【摘要】 简要叙述了Nd Fe B合金在平衡、非平衡条件下的凝固规律及其晶体生长特点。高性能烧结Nd Fe B磁体对母合金组织的要求 (不含α Fe ,具有明显的柱状晶 ,柱状晶尺寸均匀 ,宽度在 5～ 2 5μm之间 ,富Nd相有序排列 ,分布均匀 )及Nd Fe B磁体在通讯、电子、医疗等行业的大量应用 ,促进了新兴近快冷厚带制备技术的诞生。系统阐述了新兴近快冷厚带制备技术的特点与优势 ;从柱状晶的生长条件出发 ,重点说明了诸如化学成分优化、氧含量、温度场、冷却速度等关键工艺参数的控制原则。更多还原

【Abstract】 The solidification processes of Nd-Fe-B alloys in equilibrium and non-equilibrium conditions and the growth characteristics of Nd-Fe-B crystals were introduced briefly. The sintered Nd-Fe-B magnets with high performances require the as cast alloys have such microstructures: no α-Fe, evident columnar crystals with 5～25 μm width and even size, rich Nd phases in ordered array. The requirements above and vast applications in communication, electronics, medical appliance and other fields promote the birth of new strip casting technology. The features and advantages are introduced generally. With a view to growth conditions of columnar crystals, the control principles of key parameters, such as chemical composition, content of oxygen, temperature field, cooling rate, etc. were discussed.更多还原