Mechanical behavior at elevated temperatures of an Al–Mn–Mg–Sc–Zr alloy manufactured by selective laser melting

The article presents the results of selective laser melting of Ti-6Al-4V alloy. It was studied phase composition and microstructure of the initial powder material, the specimens manufactured by Selective Laser Melting and also the specimens after heat treatment. The effect of heat treatment on microstructure and mechanical properties of the specimens was shown. It was studied the mechanical behavior of the manufactured specimens before and after heat treatment at room and elevated temperatures as well. After heat treatment tests showed that the specimens have decent mechanical properties both at room and elevated temperatures.

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Laser Weldability of AlSi10Mg Alloy Produced by Selective Laser Melting: Microstructure and Mechanical Behavior

Journal of Materials Engineering and Performance ◽

10.1007/s11665-019-04402-7 ◽

2019 ◽

Vol 28 (11) ◽

pp. 6714-6719 ◽

Cited By ~ 4

Author(s):

Carlo Alberto Biffi ◽

Jacopo Fiocchi ◽

Ausonio Tuissi

Keyword(s):

Mechanical Behavior ◽

Selective Laser Melting ◽

Laser Melting

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Microstructure and Mechanical Properties of Ti-6Al-4V Manufactured by SLM

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.651-653.677 ◽

2015 ◽

Vol 651-653 ◽

pp. 677-682 ◽

Cited By ~ 33

Author(s):

Anatoliy Popovich ◽

Vadim Sufiiarov ◽

Evgenii Borisov ◽

Igor Polozov

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Phase Composition ◽

Mechanical Behavior ◽

Ductile Fracture ◽

Elevated Temperatures ◽

Initial Material ◽

Laser Melting ◽

Microstructure And Mechanical Properties ◽

Before And After

The article presents results of a study of phase composition and microstructure of initial material and samples obtained by selective laser melting of titanium-based alloy, as well as samples after heat treatment. The effect of heat treatment on microstructure and mechanical properties of specimens was shown. It was studied mechanical behavior of manufactured specimens before and after heat treatment at room and elevated temperatures as well. The heat treatment allows obtaining sufficient mechanical properties of material at room and elevated temperatures such as increase in ductility of material. The fractography of samples showed that they feature ductile fracture with brittle elements.

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Thermodynamic Behavior of Fe-Mn and Fe-Mn-Ag Powder Mixtures during Selective Laser Melting

Metals ◽

10.3390/met11020234 ◽

2021 ◽

Vol 11 (2) ◽

pp. 234

Author(s):

Jakob Kraner ◽

Jožef Medved ◽

Matjaž Godec ◽

Irena Paulin

Keyword(s):

Selective Laser Melting ◽

Manganese Oxides ◽

Elevated Temperatures ◽

Manganese Content ◽

Chemical Compositions ◽

Metal Powders ◽

Laser Melting ◽

Powder Mixtures ◽

Ε Martensite ◽

The Impact

Additive manufacturing is a form of powder metallurgy, which means the properties of the initial metal powders (chemical composition, powder morphology and size) impact the final properties of the resulting parts. A complete characterization, including thermodynamic effects and the behavior of the metal powders at elevated temperatures, is crucial when planning the manufacturing process. The analysis of the Fe-Mn and Fe-Mn-Ag powder mixtures, made from pure elemental powders, shows a high susceptibility to sintering in the temperature interval from 700 to 1000 °C. Here, numerous changes to the manganese oxides and the αMn to βMn transformation occurred. The problems of mechanically mixed powders, when using selective laser melting, were highlighted by the low flowability, which led to a less controllable process, an uncontrolled arrangement of the powder and a large percentage of burnt manganese. All this was determined from the altered chemical compositions of the produced parts. The impact of the increased manganese content on the decreased probability of the transformation from γ-austenite to ε-martensite was confirmed. The ε-martensite in the microstructure increased the hardness of the material, but at the same time, its magnetic properties reduce the usefulness for medical applications. However, the produced parts had comparable elongations to human bone.

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Martensite decomposition during post-heat treatments and the aging response of near-α Ti–6Al–2Sn–4Zr–2Mo (Ti-6242) titanium alloy processed by selective laser melting (SLM)

Journal of Micromechanics and Molecular Physics ◽

10.1142/s2424913020500186 ◽

2021 ◽

pp. 2050018

Author(s):

Haiyang Fan ◽

Yahui Liu ◽

Shoufeng Yang

Keyword(s):

Titanium Alloy ◽

High Temperature ◽

Titanium Alloys ◽

Selective Laser Melting ◽

Room Temperature ◽

Elevated Temperatures ◽

Aging Treatment ◽

Water Quenching ◽

Laser Melting ◽

Aging Response

Ti–6Al–2Sn–4Zr–2Mo (Ti-6242), a near-[Formula: see text] titanium alloy explicitly designed for high-temperature applications, consists of a martensitic structure after selective laser melting (SLM). However, martensite is thermally unstable and thus adverse to the long-term service at high temperatures. Hence, understanding martensite decomposition is a high priority for seeking post-heat treatment for SLMed Ti-6242. Besides, compared to the room-temperature titanium alloys like Ti–6Al–4V, aging treatment is indispensable to high-temperature near-[Formula: see text] titanium alloys so that their microstructures and mechanical properties are pre-stabilized before working at elevated temperatures. Therefore, the aging response of the material is another concern of this study. To elaborate the two concerns, SLMed Ti-6242 was first isothermally annealed at 650[Formula: see text]C and then water-quenched to room temperature, followed by standard aging at 595[Formula: see text]C. The microstructure analysis revealed a temperature-dependent martensite decomposition, which proceeded sluggishly at [Formula: see text]C despite a long duration but rapidly transformed into lamellar [Formula: see text] above the martensite transition zone (770[Formula: see text]C). As heating to [Formula: see text]C), it produced a coarse microstructure containing new martensites formed in water quenching. The subsequent mechanical testing indicated that SLM-built Ti-6242 is excellent in terms of both room- and high-temperature tensile properties, with around 1400 MPa (UTS)[Formula: see text]5% elongation and 1150 MPa (UTS)[Formula: see text]10% elongation, respectively. However, the combination of water quenching and aging embrittled the as-built material severely.

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