Ultrahigh-strengthened intragranularκ-Al_(2)O_(3)nanoparticles dispersed Mo composite prepared via SPS sintering of core-shell Mo nanocomposite powder  

作　　者：Shu-Xin Yan Ming-Yang Li Xiao-Bo He Fu-Fa Wu Shun-Hua Chen Guo-Dong Sun 

机构地区：[1]Xi’an Rare Metal Materials Institute Co.Ltd,Xi’an 710016,China [2]School of Materials Science and Engineering,Liaoning University of Technology,Jinzhou 121001,China [3]School of Mechanical Engineering,Hefei University of Technology,Hefei 230009,China

出　　处：《Journal of Materials Science & Technology》2024年第34期32-43,共12页材料科学技术(英文版)

基　　金：supported by the Natural Science Foundation of Shaanxi Province,China(No.2020JC-50);the National Natural Science Foundation of China(Nos.52304386 and 52203382);the Young Talent Fund of Association for Science and Technology in Shaanxi,China(No.2021-1-2);the Key Research and Development Program of Shaanxi(No.2024GX-YBXM-355);the Innovation Ca-pacity Support Projects of Shaanxi Province(No.2023KJXX-096).

摘　　要：Oxide dispersion strengthening(ODS)is an effective method to improve the mechanical properties of Mo-based materials.However,the mechanical properties of traditional ODS-Mo composites are always lim-ited by the coarsening and intergranular distribution of second-phase particles.In this work,an effective nano-reinforcement dispersion strategy was developed to fabricate an ODS-Mo composite with ultrafine grain and intragranular distribution of second-phase particles.Core-shell structural Mo nanocomposite powders,with internally distributed sub-10 nm Al_(2)O_(3)dispersoids,were prepared by nano atomization doping(AD)followed by a chemical vapor transport growth strategy.Then,ODS-Mo composites with ultra-fine Mo grain(below 700 nm)and high-density intragranularκ-Al_(2)O_(3)(below 20 nm)nanoparti-cles were prepared via spark plasma sintering(SPS),in which a coherent interface betweenκ-Al_(2)O_(3)and Mo matrix was formed.The composites present remarkably improved hardness(above 500 HV),bend strength,and compressive yield strength(above 1664 MPa)at room temperature,with a suitable strain to fracture of 27.1%.The calculation of strengthening mechanisms indicates that the enhancement was mainly attributed to the intragranularκ-Al_(2)O_(3)nanoparticles.This nano-sized reinforcement distributed within the grain can more effectively pin dislocations and achieve dispersion strengthening in ODS-Mo composites.Therefore,this strategy can efficiently construct intragranular second-phase nanoparticles and open up new avenues to fabricate high-performance ODS-Mo composites.

关 键 词：Oxide dispersion strengthened NANOCOMPOSITE Spark plasma sintering Refractory metals 

分 类 号：TB3[一般工业技术—材料科学与工程]