structural units in martensite and γ-Fe-C-Al structural units in austenite are all weakened by element aluminium among them, carbon atoms in steels become more active,which is of benefits of the homogeneously dispersed precipitation of carbides and higher hot-hardness in high-speed steels.更多还原