Effect of Nb and Si Content on Phase Stability, Microstructure and Mechanical Properties of Sintered Ti–Nb–Si Alloys

• Published in: Metals (Basel ) Vol. 15; no. 1; p. 34
• Main Authors: Luup Carvalho, Derek Manoel, Paim, Deivison Daros, Schramm Deschamps, Isadora, Aguilar, Claudio, Klein, Aloísio Nelmo, Cavilha Neto, Francisco, Oliveira Neves, Guilherme, Binder, Cristiano
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.01.2025
• Subjects: Alloying elements; Beta phase; Biocompatibility; biomaterials; Cold pressing; Corrosion resistance; Design of experiments; elastic modulus; Energy consumption; Grains; Industrial development; Mechanical properties; Metal products; Niobium base alloys; Phase stability; Powder metallurgy; Powders; Precipitates; Precipitation heat treatment; Silicon; Sintering; Sintering (powder metallurgy); Specialty metals industry; Specific gravity; thermodynamics; Titanium; Titanium alloys; Titanium base alloys; Transplants & implants; Ultimate tensile strength; Wear resistance; Yield stress; Canada
• ISSN: 2075-4701; 2075-4701
• DOI: 10.3390/met15010034

The development of beta titanium alloys with biocompatible elements to replace Al and V is a subject of significant interest in the biomedical industry. This approach aims to enhance biocompatibility and mitigate potential cytotoxic effects associated with traditional alloying elements. In this work, Ti–xNb–ySi alloys were produced using powder metallurgy, with x of 35, 40, and 45 wt.%, and y of 0.10, 0.35, and 0.60% wt.%, using a 32 experimental design. Milling was used to mix and disperse the powders, followed by cold pressing, sintering, and heat treatment. Nb was the main element used to stabilize the β phase, and Si was used to form Si precipitates, although Si also exhibits a β-stabilizing effect. It was found that an increase from 0.10 to 0.35 wt.% of Si improved relative density, with no benefits observed at 0.60 wt.% Si. Electron microscopy showed the presence of β phase grains, and grains with β + α intragranular structures and precipitates. Increasing Nb content resulted in a decrease in ultimate tensile strength while increasing Si content from 0.10% to 0.35 wt.% exhibited the opposite effect.