(1. 華南理工大學(xué) 廣東省金屬新材料制備與成形重點(diǎn)實(shí)驗(yàn)室，廣州 510641；
2. 西南技術(shù)工程研究所，重慶400039)
摘 要: 采用XRD、SEM、TEM、萬能試驗(yàn)機(jī)、振動(dòng)樣品磁強(qiáng)計(jì)，系統(tǒng)研究了TiC含量對Fe43Ni35Co22中熵合金微觀組織、力學(xué)性能以及磁性能的影響。添加5%和10%(摩爾分?jǐn)?shù))Ti至中熵合金Fe43Ni35Co22，通過原位自生反應(yīng)形成TiC/Fe43Ni35Co22合金塊體，制備方法為“機(jī)械合金化(MA)+放電等離子燒結(jié)(SPS)”。結(jié)果表明：經(jīng)40 h球磨后, Fe43Ni35Co22粉末相的組成為FCC主相+少量BCC，兩種TiC/Fe43Ni35Co22粉末的相組成為BCC主相+FCC相。經(jīng)SPS燒結(jié)后，F(xiàn)e43Ni35Co22塊體為單相FCC和少量的雜質(zhì)；兩種TiC/Fe43Ni35Co22塊體均由FCC+TiC兩相組成，其中FCC相呈現(xiàn)“微米晶+超細(xì)晶”構(gòu)成的多尺度結(jié)構(gòu)，且隨著TiC含量的增加，超細(xì)晶區(qū)增多。性能上，TiC的添加大幅提高了Fe43Ni35Co22的壓縮屈服強(qiáng)度和矯頑力，同時(shí)也導(dǎo)致了材料的塑性和飽和磁化強(qiáng)度的降低。Ti添加量為5%的TiC/Fe43Ni35Co22綜合性能最優(yōu)異，其壓縮屈服強(qiáng)度為1352 MPa，壓縮斷裂應(yīng)變?yōu)?4.5%，矯頑力為992 A/m，飽和磁化強(qiáng)度為0.1387 A？m2/g。
關(guān)鍵字: 中熵合金；機(jī)械合金化；放電等離子燒結(jié)；力學(xué)性能；軟磁性能
（1. Guangdong Key Laboratory for Advanced Metallic Materials Processing, South China University of Technology, Guangzhou 510641, China;
2. Southwest Institute of Technology and Engineering, Chongqing 400039, China）
Abstract:The influence of TiC on the microstructure, mechanical and magnetic properties of Fe43Ni35Co22 medium-entropy alloy (MEA) were investigated using XRD, SEM, TEM, universal testing machine and VSM systematically. Adding 5% or 10% (mole fraction) Ti to the Fe43Ni35Co22 MEA, the bulk TiC/Fe43Ni35Co22 composite was achieved via in-situ reaction, using the combination of mechanical alloying (MA) and spark plasma sintering (SPS). The results show that after 40 h of ball milling, Fe43Ni35Co22 MEA powder is composed of a major face-centered cubic (FCC) phase and a small amount of body-centered cubic (BCC) phase, and the two TiC/Fe43Ni35Co22 powders are composed of a primary BCC phase and an FCC phase. Following by SPS, the bulk Fe43Ni35Co22 MEA show a single FCC phase with a small amount of contamination, and the two bulk TiC/Fe43Ni35Co22 consisted of a primary FCC phase with some TiC. The FCC phase in the two bulk TiC/Fe43Ni35Co22 exhibits a multi-scale structure consisting of micron grains and ultra-fine grains. In addition, the volume fractions of ultra-fine grains increase as the TiC increasing. In terms of properties, the addition of TiC evidently improves the compressive yield strength and coercivity of Fe43Ni35Co22, there by leading to a decrease in the plasticity and magnetic saturation of the material simultaneously. The bulk TiC/Fe43Ni35Co22 with 5% Ti addition show the best performance, in detail, showing a compressive yield strength of 1352 MPa and a compressive fracture strain of 24.5%, along with a coercivity of 992 A/m and a saturation magnetization of 0.1387 A？m2/g.
Key words: medium-entropy alloys; mechanical alloying; spark plasma sintering; mechanical property; soft magnetic property
