Wire Arc Additive and High-Temperature Subtractive Manufacturing of Ti-6Al-4V

We investigated the fabrication and finishing of wall-profile machining by wire and arc additive manufacturing (WAAM) employing plasma welding with Ti-6Al-4V wire. We fabricated and integrated a local shield and a cover for the area below the local shield to achieve higher shielding ability. The tensile strength of the fabricated object met the forging standard for Ti-6Al-4V, but elongation was about 7%. We also focused on the possibility of reducing the cutting force and increasing the efficiency of the finishing process by cutting workpieces softened by high temperature immediately after the deposition process. We investigated the cutting force and tool wear of the fabricated objects heated to 300 °C using ceramics tools. Results showed that although the cutting force was reduced at high temperature, the wear rate of the tools was high, and the increase in cutting force due to wear was significant.

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Development of an Additive Manufacturing System for the Deposition of Thermoplastics Impregnated with Carbon Fibers

Journal of Manufacturing and Materials Processing ◽

10.3390/jmmp3020035 ◽

2019 ◽

Vol 3 (2) ◽

pp. 35 ◽

Cited By ~ 1

Author(s):

Miguel Reis Silva ◽

António M. Pereira ◽

Nuno Alves ◽

Gonçalo Mateus ◽

Artur Mateus ◽

...

Keyword(s):

Tensile Strength ◽

Additive Manufacturing ◽

Carbon Fibers ◽

Low Cost ◽

Deposition Process ◽

Processing Parameters ◽

Yarn Diameter ◽

Thermoplastic Matrix ◽

Anisotropic Mechanical Properties ◽

Long Carbon Fiber

This work presents an innovative system that allows the oriented deposition of continuous fibers or long fibers, pre-impregnated or not, in a thermoplastic matrix. This system is used in an integrated way with the filamentary fusion additive manufacturing technology and allows a localized and oriented reinforcement of polymer components for advanced engineering applications at a low cost. To demonstrate the capabilities of the developed system, composite components of thermoplastic matrix (polyamide) reinforced with pre-impregnated long carbon fiber (carbon + polyamide), 1 K and 3 K, were processed and their tensile and flexural strength evaluated. It was demonstrated that the tensile strength value depends on the density of carbon fibers present in the composite, and that with the passage of 2 to 4 layers of fibers, an increase in breaking strength was obtained of about 366% and 325% for the 3 K and 1 K yarns, respectively. The increase of the fiber yarn diameter leads to higher values of tensile strength of the composite. The obtained standard deviation reveals that the deposition process gives rise to components with anisotropic mechanical properties and the need to optimize the processing parameters, especially those that lead to an increase in adhesion between deposited layers.

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Interface Behavior and Interface Tensile Strength of a Hardened Concrete Mixture with a Coarse Aggregate for Additive Manufacturing

Materials ◽

10.3390/ma13225147 ◽

2020 ◽

Vol 13 (22) ◽

pp. 5147

Author(s):

Arnošt Vespalec ◽

Josef Novák ◽

Alena Kohoutková ◽

Petr Vosynek ◽

Jan Podroužek ◽

...

Keyword(s):

Tensile Strength ◽

Additive Manufacturing ◽

Pore Size ◽

Coarse Aggregate ◽

Deposition Process ◽

Interface Strength ◽

Concrete Mixture ◽

Hardened Concrete ◽

Time Intervals ◽

Layer Interface

3D concrete printing technology (3DCP) is a relatively new technology that was first established in the 1990s. The main weakness of the technology is the interface strength between the extruded layers, which are deposited at different time intervals. Consequently, the interface strength is assumed to vary in relation to the time of concrete casting. The proposed experimental study investigated the behavior of a hardened concrete mixture containing coarse aggregates that were up to 8 mm in size, which is rather unusual for 3DCP technology. The resulting direct tensile strength at the layer interface was investigated for various time intervals of deposition from the initial mixing of concrete components. To better understand the material behavior at the layer interface area, computed tomography (CT) scanning was conducted, where the volumetric and area analysis enabled validation of the pore size and count distribution in accordance with the layer deposition process. The analyzed CT data related the macroscopic anisotropy and the resulting crack pattern to the temporal and spatial variability that is inherent to the additive manufacturing process at construction scales while providing additional insights into the porosity formation during the extrusion of the cementitious composite. The observed results contribute to previous investigations in this field by demonstrating the causal relationships, namely, how the interface strength development is determined by time, deposition process, and pore size distribution. Moreover, in regard to the printability of the proposed coarse aggregate mixture, the specific time interval is presented and its interplay with interface roughness and porosity is discussed.

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Improving the surface quality and mechanical properties of selective laser sintered PA2200 components by the vibratory surface finishing process

SN Applied Sciences ◽

10.1007/s42452-021-04371-4 ◽

2021 ◽

Vol 3 (3) ◽

Author(s):

Hamaid M. Khan ◽

Tolga B. Sirin ◽

Gurkan Tarakci ◽

Mustafa E. Bulduk ◽

Mert Coskun ◽

...

Keyword(s):

Mechanical Properties ◽

Surface Roughness ◽

Tensile Strength ◽

Additive Manufacturing ◽

Microstructural Analysis ◽

Surface Hardness ◽

Physical And Mechanical Properties ◽

Surface Finishing ◽

Finishing Process ◽

Wide Range

Abstract This paper attempts to improve the physical and mechanical properties of selective laser sintered polyamide PA2200 components through a vibratory surface finishing process by inducing severe plastic deformation at the outer surface layers. The industrial target of additive manufacturing components is to obtain structures having surface roughness, hardness, and other mechanical properties equivalent to or better than those produced conventionally. Compared to the as-built SLS PA2200 samples, vibratory surface finishing treated specimens exhibited a smooth surface microstructure and more favorable roughness, hardness, and tensile strength. Also, the duration of the vibratory surface finishing process showed a further improvement in the surface roughness and hardness of the SLS samples. Compared to the as-built state, the roughness and hardness of the surface-treated samples improved by almost 90% and 15%, respectively. Consequently, microstructural analysis indicates that lower surface roughness and enhanced surface hardness is a crucial factor in influencing the overall tensile strength of SLS-PA2200 components. We consider that the combination of VSF and SLS processes can successfully handle a wide range of potential applications. This study also highlights the efficiency and applicability of the vibratory surface finishing process to other additive manufacturing processes and materials. Graphic abstract

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VASCO 9-4-20

Alloy Digest ◽

10.31399/asm.ad.sa0489 ◽

1997 ◽

Vol 46 (10) ◽

Keyword(s):

Fracture Toughness ◽

Tensile Strength ◽

High Temperature ◽

Ultimate Tensile Strength ◽

Physical Properties ◽

Tensile Properties ◽

Heat Treating ◽

High Tensile Strength ◽

Temperature Performance

Abstract Vasco 9-4-20 (0.20 wt% C) is a premium quality aircraft steel that combines high tensile strength with good fracture toughness. It is a heat-treatable alloy capable of developing an ultimate tensile strength greater than 190 ksi. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fracture toughness. It also includes information on high temperature performance as well as heat treating, machining, and joining. Filing Code: SA-489. Producer or source: Vasco, An Allegheny Teledyne Company.

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VASCOMAX T-300

Alloy Digest ◽

10.31399/asm.ad.sa0454 ◽

1990 ◽

Vol 39 (12) ◽

Keyword(s):

Heat Treatment ◽

Fracture Toughness ◽

Tensile Strength ◽

High Temperature ◽

Heat Treating ◽

Vacuum Arc ◽

Vacuum Induction Melting ◽

Induction Melting ◽

Vacuum Arc Remelting ◽

Temperature Performance

Abstract VASCOMAX T-300 is an 18% nickel maraging steel in which titanium is the primary strengthening agent. It develops a tensile strength of about 300,000 psi with simple heat treatment. The alloy is produced by Vacuum Induction Melting/Vacuum Arc Remelting. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fracture toughness. It also includes information on high temperature performance as well as forming, heat treating, machining, and joining. Filing Code: SA-454. Producer or source: Teledyne Vasco.

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ATI 6-2-4-2

Alloy Digest ◽

10.31399/asm.ad.ti0169 ◽

2020 ◽

Vol 69 (8) ◽

Keyword(s):

Tensile Strength ◽

Titanium Alloy ◽

High Temperature ◽

Creep Strength ◽

High Strength ◽

Heat Treating ◽

Good Combination ◽

Long Term Stability ◽

Temperature Performance

Abstract ATI 6-2-4-2 is a near-alpha, high strength, titanium alloy that exhibits a good combination of tensile strength, creep strength, toughness, and long-term stability at temperatures up to 425 °C (800 °F). Silicon up to 0.1% frequently is added to improve the creep resistance of the alloy. This datasheet provides information on composition, physical properties, hardness, and tensile properties as well as creep. It also includes information on high temperature performance as well as forming, heat treating, machining, and joining. Filing Code: Ti-169. Producer or Source: ATI.

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The Influence of La and Ce on Microstructure and Mechanical Properties of an Al-Si-Cu-Mg-Fe Alloy at High Temperature

Metals ◽

10.3390/met11030384 ◽

2021 ◽

Vol 11 (3) ◽

pp. 384

Author(s):

Andong Du ◽

Anders E. W. Jarfors ◽

Jinchuan Zheng ◽

Kaikun Wang ◽

Gegang Yu

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

High Temperature ◽

Intermetallic Phases ◽

High Temperature Strength ◽

Thermal Expansion Mismatch ◽

Strengthening Mechanisms ◽

High Temperature Mechanical Properties ◽

Minor Contribution ◽

A Minor

The effect of lanthanum (La)+cerium (Ce) addition on the high-temperature strength of an aluminum (Al)–silicon (Si)–copper (Cu)–magnesium (Mg)–iron (Fe)–manganese (Mn) alloy was investigated. A great number of plate-like intermetallics, Al11(Ce, La)3- and blocky α-Al15(Fe, Mn)3Si2-precipitates, were observed. The results showed that the high-temperature mechanical properties depended strongly on the amount and morphology of the intermetallic phases formed. The precipitated tiny Al11(Ce, La)3 and α-Al15(Fe, Mn)3Si2 both contributed to the high-temperature mechanical properties, especially at 300 °C and 400 °C. The formation of coarse plate-like Al11(Ce, La)3, at the highest (Ce-La) additions, reduced the mechanical properties at (≤300) ℃ and improved the properties at 400 ℃. Analysis of the strengthening mechanisms revealed that the load-bearing mechanism was the main contributing mechanism with no contribution from thermal-expansion mismatch effects. Strain hardening had a minor contribution to the tensile strength at high-temperature.

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