Multi-scale and multi-technic microstructure analysis of a linear friction weld of the metastable-beta titanium alloy Ti-5Al-2Sn-2Zr-4Mo-4Cr (Ti17) towards a new Post-Weld Heat Treatment

Dorick Ballat-Durand, Salima Bouvier*, Marion Risbet, Wolfgang Pantleon

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

Linear Friction Welding (LFW) is a solid-state joining process producing narrow joints mainly developed for the aircraft industry. The Thermo-Mechanical Processing (TMP) loads imposed on the material cause complex microstructure transformations. This study aimed at characterizing the local microstructures and crystallographic configurations to identify the mechanisms impacting the stability and the mechanical properties of a Ti17 LFW joint with the objective of establishing an innovative homogenizing Post-Weld Heat Treatment (PWHT). The process caused a narrow zone of +/- 2 mm from the friction interface to reach the isothermal a -> beta transformation temperature under a heating rate of 500 K/s followed by quenching (-100 K/s). The TMP resulted in the formation a +/- 3 mm wide soft Process Affected Zone (PAZ) delimited by three characteristic zones: the Welding Line (WL width approximate to 400 mu m), The Thermo-Mechanically Affected Zone (TMAZ width approximate to 1 mm) and the Heat Affected Zone (HAZ). beta TMP resulted in the total dissolution of the alpha phase in the joint core (WL + TMAZ) and formed strongly textured {110} beta recrystallized grains in the WL by continuous dynamic recrystallization of squeezed prior-beta grains in the TMAZ. alpha + beta TMP led to a gradual loss of hardness in the HAZ whose microstructure is similar to the one of the base material (BM) but is subject to gradual a laths dissolution due to the local temperatures experienced during LFW. A PWHT consisting in a beta annealing followed by an alpha + beta ageing resulted in a uniformly hardened weld with a homogenized Widmanstatten microstructure in the whole assembly.
Original languageEnglish
JournalMaterials Characterization
Volume144
Pages (from-to)661-670
Number of pages10
ISSN1044-5803
DOIs
Publication statusPublished - 2018

Cite this

@article{f8dee21a8abe4586a76b304b225d1976,
title = "Multi-scale and multi-technic microstructure analysis of a linear friction weld of the metastable-beta titanium alloy Ti-5Al-2Sn-2Zr-4Mo-4Cr (Ti17) towards a new Post-Weld Heat Treatment",
abstract = "Linear Friction Welding (LFW) is a solid-state joining process producing narrow joints mainly developed for the aircraft industry. The Thermo-Mechanical Processing (TMP) loads imposed on the material cause complex microstructure transformations. This study aimed at characterizing the local microstructures and crystallographic configurations to identify the mechanisms impacting the stability and the mechanical properties of a Ti17 LFW joint with the objective of establishing an innovative homogenizing Post-Weld Heat Treatment (PWHT). The process caused a narrow zone of +/- 2 mm from the friction interface to reach the isothermal a -> beta transformation temperature under a heating rate of 500 K/s followed by quenching (-100 K/s). The TMP resulted in the formation a +/- 3 mm wide soft Process Affected Zone (PAZ) delimited by three characteristic zones: the Welding Line (WL width approximate to 400 mu m), The Thermo-Mechanically Affected Zone (TMAZ width approximate to 1 mm) and the Heat Affected Zone (HAZ). beta TMP resulted in the total dissolution of the alpha phase in the joint core (WL + TMAZ) and formed strongly textured {110} beta recrystallized grains in the WL by continuous dynamic recrystallization of squeezed prior-beta grains in the TMAZ. alpha + beta TMP led to a gradual loss of hardness in the HAZ whose microstructure is similar to the one of the base material (BM) but is subject to gradual a laths dissolution due to the local temperatures experienced during LFW. A PWHT consisting in a beta annealing followed by an alpha + beta ageing resulted in a uniformly hardened weld with a homogenized Widmanstatten microstructure in the whole assembly.",
author = "Dorick Ballat-Durand and Salima Bouvier and Marion Risbet and Wolfgang Pantleon",
year = "2018",
doi = "10.1016/j.matchar.2018.08.013",
language = "English",
volume = "144",
pages = "661--670",
journal = "Materials Characterization",
issn = "1044-5803",
publisher = "Elsevier",

}

Multi-scale and multi-technic microstructure analysis of a linear friction weld of the metastable-beta titanium alloy Ti-5Al-2Sn-2Zr-4Mo-4Cr (Ti17) towards a new Post-Weld Heat Treatment. / Ballat-Durand, Dorick; Bouvier, Salima; Risbet, Marion; Pantleon, Wolfgang.

In: Materials Characterization, Vol. 144, 2018, p. 661-670.

Research output: Contribution to journalJournal articleResearchpeer-review

TY - JOUR

T1 - Multi-scale and multi-technic microstructure analysis of a linear friction weld of the metastable-beta titanium alloy Ti-5Al-2Sn-2Zr-4Mo-4Cr (Ti17) towards a new Post-Weld Heat Treatment

AU - Ballat-Durand, Dorick

AU - Bouvier, Salima

AU - Risbet, Marion

AU - Pantleon, Wolfgang

PY - 2018

Y1 - 2018

N2 - Linear Friction Welding (LFW) is a solid-state joining process producing narrow joints mainly developed for the aircraft industry. The Thermo-Mechanical Processing (TMP) loads imposed on the material cause complex microstructure transformations. This study aimed at characterizing the local microstructures and crystallographic configurations to identify the mechanisms impacting the stability and the mechanical properties of a Ti17 LFW joint with the objective of establishing an innovative homogenizing Post-Weld Heat Treatment (PWHT). The process caused a narrow zone of +/- 2 mm from the friction interface to reach the isothermal a -> beta transformation temperature under a heating rate of 500 K/s followed by quenching (-100 K/s). The TMP resulted in the formation a +/- 3 mm wide soft Process Affected Zone (PAZ) delimited by three characteristic zones: the Welding Line (WL width approximate to 400 mu m), The Thermo-Mechanically Affected Zone (TMAZ width approximate to 1 mm) and the Heat Affected Zone (HAZ). beta TMP resulted in the total dissolution of the alpha phase in the joint core (WL + TMAZ) and formed strongly textured {110} beta recrystallized grains in the WL by continuous dynamic recrystallization of squeezed prior-beta grains in the TMAZ. alpha + beta TMP led to a gradual loss of hardness in the HAZ whose microstructure is similar to the one of the base material (BM) but is subject to gradual a laths dissolution due to the local temperatures experienced during LFW. A PWHT consisting in a beta annealing followed by an alpha + beta ageing resulted in a uniformly hardened weld with a homogenized Widmanstatten microstructure in the whole assembly.

AB - Linear Friction Welding (LFW) is a solid-state joining process producing narrow joints mainly developed for the aircraft industry. The Thermo-Mechanical Processing (TMP) loads imposed on the material cause complex microstructure transformations. This study aimed at characterizing the local microstructures and crystallographic configurations to identify the mechanisms impacting the stability and the mechanical properties of a Ti17 LFW joint with the objective of establishing an innovative homogenizing Post-Weld Heat Treatment (PWHT). The process caused a narrow zone of +/- 2 mm from the friction interface to reach the isothermal a -> beta transformation temperature under a heating rate of 500 K/s followed by quenching (-100 K/s). The TMP resulted in the formation a +/- 3 mm wide soft Process Affected Zone (PAZ) delimited by three characteristic zones: the Welding Line (WL width approximate to 400 mu m), The Thermo-Mechanically Affected Zone (TMAZ width approximate to 1 mm) and the Heat Affected Zone (HAZ). beta TMP resulted in the total dissolution of the alpha phase in the joint core (WL + TMAZ) and formed strongly textured {110} beta recrystallized grains in the WL by continuous dynamic recrystallization of squeezed prior-beta grains in the TMAZ. alpha + beta TMP led to a gradual loss of hardness in the HAZ whose microstructure is similar to the one of the base material (BM) but is subject to gradual a laths dissolution due to the local temperatures experienced during LFW. A PWHT consisting in a beta annealing followed by an alpha + beta ageing resulted in a uniformly hardened weld with a homogenized Widmanstatten microstructure in the whole assembly.

U2 - 10.1016/j.matchar.2018.08.013

DO - 10.1016/j.matchar.2018.08.013

M3 - Journal article

VL - 144

SP - 661

EP - 670

JO - Materials Characterization

JF - Materials Characterization

SN - 1044-5803

ER -