(1. 中南大學(xué) 粉末冶金國(guó)家重點(diǎn)實(shí)驗(yàn)室， 長(zhǎng)沙 410083;
2. 西南應(yīng)用磁學(xué)研究所， 綿陽(yáng) 621000)
摘 要: 研究了Sn，Al，Dy等元素對(duì)燒結(jié)釹鐵硼合金熱處理行為的影響。發(fā)現(xiàn)Dy和Al的影響很小，含Dy和Al的釹鐵硼合金，其熱處理行為與三元釹鐵硼類似；而Sn對(duì)該合金的熱處理行為有重大影響。添加少量Sn(約0.1%)就能使合金熱處理溫度范圍變寬，且獲得最佳性能的熱處理溫度移向高溫。但是含Sn合金在525～625 ℃回火，矯頑力反而比回火前低。X射線衍射發(fā)現(xiàn)，這樣的合金有明顯的α-Fe衍射峰出現(xiàn)。實(shí)驗(yàn)表明，僅用晶粒表面光滑化不足以解釋合金的熱處理行為，還應(yīng)考慮亞穩(wěn)相轉(zhuǎn)變對(duì)熱處理行為的影響。在優(yōu)化熱處理工藝條件下，制得(BH)max=223.7 kJ/m3,Hci＞2.11 MA/m的Nd27Dy6Fe65.35Al0.4B1.1Sn0.15合金。
關(guān)鍵字: 錫； NdFeB磁體； 熱處理
JING An-jin2, ZHANG Ming2, CHEN Biao2
（1. State Key Laboratory for Powder Metallurgy,
Central South University, Changsha 410083, P.R.China;
2. Southwestern Institute of Applied Magnetics,
Mianyang 621000, P.R.China）
Abstract:Effects of Sn, Dy and Al on annealing of NdFeB alloys were investigated. It is found that anneal temperatures are not sensitive to doping Dy or Al. However, Sn influences the annealing of alloys intensely. The temperature range of annealing is broadened by m, inor amount of Sn(about 0.1%), and the best annealing is moved to higher temperature. In addition, after annealing at 520～625 ℃, coercivities of alloys doped with Sn are lowered. When alloy is checked by X-ray diffraction, there is α-Fe peak for the alloy degraded coercivity. It is showed by experiment that the smoothing of grain surface is not enough to explain the performance of annealing. The transformation of additional ferromagnetic phases must be responsible for it, too. After optimizing processing, Nd27Dy6Fe65.35Al0.4B1.1Sn0.15 magnet gains excellent properties, (BH)max=223.7kJ/m3, and Hci＞ 2.11 MA/m.
Key words: tin; NdFeB magnet; heat treatment
