The crack and pore formation mechanism of Ti–47Al–2Cr–2Nb alloy fabricated by selective laser melting

Shi, Xuezhi; Wang, Huaxue; Feng, Wei; Zhang, Yulian; Ma, Shuo; Wei, Jun

doi:10.1016/j.ijrmhm.2020.105247

Cited by 45 publications

(13 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, high cooling rates typical for laser-based powder bed fusion and directed energy deposition AM techniques lead to high residual stresses, which makes it difficult to produce crack-free intermetallic parts. Shi X. et al [13] showed that it is not possible to produce crack-free Ti-47Al-2Cr-2Nb alloy samples by the laser powder bed fusion (L-PBF) using 200 • C preheating. The L-PBF of Ti-48Al-2Cr-2Nb alloy with 450 • C preheating resulted in severe cracking formation, indicating that higher preheating temperatures must be utilized [14].…”

Section: Introductionmentioning

confidence: 99%

Additive Manufacturing of Ti-48Al-2Cr-2Nb Alloy Using Gas Atomized and Mechanically Alloyed Plasma Spheroidized Powders

et al. 2020

View full text Add to dashboard Cite

In this paper, laser powder-bed fusion (L-PBF) additive manufacturing (AM) with a high-temperature inductive platform preheating was used to fabricate intermetallic TiAl-alloy samples. The gas atomized (GA) and mechanically alloyed plasma spheroidized (MAPS) powders of the Ti-48Al-2Cr-2Nb (at. %) alloy were used as the feedstock material. The effects of L-PBF process parameters—platform preheating temperature—on the relative density, microstructure, phase composition, and mechanical properties of printed material were evaluated. Crack-free intermetallic samples with a high relative density of 99.9% were fabricated using 900 °C preheating temperature. Scanning electron microscopy and X-Ray diffraction analyses revealed a very fine microstructure consisting of lamellar α2/γ colonies, equiaxed γ grains, and retained β phase. Compressive tests showed superior properties of AM material as compared to the conventional TiAl-alloy. However, increased oxygen content was detected in MAPS powder compared to GA powder (~1.1 wt. % and ~0.1 wt. %, respectively), which resulted in lower compressive strength and strain, but higher microhardness compared to the samples produced from GA powder.

show abstract

Section: Introductionmentioning

confidence: 99%

Additive Manufacturing of Ti-48Al-2Cr-2Nb Alloy Using Gas Atomized and Mechanically Alloyed Plasma Spheroidized Powders

et al. 2020

View full text Add to dashboard Cite

show abstract

“…For tailoring TiAl alloys with optimum properties, laser powder bed fusion (L-PBF) and electron beam melting have been considered suitable [63][64][65][66]. Recently, the production of TiAl alloys using L-PBF has gained special attention [29,[67][68][69][70][71] owing to the benefits offered. Some of these benefits [6] complex geometry formation, ease of part dimension control, production of highly defined parts with orifices, mass customisation and material flexibility.…”

Section: Process Overviewmentioning

confidence: 99%

“…One needs to understand the crack and pore formation mechanisms and the defectprocess parameter relationships in such a case. Shi and associates [70] investigated [72].…”

Section: Research Milestonesmentioning

confidence: 99%

“…Although much work has been devoted to understanding the hot corrosion kinetics of Ni-based and Co-based superalloys, TiAl alloys emerged to have sparked much interest in recent years [1,56,57,139]. Historically, reported works utilised alloys produced using conventional methods; however, more attention has recently shifted to AM routes [70,73,[140][141][142][143][144][145][146]. Despite much devotion to improving structure-property relations of TiAls, little work has been reported on the hot corrosion of additively manufactured TiAl.…”

Section: Hot Corrosion Studies For Tial Alloysmentioning

confidence: 99%

See 1 more Smart Citation

Hot Corrosion and Oxidation Behaviour of TiAl Alloys during Fabrication by Laser Powder Bed Additive Manufacturing Process

Mogale¹,

Matizamhuka²,

Cobbinah³

2022

Corrosion - Fundamentals and Protection Mechanisms

View full text Add to dashboard Cite

This research paper summarises the practical relevance of additive manufacturing with particular attention to the latest laser powder bed fusion (L-PBF) technology. L-PBF is a promising processing technique, integrating intelligent and advanced manufacturing systems for aerospace gas turbine components. Some of the added benefits of implementing such technologies compared to traditional processing methods include the freedom to customise high complexity components and rapid prototyping. Titanium aluminide (TiAl) alloys used in harsh environmental settings of turbomachinery, such as low-pressure turbine blades, have gained much interest. TiAl alloys are deemed by researchers as replacement candidates for the heavier Ni-based superalloys due to attractive properties like high strength, creep resistance, excellent resistance to corrosion and wear at elevated temperatures. Several conventional processing technologies such as ingot metallurgy, casting, and solid-state powder sintering can also be utilised to manufacture TiAl alloys employed in high-temperature applications. This chapter focuses on compositional variations, microstructure, and processing of TiAl alloys via L-PBF. Afterward, the hot corrosion aspects of TiAl alloys, including classification, characteristics, mechanisms and preventative measures, are discussed. Oxidation behaviour, kinetics and prevention control measures such as surface and alloy modifications of TiAl alloys at high temperature are assessed. Development trends for improving the hot corrosion and oxidation resistance of TiAl alloys possibly affecting future use of TiAl alloys are identified.

show abstract

“…Additive Manufacturing (AM) is a promising way to manufacture intermetallic alloy parts since it offers significant advantages in terms of design freedom and cost reduction compared to conventional methods. However, high cooling rates typical for powder bed AM techniques lead to high residual stresses which makes it difficult to produce crack-free intermetallic parts [4]. The published data indicates that high-temperature preheating is needed to obtain crack-free intermetallic parts [5].…”

Section: Introductionmentioning

confidence: 99%

Microstructure and mechanical properties of TiAl-based alloy produced by selective laser melting

Polozov

Kantyukov

Popovich

et al. 2020

METAL 2020 Conference Proeedings

View full text Add to dashboard Cite

Additive Manufacturing (AM) is an attractive way of producing parts of intermetallic titanium alloys. However, high brittleness of these alloys makes it challenging to produce crack-free intermetallic parts by AM. One way to overcome this problem is to use high-temperature powder-bed preheating. In this paper, Ti-48Al-2Cr-2Nb alloy was obtained by selective laser melting process with high-temperature preheating of 800-900 ºC. Crackfree specimens with a relative density of 99.9% were fabricated using an optimized process parameter set. Microstructure and phase composition were studied using scanning electron microscopy and X-Ray diffraction to reveal a fine microstructure consisting of lamellar α2/γ colonies, equiaxed γ grains, and retained β phase. Compressive tests and microhardness measurements showed that the produced alloy exhibited superior properties compared to the conventionally obtained TiAl-alloy.

show abstract

The crack and pore formation mechanism of Ti–47Al–2Cr–2Nb alloy fabricated by selective laser melting

Cited by 45 publications

References 37 publications

Additive Manufacturing of Ti-48Al-2Cr-2Nb Alloy Using Gas Atomized and Mechanically Alloyed Plasma Spheroidized Powders

Additive Manufacturing of Ti-48Al-2Cr-2Nb Alloy Using Gas Atomized and Mechanically Alloyed Plasma Spheroidized Powders

Hot Corrosion and Oxidation Behaviour of TiAl Alloys during Fabrication by Laser Powder Bed Additive Manufacturing Process

Microstructure and mechanical properties of TiAl-based alloy produced by selective laser melting

Contact Info

Product

Resources

About