(西安科技大學(xué) 材料學(xué)院，西安 710054)
摘 要: 以TiC、TiN、Ni、Co等粉末為主要原料，以稀土Y2O3為添加劑，采用無壓燒結(jié)技術(shù)制備Ti(C,N)基金屬陶瓷，研究燒結(jié)工藝和稀土Y2O3添加量對(duì)Ti(C,N)基金屬陶瓷顯微組織和力學(xué)性能的影響。結(jié)果表明：隨著溫度的升高，TiC、TiN、WC、Cr3C2、Mo等相逐漸消失，向硬質(zhì)芯相擴(kuò)散發(fā)生固溶，經(jīng)溶解-析出過程，最終形成新的Ti(C,N)硬質(zhì)相和(Cr,W,Mo,Ti)(C,N)固溶體環(huán)形相，黏結(jié)金屬Ni和Co主要以Ni相、TiCo和Co3W3C中間相的形式存在；稀土Y2O3的添加未改變Ti(C,N)基金屬陶瓷燒結(jié)過程中的相結(jié)構(gòu)演變過程，材料的顯微硬度、抗彎強(qiáng)度和斷裂韌性均隨Y2O3添加量的增加呈先增加后降低的趨勢(shì)，當(dāng)Y2O3的加入量為0.8%(質(zhì)量分?jǐn)?shù))時(shí)，Ti(C,N)基金屬陶瓷的力學(xué)性能最佳，樣品的顯微硬度、抗彎強(qiáng)度和斷裂韌性相比1450 ℃燒結(jié)50 min樣品的分別提高了7.9%、45.8%和6.1%。
關(guān)鍵字: Ti(C,N)基金屬陶瓷；Y2O3；燒結(jié)工藝；力學(xué)性能
（College of Materials Science and Engineering, Xi’an University of Science and Technology, Xi’an 710054, China）
Abstract:Ti(C,N)-based cermets were prepared by pressureless sintering method using TiC, TiN, Ni and Co powders as main raw materials and Y2O3 as additive. The effects of sintering process and Y2O3 content on the microstructure and mechanical properties of Ti(C,N)-based cermet were investigated. The results show that TiC, TiN, WC, Cr3C2 and Mo phases disappear gradually and diffuse into hard and rim phases by dissolution-precipitation process with increasing the sintering temperature, finally, new Ti(C,N) hard phases and (Cr,W,Mo,Ti)(C,N) rim phases are formed, while the bonding metals Ni and Co exist mainly in the form of Ni phases and the intermediate phases of TiCo and Co3W3C. The phase structure evolution of Ti(C,N)-based cermet almost has no change with adding Y2O3 during sintering process. The micro-hardness, bending strength and fracture toughness of Ti(C,N)-based cermet increase first, and then decrease with the increase of Y2O3 content. Ti(C,N)-based cermet achieves the best mechanical properties with 0.8% Y2O3 (mass fraction) addition, the micro-hardness, flexural strength and fracture toughness are increased by 7.9%, 45.8% and 6.1%, respectively, when compared to those of the sample sintered at 1450 ℃ for 50 min.
Key words: Ti(C,N)-based cermet; Y2O3; sintering process; mechanical property
