The rapid densification behavior of powder metallurgy Ti alloys by induction heating sintering  

作　　者：Kejia Pan Xiaotao Liu Bao Wang Shuai Gao Shixing Wu Ning Li 

机构地区：[1]State Key Laboratory of Materials Processing and Die&Mould Technology,School of Materials Science and Engineering,Huazhong University of Science and Technology,Wuhan 430074,China

出　　处：《Journal of Materials Science & Technology》2024年第14期152-164,共13页材料科学技术（英文版）

基　　金：supported by the National Key Research and Development Program of China(No.2020YFB2008300);the National Natural Science Foundation of China(Nos.51971097 and 52301147);the Young Elite Scientist Sponsorship Program by China Association for Science and Technology(No.YESS20210054);the Hubei Province Natural Science Foundation(No.ZRMS2022000863);the Fundamental Research Funds for the Central Universities of Huazhong University of Science and Technology(No.2172021XXJS010)and the project supported by State Key Laboratory of Powder Metallurgy,Central South University,Changsha,China.

摘　　要：Micropores are decisive to mechanical properties and thermal deformation capabilities of powder met-allurgy(P/M)Ti alloys sintered compacts.As a result,achieving express densification is of prime im-portance and has attracted increasing attention recently.Induction heating owns the merits of high effi-ciency,short process,and low cost,and thus has huge potential to be used as a sintering approach for the fabrication of P/M Ti alloys.Nevertheless,the facilitated densification behavior associated with induction heating sintering remains unclear so far.To address it,powder metallurgy Ti6Al4V is manufactured via induction heating sintering with which the underlying sintering mechanism is investigated in-depth.It is found that induction heating could generate a fully densified compact in a remarkably shortened time,demonstrating its superior sintering efficiency as compared with conventional resistance furnace heat-ing.COMSOL finite element analysis reveals that the maximum current density during induction heating can reach 10^(6)A m^(–2)though the magnetic field strength is solely 0.02 T,leading to a slight tempera-ture difference of approximately 30℃between the interior and exterior of the billet.Furthermore,the rapid heating essentially starts at sharp corners of particles due to the potent current concentration ef-fect,which facilitates the cracking of the particle surface oxide film and thus enhances the direct contact between them.Moreover,the electromigration effect caused by induction current promotes the diffusion capability of elements,giving rise to expedited densification,alloying,and chemical homogenization.This work provides not only critical insight into the sintering mechanism of induction heating sintering but also significant guidance for low-cost powder metallurgy materials preparation.

关 键 词：Titanium alloy Powder metallurgy Induction heating sintering Radiation heating sintering Current field SIMULATION 

分 类 号：TF125.2[冶金工程—粉末冶金]