Near Net Shaping of Mechanically alloyed Fe-48at%Cr Powder by Pulsed Current Sintering Process.

In spite of the difficult sinterability of Zr and Hf borides and carbides, recent results highlight that these ceramics can be produced with full density, fine microstructure, and controlled mechanical and thermal properties, through different procedures: pressureless sintering and hot pressing with proper sintering aids, reactive synthesis/sintering procedures starting from precursors, and field assisted technologies like spark plasma sintering. More recently, the use of near net shaping techniques and the development of UHTC porous components open the way to further and innovative applications, where the performances, fixed the material, are linked to 2D or 3D architectures and the high ratio of specific surface area to volume of the component and to the features of the porosity itself. Structural lightweight parts, insulator panels, filters, radiant burners, and solar absorbers are some of the possible applications.

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Carbon Powder as Additive in Near-Net-Shaping of Mechanical Components through Warm Forming Route

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.594-595.948 ◽

2013 ◽

Vol 594-595 ◽

pp. 948-952

Author(s):

Mujibur M. Rahman ◽

N.A.A.A. Kadir

Keyword(s):

Carbon Content ◽

Density Measurement ◽

Warm Forming ◽

Design Parameters ◽

Carbon Powder ◽

Forming Temperature ◽

Die Compaction ◽

Mechanical Components ◽

Near Net Shaping ◽

Net Shaping

This paper presents the study of carbon powder as additive in near-net-shaping of mechanical components through warm forming route. Three design parameters, i.e., carbon content (wt %), forming temperature, and sintering schedule were investigated. Iron powder ASC 100.29 was mechanically mixed with different wt% of carbon and copper powder for 30 minutes to prepare the feedstock. Green compacts were then formed through uni-axial die compaction process at 30°C and 180oC. The defect-free green compacts were then sintered at 1000oC in an argon gas fired furnace at a heating/cooling rate of 5oC/minute for 30, 60, and 90 minutes, respectively. The green samples as well the sintered products were characterized through relative density measurement, radial shrinkage, and microstructure evaluation. The results revealed that excessive carbon content contributed adverse effect to the final quality of the products.

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Hot Isostatic Pressing of Ti6Al4V Alloys Monolithic Bladed Disks

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.496-500.279 ◽

2014 ◽

Vol 496-500 ◽

pp. 279-283 ◽

Cited By ~ 1

Author(s):

Peng Ju Xue ◽

Yan Wu ◽

Qing Song Wei ◽

Yu Sheng Shi

Keyword(s):

Tensile Strength ◽

Hot Isostatic Pressing ◽

Fracture Morphology ◽

Bladed Disks ◽

Isostatic Pressing ◽

Bladed Disk ◽

Near Net Shape ◽

Near Net Shaping ◽

Net Shaping ◽

Parts Manufacturing

Near-net-shaping hot isostatic pressing (NNS-HIP) method was used for once-forming complex monolithic Ti6Al4V alloy bladed disks manufacturing. The complex monolithic bladed disks were formed successfully in a near-net-shape manner using the proposed HIP mold scheme in this study. The results showed that there were fine and homogeneous strip α+β phases and no obvious pores or cracks were detected. A "layered" phenomenon was observed in as-built part microstructure. The tensile strength value of specimens from the NNS-HIP bladed disks in the same furnace reached 900MPa, which was higher than the values of parts manufactured using casting and forging processes. The fracture morphology analysis showed that the sample had a ductile fracture. This study provides a reference to the NNS-HIP for the bladed disk parts manufacturing.

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Analysis of a Thixo-Lateral Forged Spindle from LTT C45, LTT C38 and LTT 100Cr6 Steel Grades

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.217-218.347 ◽

2014 ◽

Vol 217-218 ◽

pp. 347-354 ◽

Cited By ~ 7

Author(s):

Jokin Lozares ◽

Zigor Azpilgain ◽

Iñaki Hurtado ◽

Iñigo Loizaga

Keyword(s):

Mechanical Properties ◽

Current Trend ◽

Research Work ◽

Raw Material ◽

Key Factor ◽

Steel Grades ◽

Near Net Shape ◽

Net Shape Forming ◽

Near Net Shaping ◽

Net Shaping

Due to the current trend in prices of raw material and their sources, near net shaping of mechanical components will become a key factor for the companies to get the desired competitiveness. Semisolid metal (SSM) forming is one of those near net shape forming techniques revealing a high potential to reduce material as well as energy consumption compared to conventional process technologies. Thus, the aim of this research work is to demonstrate the above by manufacturing a steel commercial automotive spindle by thixo-lateral forming from three different steel grades. The starting material, the microstructure and mechanical properties are analysed along the article. Material savings of 20% have been reported together with a substantial decrease of the forming forces. In addition, great mechanical properties have been achieved which brings the process closer to the desired final industrial application.

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Freeze casting for near-net-shaping of dense zirconium diboride ceramics

Journal of the American Ceramic Society ◽

10.1111/jace.15451 ◽

2018 ◽

Vol 101 (7) ◽

pp. 2770-2785 ◽

Cited By ~ 2

Author(s):

Silvia Leo ◽

Laura Jukes ◽

Samuel Pinches ◽

Carolina Tallon ◽

George V. Franks

Keyword(s):

Zirconium Diboride ◽

Freeze Casting ◽

Near Net Shaping ◽

Net Shaping

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Near Solidus Forming (NSF): Semi-Solid Steel Forming at High Solid Content to Obtain As-Forged Properties

Metals ◽

10.3390/met10020198 ◽

2020 ◽

Vol 10 (2) ◽

pp. 198 ◽

Cited By ~ 2

Author(s):

Jokin Lozares ◽

Gorka Plata ◽

Iñaki Hurtado ◽

Andrea Sánchez ◽

Iñigo Loizaga

Keyword(s):

Hot Forging ◽

Single Step ◽

Solid Content ◽

Raw Material ◽

High Solid Content ◽

Commercial Steel ◽

Near Net Shaping ◽

Semi Solid ◽

Net Shaping ◽

Work Done

Near solidus forming (NSF) of steels is a novel process under the umbrella of semi-solid forming technologies midway between classical hot forging and semi-solid technologies. This article presents the work done at Mondragon Unibertsitatea to develop this technology and demonstrates the great potential of the NSF process. The study proves the capability of the process to reduce raw material consumption by 20%, reduce forming loads from 2100 t to 300 t, and reduce forming steps from three to one, to obtain as-forged mechanical properties, as well as the excellent repeatability of the process. The work demonstrates that manufacturing commercial steel components in a single step using several off-the-shelf alloys is possible thanks to the flowing pattern of the material, which enables near-net shaping. In the first part of the article, a general overview of the semi-automated near solidus forming cell, together with a description of the NSF manufacturing trials, is provided, followed by the presentation and discussion of the results for the selected steel alloys.

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