(1. 南昌大学 材料科学与工程学院,南昌 330031;2. 南昌硬质合金有限责任公司,南昌 330013;3. 中南大学 粉末冶金国家重点实验室,长沙 410083)
摘 要: 研究在常规退火前的高温短时间预退火对非晶Fe86Zr7B6Cu1合金晶化过程的影响,通过分析温度对形核速率和晶粒长大速率的影响规律,讨论预退火对非晶Fe86Zr7B6Cu1合金晶化过程的影响机制。结果表明,合适的预退火引起纳米晶Fe86Zr7B6Cu1合金中结晶α-Fe相的晶粒尺寸的减小和体积分数的增加。非晶Fe86Zr7B6Cu1合金经600 ℃退火1 h后的结晶α-Fe相的晶粒尺寸和体积分数分别为13.2 nm和65.2%,而在750 ℃保温2 min再在600 ℃退火1 h后的结晶α-Fe相的晶粒尺寸和体积分数分别为9.5 nm和72.4%。 在750 ℃保温2 min再在600 ℃退火1 h后的试样比常规退火得到的试样具有更为优良的软磁性能。
关键字: Fe86Zr7B6Cu1合金;纳米材料;磁性材料;显微组织;非晶相;结晶
(1. School of Materials Science and Engineering, Nanchang University,Nanchang 330031, China;2. Nanchang Cemented Carbide Limited Liability Company,Nanchang 330013, China;3. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China)
Abstract:The effect of pre-annealing at higher temperature for short duration before conventional annealing at 600 ℃ for 1 h on the crystallization process of amorphous Fe86Zr7B6Cu1 alloy was studied. The affecting mechanism of pre-annealing on the crystallization process of amorphous Fe86Zr7B6Cu1 alloy is discussed by analyzing the temperature dependence of the nucleation rate and the grain growth rate. It is shown that proper pre-annealing leads to the decrease of the grain size and the increase of the volume fraction of crystalline α-Fe in nanocrystalline Fe86Zr7B6Cu1 alloy. BCC α-Fe with grain size of 9.5 nm and volume fraction of 72.4% is formed in ribbon after it has been pre-annealed at 750 ℃ for 2 min followed by conventional annealing at 600 ℃ for 1 h. The grain size and volume fraction of crystalline α-Fe in ribbon annealed at 600 ℃ for 1 h are 13.2 nm and 65.2%,respectively. Complex permeability spectra show that pre-annealing at 750 ℃ for 2 min before conventional annealing at 600 ℃ for 1 h results in a distinct improvement of soft magnetic properties.
Key words: Fe86Zr7B6Cu1 alloy; nanomaterial; magnetic material; microstructures; amorphous phase; crystallization