Numerical Investigation of the High Strain Rate Behavior of Superelastic NiTi Alloys

Umut Caliskan; Güher Pelin Toker

Article Details

Numerical Investigation of the High Strain Rate Behavior of Superelastic NiTi Alloys

Authors:

Umut Caliskan | Güher Pelin Toker

Publisher:

Erciyes University

Main Topics:

Sayısal Modelleme ve Mekanik Karakterizasyon | Malzeme Karekterizasyonu

Journal:

Enginoscope Vol.1 Issue 2, pp.165-177

Document Type:

Article

Publication Date:

7/2025

Document Language:

English

Document ID (Org No.):

2001355855

pISSN:

3062-2360

Keywords:

Abstract:

 This study presents a finite element-based numerical investigation of the high strain rate behavior of superelastic NiTi shape memory alloys SMAs using the built-in superelastic material model in ABAQUSExplicit. Dynamic compression simulations inspired by Split Hopkinson Pressure Bar SHPB loading were conducted at projectile velocities of 5, 10, 20, and 40 ms. A cylindrical NiTi specimen with 6 mm length and 6 mm diameter was modeled under axial impact loading conditions. The superelastic response of the alloy was defined using standard material parameters representative of Ti50.8 at. Ni compositions, including distinct elastic moduli for austenite and martensite, transformation strain, and stress thresholds for forward and reverse phase transformation. Strain rate values were computed based on nodal velocity differences at the specimen ends, resulting in a transition from moderate to extreme strain rate regimes ranging approximately from 600 to over 7000 s¹. Simulation results revealed clear rate-dependent behavior in phase transformation onset, strain capacity, and hysteresis width.

 This study presents a finite element-based numerical investigation of the high strain rate behavior of superelastic NiTi shape memory alloys SMAs using the built-in superelastic material model in ABAQUSExplicit. Dynamic compression simulations inspired by Split Hopkinson Pressure Bar SHPB loading were conducted at projectile velocities of 5, 10, 20, and 40 ms. A cylindrical NiTi specimen with 6 mm length and 6 mm diameter was modeled under axial impact loading conditions. The superelastic response of the alloy was defined using standard material parameters representative of Ti50.8 at. Ni compositions, including distinct elastic moduli for austenite and martensite, transformation strain, and stress thresholds for forward and reverse phase transformation. Strain rate values were computed based on nodal velocity differences at the specimen ends, resulting in a transition from moderate to extreme strain rate regimes ranging approximately from 600 to over 7000 s¹. Simulation results revealed clear rate-dependent behavior in phase transformation onset, strain capacity, and hysteresis width.

 This study presents a finite element-based numerical investigation of the high strain rate behavior of superelastic NiTi shape memory alloys SMAs using the built-in superelastic material model in ABAQUSExplicit. Dynamic compression simulations inspired by Split Hopkinson Pressure Bar SHPB loading were conducted at projectile velocities of 5, 10, 20, and 40 ms. A cylindrical NiTi specimen with 6 mm length and 6 mm diameter was modeled under axial impact loading conditions. The superelastic response of the alloy was defined using standard material parameters representative of Ti50.8 at. Ni compositions, including distinct elastic moduli for austenite and martensite, transformation strain, and stress thresholds for forward and reverse phase transformation. Strain rate values were computed based on nodal velocity differences at the specimen ends, resulting in a transition from moderate to extreme strain rate regimes ranging approximately from 600 to over 7000 s¹. Simulation results revealed clear rate-dependent behavior in phase transformation onset, strain capacity, and hysteresis width.

 Bu çalışma, ABAQUSExplicit yazılımındaki yerleşik süperelastik malzeme modeli kullanılarak, süperelastik NiTi şekil hafızalı alaşımların yüksek gerinim hızlarındaki davranışının sonlu elemanlar yöntemiyle sayısal olarak incelenmesini sunmaktadır. Split Hopkinson Basma Çubuğu SHPB yükleme koşullarından esinlenilerek, 5, 10, 20 ve 40 ms çarpma hızlarında dinamik basma simülasyonları gerçekleştirilmiştir. Eksene paralel darbe yüklemesine maruz bırakılan NiTi numunesi, 6 mm uzunluk ve 6 mm çapa sahip silindirik bir geometri ile modellenmiştir. Süperelastik davranış, Ti50.8 at. Ni alaşımı karakteristiğini temsil eden standart malzeme parametreleri kullanılarak tanımlanmıştır. Bu tanım; östenit ve martensit fazlarına ait farklı elastik modüller, dönüşüm şekil değiştirmesi ve ilerigeri faz dönüşümüne ait gerilme eşiklerini içermektedir. Numune uçlarındaki nodal hız farklarına dayalı olarak hesaplanan gerinim hızı değerleri, yaklaşık 600-7000 s¹ arasında değişmiş ve orta ile çok yüksek gerinim hızı rejimleri arasında belirgin bir geçiş gözlemlenmiştir. Simülasyon sonuçları, faz dönüşüm başlangıcında gecikme, dönüşüm geriniminde azalma ve histerezis genişliğinde daralma ile kendini gösteren hız bağımlı davranışı net bir şekilde ortaya koymuştur.

Article Details

Numerical Investigation of the High Strain Rate Behavior of Superelastic NiTi Alloys

Authors:

Umut Caliskan | Güher Pelin Toker

Publisher:

Erciyes University

Main Topics:

Sayısal Modelleme ve Mekanik Karakterizasyon | Malzeme Karekterizasyonu

Journal:

Enginoscope Vol.1 Issue 2, pp.165-177

Document Type:

Article

Publication Date:

7/2025

Document Language:

English

Document ID (Org No.):

2001355855

pISSN:

3062-2360

Superelastic

NiTi alloys

High strain rate

ABAQUS/Explicit

Finite Element AnalysisSüperelastik

NiTi alaşımları

Yüksek gerinim hızı

ABAQUS/Explicit

Sonlu elemanlar analizi

Issues

Article Details

Authors: Umut Caliskan | Güher Pelin Toker

Publisher: Erciyes University

Main Topics: Sayısal Modelleme ve Mekanik Karakterizasyon | Malzeme Karekterizasyonu

Journal: Enginoscope Vol.1 Issue 2, pp.165-177

Document Type: Article

Publication Date: 7/2025

Document Language: English

Document ID (Org No.): 2001355855

pISSN: 3062-2360

Issues

Authors:

Umut Caliskan | Güher Pelin Toker

Publisher:

Erciyes University

Main Topics:

Sayısal Modelleme ve Mekanik Karakterizasyon | Malzeme Karekterizasyonu

Journal:

Enginoscope Vol.1 Issue 2, pp.165-177

Document Type:

Article

Publication Date:

7/2025

Document Language:

English

Document ID (Org No.):

2001355855

pISSN:

3062-2360