The effects of microstructure and porosity on the competing fatigue failure mechanisms in powder metallurgy Ti-6Al-4V
Source abstract
Abstract
Abstract In near-net-shape manufacturing methods, such as powder metallurgy, additive manufacturing, and metal injection molding, porosity has historically been viewed as the sole limiting factor for fatigue life. This is because pores tend to act as stress concentrators. However, in this work, a fractographic analysis of Ti-6Al-4V produced through several powder metallurgy techniques has shown that microstructural faceting due to slip can cause fatigue failure, even in the presence of porosity. The likelihood of pore related failure was found to be dependent on microstructure size and morphology. Additionally, a minimum pore size threshold was found to exist for each microstructure, under which pores will not cause fatigue failure. A simple model was developed to determine this threshold based on the microstructural characteristics of the material. This model was then compared to experimental data and properly predicted the fatigue failure mechanism in over 99% of the samples examined.
Source: openaire · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Powder Metallurgy Techniques and Materials · Injection Molding Process and Properties · Titanium Alloys Microstructure and Properties
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
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