采用Zn/Fe及Zn/Fe-Mn固固扩散偶方法,研究了锰对金属间化合物生长动力学的影响.对扩散偶在385℃扩散10～300min的研究结果表明,在Zn/Fe扩散偶中,扩散层以δ相为主,ζ相和δ相之间具有平直的界面,随扩散时间的延长,δ相的厚度增加,ζ相逐渐被消耗,厚度比dζ/dδ的值逐渐减小;在Zn/Fe-Mn扩散偶中,扩散层也以δ相为主,ζ相和δ相之间的界面更平直,铁基体中的锰在扩散初期促进δ相的生长,但在扩散后期促进ζ相生长.对Zn/Fe-Mn扩散偶中金属间化合物的生长动力学研究表明,0.4％(质量分数,下同)的锰使扩散层总厚度增加,当锰含量增加到1.2％以上时,扩散层总厚度反而开始下降.Zn/Fe、Zn/Fe-0.4％Mn、Zn/Fe-1.2％Mn及Zn/Fe-2.0％Mn四个扩散偶中总扩散层的生长均由扩散控制.%The growth of Zn-Fe intermetallic compounds and the effect of Mn were studied by means of diffusion experiments at 385℃ for 10—300min. The results show that the layer is mainly composed of δ phase in Zn/Fe couples, the interface between ζ and δ is planar, the thickness of δ phase increases and ζ phase decreases with prolongation of time, the value of dζ/dδ also decreases with time. In Zn/Fe-Mn couples, the diffusion layer is mainly composed of δ phase, the interface between ζ and δ is more planar, and the manganese in iron promotes the growth of δ phase in the initial period but the growth of ζ is promoted in the later period. The results of Zn/Fe-Mn couples show that 0. 4% manganese makes the total thickness of diffusion layer increase, however, when the manganese content increases to 1. 2%, the total thickness decreases. The growth of the total layer in four couples Zn/Fe,Zn/Fe-0. 45/oMn, Zn/Fe-1.2% Mn and Zn/Fe-2. 0%Mn are diffusion-controlled.
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