The effect of strain rate on the compressive deformation behavior of a sintered Ti6Al4V powder compact

Abstract

The high strain rate (220-550 s −1 ) and quasi-static (0.0016 s −1 ) compression deformation behavior of a sintered Ti6Al4V powder compact was investigated. The compact was prepared using atomized spherical particles (100-200 m) and contained 38 ± 1% porosity. The deformation sequences of the tested samples were further recorded by high speed camera and analyzed as a function of strain. The failure of the compact, which was found to be similar in the studied high strain rate and quasi-static strain rate testing regimes, occurs through particle decohesion along the surface of the two cones in a ductile (dimpled) mode consisting of void initiation and growth and by void coalescence in the interparticle bond region. The effect of strain rate was to increase the flow stress and compressive strength of the compact while the critical strain corresponding to the maximum stress was shown to be strain rate independent.

Processing and compression testing of Ti6Al4V foams for biomedical applications

“…In densification region, the material stress increases sharply and approaches the strength of the bulk metal. The compression deformation behavior of sintered porous Ti64 powder (100-200 lm) compacts of 38% porosity with an average pore size of 63 lm was previously studied [11]. The compacts formed deformation zones diagonal to the sample axis at relatively low strains, 4-5%.…”

“…At increasing sintering temperatures the foams however show partly sintered compact behavior and partly foamed metal behavior. Figure 15 compares the compression stress-strain behavior of the previously studied porous Ti64 compacts [11] and Ti foams [12] with those of Powder 1 and Powder 2 foams sintered at 1,350°C. Ti foams prepared with smaller particle sizes had relatively dense cell walls/edges with small micropores (1-10 lm) in the cell walls and, therefore, showed compression behaviors similar to those of open cell foams.…”

Ultralow Temperature Densification of a Titanium Alloy by Spark Plasma Sintering

“…Sintering of Ti6Al4V has been widely investigated in pressureless and pressure‐assisted powder metallurgy routes . Figure shows a visual summary of the commonly used sintering techniques in the processing of Ti6Al4V prealloyed powders.…”

“…Comparative chart of pressureless and pressure‐assisted sintering routes conventionally used for the densification of Ti6Al4V. A processing gap is identified and investigated with potential advantages for Ti nanofiller composites …”

“…Sintering of Ti6Al4V has been widely investigated in pressureless and pressure-assisted powder metallurgy routes. [8][9][10]15,[29][30][31][32][33][34][35][36][37][38][39][40][41] Figure 5 shows a visual summary of the commonly used sintering techniques in the processing of Ti6Al4V prealloyed powders. Among two common sintering regimes for the densification of the alloy (1) and (2), this work outlines the emergence of a third regime (3) denominated as a "processing gap" (<800 C).…”