scholarly journals Dynamic Mechanical Response of Biomedical 316L Stainless Steel as Function of Strain Rate and Temperature

2011 ◽  
Vol 2011 ◽  
pp. 1-13 ◽  
Author(s):  
Woei-Shyan Lee ◽  
Tao-Hsing Chen ◽  
Chi-Feng Lin ◽  
Wen-Zhen Luo
Keyword(s):  
Activation Energy ◽  
Stainless Steel ◽  
Flow Stress ◽  
Strain Rate ◽  
Thermal Activation ◽  
316L Stainless Steel ◽  
Rate Sensitivity ◽  
Thermal Activation Energy ◽  
Work Hardening Rate ◽  
Stress Work

A split Hopkinson pressure bar is used to investigate the dynamic mechanical properties of biomedical 316L stainless steel under strain rates ranging from 1 × 103 s-1to 5 × 103 s-1and temperatures between25∘Cand800∘C. The results indicate that the flow stress, work-hardening rate, strain rate sensitivity, and thermal activation energy are all significantly dependent on the strain, strain rate, and temperature. For a constant temperature, the flow stress, work-hardening rate, and strain rate sensitivity increase with increasing strain rate, while the thermal activation energy decreases. Catastrophic failure occurs only for the specimens deformed at a strain rate of 5 × 103 s-1and temperatures of25∘Cor200∘C. Scanning electron microscopy observations show that the specimens fracture in a ductile shear mode. Optical microscopy analyses reveal that the number of slip bands within the grains increases with an increasing strain rate. Moreover, a dynamic recrystallisation of the deformed microstructure is observed in the specimens tested at the highest temperature of800∘C.

Effects of prestrain on high temperature impact properties of 304L stainless steel

2010 ◽  
Vol 25 (4) ◽  
pp. 754-763 ◽  
Author(s):  
Woei-Shyan Lee ◽  
Chi-Feng Lin ◽  
Tao-Hsing Chen ◽  
Meng-Chieh Yang
Keyword(s):  
Stainless Steel ◽  
Flow Stress ◽  
Strain Rate ◽  
Work Hardening ◽  
Rate Sensitivity ◽  
304L Stainless Steel ◽  
Impact Properties ◽  
Work Hardening Rate ◽  
The Impact ◽  
Sensitivity Increase

The effects of prestrain, strain rate, and temperature on the impact properties of 304L stainless steel are investigated using a compressive split-Hopkinson pressure bar. The impact tests are performed at strain rates ranging from 2000 to 6000 s−1 and temperatures of 300, 500, and 800 °C using 304L specimens with prestrains of 0.15 or 0.5. The results show that the flow stress, work-hardening rate, and strain rate sensitivity increase with increasing strain rate or decreasing temperature. As the prestrain increases, the flow stress and strain rate sensitivity increase, but the work-hardening rate decreases. The temperature sensitivity increases with an increasing strain rate, temperature, and prestrain. Overall, the effects of prestrain on the impact properties of the tested specimens dominate those of the strain rate or temperature, respectively. Finally, optical microscopy observations reveal that the specimens fracture primarily as the result of the formation of adiabatic shear bands.

Effect of Hot Extrusion on the Flow Behaviour of a Nickel-Based P/M Superalloy

2019 ◽  
Vol 298 ◽  
pp. 43-51
Author(s):  
Jia Yong Si ◽  
Song Hao Liu ◽  
Long Chen
Keyword(s):  
Activation Energy ◽  
Strain Rate ◽  
Strain Rate Sensitivity ◽  
Work Hardening ◽  
Rate Sensitivity ◽  
Hot Extrusion ◽  
Turbine Disk ◽  
Flow Behaviour ◽  
Strain Rates ◽  
Work Hardening Rate

This research investigated the effect of hot extrusion on the flow behaviour of nickel-based superalloy FGH4096 by hot compression experiments in the temperature range from 1020 to 1110 °C and strain rates ranging from 0.1 to 0.001 s-1. The influence of the hot extrusion on the initial microstructures, work hardening rate, strain rate sensitivity, and activation energy of deformation were discussed. The results show that the extruded microstructure is constituted by the fine dynamic recrystallisation of grains. The true strain-true stress curves show that the as-HIPed and as-HEXed FGH4096 superalloy present double flow stress peaks and discontinuous flow softening. The as-HEXed FGH4096 is easily dynamically softened at high temperatures and high strain rates compared with as-HIPed microstructures. As for the work hardening rate, the as-HEXed FGH4096 exhibits higher θ values than that of as-HIPed. It is beneficial to the homogenous deformation and grain refinement during subsequent turbine disk forging. Comparing to as-HIPed FGH4096, the highest strain rate sensitivity value of as-HEXed is 0.306 at 1110 °C. The isothermal superplastic forging of a P/M turbine disk may be carried out at this temperature. The deformation activation energy value of the as-HIPed FGH4096 is lower which means that dislocation sliding and climbing can be easily initiated in the as-HIPed alloy.

scholarly journals On the effects of build orientation, strain rate sensitivity and sample thickness on the mechanical behavior of 316l Stainless Steel manufactured by Selective Laser Melting

2021 ◽  
Vol 250 ◽  
pp. 05009
Author(s):  
Hugo Carassus ◽  
Hervé Morvan ◽  
Gregory Haugou ◽  
Jean-Dominique Guerin ◽  
Tarik Sadat ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Stainless Steel ◽  
Strain Rate ◽  
Mechanical Behavior ◽  
Selective Laser Melting ◽  
Strain Rate Sensitivity ◽  
316L Stainless Steel ◽  
Rate Sensitivity ◽  
Thickness Variation ◽  
Laser Melting

The Additive Layer Manufacturing (ALM) for metallic materials has grown in the past few years. However, this process influences the mechanical properties of the constitutive material and consequently those of the finished product. The influence of the thickness and the building direction of 316L Stainless Steel (SS) specimens produced by Selective Laser Melting (SLM) on the quasi-static mechanical behavior has already been reported. Considering the strain rate effect, it has been only studied for tensile properties of vertical specimens up to 102s–1. The aim of this work is to study the influence of the thickness and the building orientation at higher strain rates up to 101s–1 and up to 103s–1 for vertical specimens. Compared to conventional material, 316L SS SLM achieves equal and even better mechanical properties due to a refinement of the microstructure. Anisotropy is observed at the macroscopic level, which is explained by the microstructure with different shapes, orientation and size of grains. A minimum thickness of 0.75mm is recommended to recover the mechanical properties of the conventional 316L SS. A positive strain rate sensitivity is observed in every case. The material anisotropy and the thickness variation do not affect the strain rate sensitivity.

scholarly journals Effect of changing strain rate on flow stress during hot deformation of Type 316L stainless steel

2008 ◽  
Vol 491 (1-2) ◽  
pp. 290-296 ◽  
Author(s):  
M.F. Abbod ◽  
C.M. Sellars ◽  
A. Tanaka ◽  
D.A. Linkens ◽  
M. Mahfouf
Keyword(s):  
Stainless Steel ◽  
Flow Stress ◽  
Strain Rate ◽  
Hot Deformation ◽  
316L Stainless Steel ◽  
Type 316L ◽  
Type 316L Stainless Steel

Effects of Deformation Heating on Constitutive Analysis of a New Al-Mg-Si-Cu Alloy during Hot Compression

2014 ◽  
Vol 794-796 ◽  
pp. 1263-1268 ◽  
Author(s):  
Dong Yang ◽  
Yong Hong Quan ◽  
Huan Zhao ◽  
Zhi Qing Zhang ◽  
Guang Jie Huang ◽  
...  
Keyword(s):  
Activation Energy ◽  
Flow Stress ◽  
Thermal Activation ◽  
Thermal Activation Energy ◽  
Strain Rates ◽  
Deformation Heating ◽  
Constitutive Analysis ◽  
Cu Alloy ◽  
Hyperbolic Sine ◽  
Before And After

A new Al-Mg-Si-Cu aluminum alloy was hot compressed at temperatures between 320°Cand 530°Cand strain rates between 0.001 s1and 10 s1using a Gleeble-1500 thermo-simulation machine. The effects of deformation heating on flow stress were analyzed and corrected, and a comparison was made of hyperbolic-sine constitutive equations with and without correction. The results show that the deformation heating apparently increases the flow stress at strain rates of 1 s1, 10 s1. The thermal activation energy values were 325.12 KJ/mol and 304.47 KJ/mol before and after correction, respectively.

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