One-Dimensional Constitutive Model for Porous Titanium Alloy at Various Strain Rates and Temperatures

Abstract

Abstract:In this paper, the accurate description of the relationship between flow stress and strain of porous titanium alloys at various strain rates and temperatures were investigated with dynamic and quasistatic uniaxial compression tests for a further study on the processing mechanism of porous titanium material. Changes in their plastic flows were described through the one-dimensional Drucker-Prager (DP) constitutive model. Porous titanium alloys were micromilled in a DP simulation. After all parameters had been obtained in the DP model, the experimental and simulated true stress-strain curves and flow stress levels of two porous titanium alloys were compared to estimate the precision of the model. The findings were as follows. First, porous titanium alloys show deformation patterns characterized by pore collapse-induced deformation and have strong stress-hardening effects, but the patterns did not include noticeable plastic-flow plateaus. Second, porosity strongly affects the mechanical strength, strain-rate sensitivity, and temperature sensitivity of both alloys. Third, the DP model sufficiently describes the mechanical properties of both alloys at 25-300 • C and at strain rates of 1000-3000 s −1 , with a deviation of 10% or lower.

Finite element analysis of porous commercially pure titanium for biomedical implant application

“…This phenomenon is associated with local damage of the material, which can be described as brittle crushing: localised damage from excessive plastic strain propagates through the porous network. Similar types of failure have been observed by Z. Liu et al [33] with levels of porosity in the same range as investigated here (26% and 36%). True stress-strain curves in uniaxial compression for (a) dense titanium (b) 27% porous titanium (Ti_30) (c) 35% porous titanium (Ti_40).…”

Additive manufacturing and mechanical properties of titanium lattices for biomedical applications

“…This phenomenon is associated with local damage of the material, which can be described as brittle crushing: localised damage from excessive plastic strain propagates through the porous network. Similar types of failure have been observed by Z. Liu et al[182] with levels of porosity in the same range as investigated here (26% and 36%).…”

Application of Machine Learning in Constitutive Relationship Prediction of Porous Titanium Materials for Artificial Bone

“…Affected by the microstructure strain efficiency and the matrix material, porous titanium has strain rate sensitivity due to the influence of its matrix material [5,[32][33][34]. From the perspective of the microstructure, the pore wall of porous titanium has plastic bending during the compression process, so the strain rate effect will be produced.…”