氮化物弥散强化铁基合金的显微组织和力学性能研究  

Microstructure and mechanical properties of nitride dispersion strengthened ferrite-based alloy

作　　者：郭旸[1] 刘祖铭[1] 苏鹏飞[1] 麻梦梅 段然曦 王帅[1] Guo Yang Liu Zuming Su Pengfei Ma Mengmei Duan Ranxi Wang Shuai(State Key Lab of Powder Metallurgy, Central South University, 410083)

机构地区：[1]中南大学粉末冶金国家重点实验室,长沙410083

出　　处：《粉末冶金技术》2016年第5期361-367,共7页Powder Metallurgy Technology

基　　金：国家高技术研究发展计划(863计划)项目(2009AA032526);国家自然科学基金项目(50634060)

摘　　要：本实验向雾化Fe-12.8Cr-3.4W铁基粉末中引入氮化物粉末进行球磨,然后对球磨粉末进行热挤压和热轧制制备得到合金样品。对雾化粉末和球磨粉末的形貌和成分、各组成形合金的显微组织、各组成形合金的力学性能以及断口形貌进行了研究。实验结果表明,球磨对粉末晶粒起到了细化作用,同时球磨后粉末与空气接触会引入少量的氧,YN(氮化钇)的引入起到了细化球磨粉末的作用;在氮化物弥散强化合金中检测到了尺寸小于100 nm的Ti N和TiO_2的复合弥散颗粒,少量弥散颗粒与合金中的Cr、W、Y和O元素结合长大形成大于100 nm的复杂化合物颗粒。采用氮化钇制备的合金抗拉强度与氧化钇合金基本相同,延伸率增加,同时显微硬度提高;采用氮化钛和氮化钇进行制备的合金显微硬度进一步增加。Nitride powders were introduced into Fe-12. 8Cr-3. 4W ferrite-based alloy powders during the procedure of ball milling,then ball-milled powders were molded by hot extrusion and hot rolling in sequence to produce samples.Morphology and element content of ball-milled powders,microstructure of alloy samples,mechanical properties of alloy samples and fracture morphology of alloy samples were investigated. The results show that ball milling procedure refine grain size of powder and cause microscale introduction of oxygen in powders with contact of air; introduction of YN resulte in smaller ball-milled powders Dispersed compound particles of TiN and TiO_2 smaller than 100 nm are observed and a little amount of these particles coarsen because of comnbination with Cr,W,Y and O. Alloy with the addition of yttrium nitride has nearly equal tensile properties with ODS steel and has higher elongation rate as well as microhardness. The addition of yttrium nitride and titanium nitride result in further increase of microhardness.

关 键 词：弥散强化 机械合金化 抗拉强度 显微硬度 

分 类 号：TG132.32[一般工业技术—材料科学与工程]