Effect of nitrogen addition and aging treatment on microstructure and high temperature mechanical properties of Ti‐48Al‐2Cr‐2Nb (at%) intermetallic alloy

•N addition resulted in a significant microstructure refinement in 4822 alloy.•N addition prevented instability of the lamellar structure during aging.•Higher SPT forces were achieved in the N-bearing alloys aged at 700 °C/10 h.•N addition increased uniformity of microstructures and mechanical prope...

Full description

Saved in:
Bibliographic Details
Published in:Journal of alloys and compounds 2022-05, Vol.904, p.164077, Article 164077
Main Authors: Ghorbani, Hamid Reza, Kermanpur, Ahmad, Rezaeian, Ahmad, Sadeghi, Fazlollah, Ahmadi Siahboumi, Abbas
Format: Article
Language:English
Subjects:
Age hardening
Aging
Aging (metallurgy)
Alloys
Electric arc melting
Fracture mechanics
Fragmentation
High temperature
High temperature mechanical properties
Hot isostatic pressing
Intermetallic compounds
Lamella
Lamella fragmentation
Lamellar structure
Mechanical properties
Microstructure
Nitrogen
Small punch test
Solution annealing
Ti-48Al-2Cr-2 Nb intermetallic alloy
Titanium base alloys
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:•N addition resulted in a significant microstructure refinement in 4822 alloy.•N addition prevented instability of the lamellar structure during aging.•Higher SPT forces were achieved in the N-bearing alloys aged at 700 °C/10 h.•N addition increased uniformity of microstructures and mechanical properties.•The 1N alloy exhibited the most uniform deformation behavior during SPT. Effects of nitrogen (N) addition (0.5, 1, and 2 at%) on microstructure formation and high temperature mechanical properties of the age-hardened Ti‐48Al‐2Cr‐2Nb (4822, at%) intermetallic alloy were investigated. Alloys were fabricated by vacuum arc re-melting followed by hot isostatic pressing, solution annealing, and finally aging at two different conditions of 700 °C/10 h or 900 °C/1 h. Mechanical properties of the age-hardened samples were investigated via small punch testing at 800 °C. Results showed that N addition resulted in microstructure refinement and increased uniformity of microstructures and mechanical properties. Lamella coarsening and fragmentation was occurred during both aging conditions; however, a more stable lamellar microstructure was achieved by N addition. Colonies with various lamellar orientation showed different fragmentation behavior. Better mechanical properties was achieved in the alloy containing 1 at%N after aging at 900 °C/1 h. Inter-lamellar fracture was the predominant fracture mechanism in all intermetallic alloys.
ISSN:0925-8388
1873-4669
DOI:10.1016/j.jallcom.2022.164077