Processing and Microstructure of Hot-Press Sintered High-Nb-TiAl Alloys and Their Carbide-Reinforced Composites
WANG Huijun
YANG Ying
LI Juan
SUN Dingbang
CHEN Jiaying
LIANG Yongfeng
LIN Junpin
Abstract：This study systematically investigates the forming processes and microstructural evolution of high-Nb TiAl alloys and their carbide-reinforced composites.It focuses on analyzing the effects of ball-milled powder blending and hot-press sintering parameters on microstructure,while revealing the variation patterns of oxygen mass fraction during forming process.Results indicate that in the sintering temperature range of 1 350～1 450℃,the 1 425℃-30 MPa-20 min process yields a dense TiAl alloy with uniform fully lamellar microstructure.Ball milling represents the primary stage contributing to oxygen mass fraction increase.Glove box purging proves more effective than vacuum pump purging in reducing oxygen mass fraction.The high oxygen mass fraction(3.63%)in nano-TiC powder causes oxygen mass fraction in sintered specimens to increase proportionally with powder loading.Compared to the 150 r/min-8 h mixing process,the 200 r/min-8 h parameters significantly improve the dispersion uniformity of nano-TiC particles and suppress carbide agglomeration in TiAl-based composites by enhancing powder fragmentation and specific surface area.
Keywords：powder metallurgyTiAl alloyscomposite materialsprocess optimizationmicrostructure
Publication Date：2025-12-25
Online Publishing Date：2026-01-05(First online date of this platform, not the publication date of the document)
Pages：8( 1-8 )