Influence of processing on microstructure and mechanical properties of (α+β) titanium alloys
15 Mar 1998-Materials Science and Engineering A-structural Materials Properties Microstructure and Processing (Elsevier)-Vol. 243, Iss: 1, pp 32-45
TL;DR: In this paper, the relationship between processing, microstructure, and mechanical properties of two-phase (α+β) titanium alloys is summarized and the advantages of a bi-modal (duplex) type of micro-structure usable for most applications are discussed.
Abstract: The present paper tries to summarize the relationship between processing, microstructure, and mechanical properties of two-phase (α+β) titanium alloys. Although for most structural applications of titanium alloys a variety of important mechanical properties (yield stress, ductility, HCF, LCF, da/dN of micro- and macrocracks, KIC, and creep) have to be optimized or balanced, and although both processing as well as microstructure contain many variables, it can be shown that from the numerous correlation possibilities only a few underlying basic principles are really important. One of them is the relationship between cooling rate, colony size, and slip length leading directly to the advantages of a bi-modal (duplex) type of microstructure usable for most applications and involving a reproducible and insensitive processing route.
Citations
More filters
TL;DR: In this paper, the effect of several heat treatments on the microstructure and mechanical properties of Ti6Al4V processed by Selective Laser Melting (SLM) is studied.
1,320 citations
20 Oct 2014-Materials Science and Engineering A-structural Materials Properties Microstructure and Processing
TL;DR: In this paper, the effect of the microstructure on the tensile properties of additive manufacturing (AM) of Ti alloys has been investigated. And the authors found that the mechanical anisotropy of the parts was discussed in relation to the crystallographic texture, phase composition and the predominant fracture mechanisms.
Abstract: Recent research on the additive manufacturing (AM) of Ti alloys has shown that the mechanical properties of the parts are affected by the characteristic microstructure that originates from the AM process. To understand the effect of the microstructure on the tensile properties, selective laser melted (SLM) Ti–6Al–4V samples built in three different orientations were tensile tested. The investigated samples were near fully dense, in two distinct conditions, as-built and stress relieved. It was found that the build orientation affects the tensile properties, and in particular the ductility of the samples. The mechanical anisotropy of the parts was discussed in relation to the crystallographic texture, phase composition and the predominant fracture mechanisms. Fractography and electron backscatter diffraction (EBSD) results indicate that the predominant fracture mechanism is intergranular fracture present along the grain boundaries and thus provide and explain the typical fracture surface features observed in fracture AM Ti–6Al–4V.
671 citations
TL;DR: In this paper, the macrostructure, microstructure and mechanical properties of a Ti-6Al-4V alloy after WAAM deposition have been investigated, and the average yield and ultimate tensile strengths of the as-deposited material were found to be slightly lower than those for a forged Ti- 6Al 4V bar (MIL-T 9047), however, the ductility was similar and the mean fatigue life was significantly higher.
Abstract: Wire and arc additive manufacturing (WAAM) is a novel manufacturing technique in which large metal components can be fabricated layer by layer. In this study, the macrostructure, microstructure, and mechanical properties of a Ti-6Al-4V alloy after WAAM deposition have been investigated. The macrostructure of the arc-deposited Ti-6Al-4V was characterized by epitaxial growth of large columnar prior-β grains up through the deposited layers, while the microstructure consisted of fine Widmanstatten α in the upper deposited layers and a banded coarsened Widmanstatten lamella α in the lower layers. This structure developed due to the repeated rapid heating and cooling thermal cycling that occurs during the WAAM process. The average yield and ultimate tensile strengths of the as-deposited material were found to be slightly lower than those for a forged Ti-6Al-4V bar (MIL-T 9047); however, the ductility was similar and, importantly, the mean fatigue life was significantly higher. A small number of WAAM specimens exhibited early fatigue failure, which can be attributed to the rare occurrence of gas pores formed during deposition.
512 citations
TL;DR: Shaped metal deposition (SMD) is a relatively new technology of additive manufacturing, which creates near-net shaped components by additive manufacture utilizing tungsten inert gas welding as mentioned in this paper, which has great advantages.
501 citations
TL;DR: In this article, the microstructure and mechanical properties of SLM and EBM Ti-6Al-4V samples have been compared and the effect of part size and orientation on the defects, micro-structure, and their contribution to the tensile and fatigue properties were elucidated.
481 citations
References
More filters