PSI - Issue 39

ScienceDirect Structural Integrity Procedia 00 (2019) 000–000 Structural Integrity Procedia 00 (2019) 000–000 Available online at www.sciencedirect.com Available online at www.sciencedirect.com ScienceD rect Available online at www.sciencedirect.com ScienceDirect

www.elsevier.com/locate/procedia www.elsevier.com/locate/procedia

Procedia Structural Integrity 39 (2022) 327–332

© 2021 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of CP 2021 – Guest Editors Abstract The in-service fatigue fracture of the fan disk from the titanium alloy was considered and analyzed. Fatigue crack started from the cut which was produced during disk manufacturing and located along the slot for the blade. The crack path was performed by the mechanism of crack meso-tunneling with the facetted pattern relief and striation formation on the fracture surface. Based on the fractographic analysis, equivalent stress for various values of crack length was estimated. The inspection interval for reliable crack registration in the disk was provided. It was demonstrated that without cuts the disk in-service period will be not less than 15,000 flights. © 2021 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of CP 2021 – Guest Editors Keywords: forged titanium disk; in-service failure; crack path 1. Introduction Disks of gas-turbine engines (GTE) are traditionally manufactured from various titanium alloys and operate under high-stress conditions. A stress state of the disks is considered in terms of repetitive cycles of variable loads, which represent a load block for a flight or a cycle of starting and stopping the engine. In the mid-1980s the problem of the fatigue crack propagation in disks of gas-turbine engines appeared and it was discussed, for example, in Shanyavskiy and Stepanov (1995), Shanyavskiy et al. (1998), Shanyavskiy and Losev (1999), Shanyavskiy (2003), McEvily (2004). This problem is generally associated with the structural features of two- Abstract The in-service fatigue fracture of the fan disk from the titanium alloy was considered and analyzed. Fatigue crack started from the cut which was prod ced during disk manufacturing and located l ng the slot for the blade. The crack path w s performed by mechanism of c ack meso-tu nel ng with the facetted pattern relief and striation formation on the fracture surfac . Bas on fra tographic analysis, quivalent stress for various values of c ack length w s estimated. The insp ction interval for reliable crack registration in the disk was provided. It was demonstrat d that without cuts the disk in-service period will be not less th n 15,000 fli h s. © 2021 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review u der re ponsibility of CP 2021 – Guest Editors Keywords: forged titanium disk; in-service failure; crack path 1. Introduction Disks of gas-turbine engines (GTE) are traditionally manufactured from various titanium alloys and operate under high- tress conditions. A stres state of the disks is considered in t rms of repetitive cycles of vari ble loads, which repre ent a l a bl ck for a flight or a cycl of starting an stopping the engine. In the mid-1980s the prob em f the fatigue crack propagation in disks of gas-turbine engines appeared and it was discuss d, for exampl , in Shanyavskiy and Stepanov (1995), Shanyavskiy et al. (1998), Shanyavskiy Losev (1999), Shanyavskiy (2003), McEvily (2004). This pr blem is gener ll a socia ed with the structur l features of two- 7th International Conference on Crack Paths Crack path of in-service fatigued fan titanium disk of D-18T gas turbine engine of the aircraft An-124 Andrey Shanyavskiy a *, Aleksey Soldatenkov a a Aviation Register for Russian Federation, Airport Sheremetievo-1, PO Box 54, Moscow region, Chimkinskiy State, 141426, Russia 7th International Conference on Crack Paths Crack path of in-service fatigued fan titanium disk of D-18T gas turbine engine of the aircraft An-124 Andrey Shanyavskiy a *, Aleksey Soldatenkov a a Aviation Register for Russian Federation, Airport Sheremetievo-1, PO Box 54, Moscow region, Chimkinskiy State, 141426, Russia

* Corresponding author. Tel.: +7-495-578-5288; fax: +7-495-730-6094. E-mail address: 106otdel@mail.ru * Corresponding author. Tel.: +7-495-578-5288; fax: +7-495-730-6094. E-mail address: 106otdel@mail.ru

2452-3216 © 2021 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of CP 2021 – Guest Editors 2452-3216 © 2021 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of CP 2021 – Guest Editors

2452-3216 © 2021 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of CP 2021 – Guest Editors 10.1016/j.prostr.2022.03.102