文章信息/Info

Title:

The influence of Cr doping on the flexural strength and microstructure of Sm2Co17 type sintered permanent magnet

作者:

李雨;  俞能君; 劉冰; 劉戀; 張林; 葛洪良

1中國計量大學 材料與化學學院，浙江 杭州 310018 2綿陽量大技術創新服務有限公司，四川 綿陽 621000

Author(s):

LI Yu; YU Nengjun;  LIU Bingyu;  LIU lian;  ZHANG Lin;  GE Hongliang

1.College of Materials and Chemistry, China Jiliang University, Hangzhou 310018, China 2.Mianyang Liangda Technology Innovation Service Co., Ltd,Mianyang 621000, China

關鍵詞:

Sm2Co17型燒結永磁體; Cr摻雜; 高抗彎強度; 顯微組織; 元素分布

Keywords:

Sm2Co17 type sintered permanent magnets; Cr doping; high flexural strength; microstructure; element distribution

文獻標志碼:

A

摘要:

Sm2Co17型燒結永磁體具有優異的磁性能、熱穩定性和耐腐蝕性，但由于其主相2:17R相晶體結構滑移系少、對稱性差等導致永磁體表現出較低的抗彎強度。本文研究了Cr元素添加對Sm(Co0.68Fe0.22Cu0.06Zr0.04)7.5燒結磁體微觀結構和抗彎強度的影響。研究發現，適量Cr添加可以有效提高Sm2Co17型燒結永磁體的抗彎強度，當添加量為2wt.%時，磁體的抗彎強度為180.12 MPa，較未添加Cr磁體提升了約47.75%。微結構和元素分布研究發現Cr元素在磁體中均勻分布，對磁體的相組成和斷裂機理基本沒有影響，但添加了Cr元素的磁體晶界處形成了細小而不規則晶粒，這種細小晶粒中的胞狀組織尺寸明顯小于未添加磁體，形成了類似細晶強化的效果，提高了磁體的抗彎強度。本研究提出了通過添加Cr元素誘導Sm2Co17型燒結磁體內部形成細小不規則晶粒及其內部的細小胞狀組織提升磁體抗彎強度的新方法，有助于優化釤鈷磁體性能提升。

Abstract:

The Sm?Co?? type sintered permanent magnets possess excellent magnetic properties, thermal stability, and corrosion resistance. However, due to the primary 2:17R phase crystal structure having few slip systems and poor symmetry, these permanent magnets exhibit relatively low bending strength. This study investigates the effects of Cr element addition on the microstructure and bending strength of Sm(Co?.??Fe?.??Cu?.??Zr?.??)?.? sintered magnets. The research found that an appropriate amount of Cr addition can effectively enhance the bending strength of the Sm?Co?? type sintered permanent magnets. When the Cr addition is 2 wt.%, the bending strength of the magnet reaches 180.12 MPa, an increase of approximately 47.75% compared to magnets without Cr addition. Microstructure and elemental distribution analysis revealed that the Cr element is uniformly distributed within the magnet, having no significant impact on the phase composition and fracture mechanism of the magnet. However, the magnets with Cr addition formed fine irregular grains at the grain boundaries, and the size of the cellular structures within these fine grains was significantly smaller than those in magnets without Cr addition. This resulted in a fine-grain strengthening effect, improving the bending strength of the magnets. This study proposes a new method to enhance the bending strength of Sm?Co??type sintered magnets by inducing the formation of fine irregular grains and their internal fine cellular structures through the addition of Cr element, which helps optimize the performance of samarium-cobalt magnets.