Achieving high strength-ductility synergy in a novel Mg–Bi–Sn–Mn alloy with bimodal microstructure by hot extrusion

Stainless steels are important technologically for a wide range of applications. Though they are attractive for their environmental stability, austenitic versions of these steels are not generally known for their very high strength. We have rapid-solidification-processed many stainless steels by gas atomization and achieved strength improvements of over 50% relative to conventionally-processed stainless steels with concomitant improvement in corrosion and oxidation behavior. These strength improvements are most pronounced when elevated concentrations of oxygen and vanadium are present in the metal and we need to know how these elements affect precipitation in the alloy.The specimen material (FCC Fe-16%Ni-9%Cr-0.5%Mn-0.2%V-0.0137%N-0.008%O by weight) was prepared by gas atomization and hot extrusion followed by precipitation aging as described elsewhere. We observed the structure in TEM and found 20 nm precipitates on dislocations, Fig. 1a. We did not observe smaller precipitates in the grain interiors using diffraction contrast bright field imaging, however, with weak-beam dark field imaging, Moiré fringe contrast is observed throughout the material, Fig. 1b.

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The Production of Material with Ultrafine Grain Structure in Al-Zn Alloy in the Process of Rapid Solidification

Archives of Foundry Engineering ◽

10.2478/afe-2014-0037 ◽

2014 ◽

Vol 14 (2) ◽

pp. 57-62

Author(s):

M. Szymaneka ◽

B. Augustyn ◽

D. Kapinos ◽

S. Boczkal ◽

J. Nowak

Keyword(s):

Rapid Solidification ◽

Melt Spinning ◽

Hot Extrusion ◽

High Strength ◽

Strength Properties ◽

Grain Structure ◽

Ultrafine Grain ◽

Plastic Working ◽

Metal Treatment ◽

Ultrafine Grain Structure

Abstract In the aluminium alloy family, Al-Zn materials with non-standard chemical composition containing Mg and Cu are a new group of alloys, mainly owing to their high strength properties. Proper choice of alloying elements, and of the method of molten metal treatment and casting enable further shaping of the properties. One of the modern methods to produce materials with submicron structure is a method of Rapid Solidification. The ribbon cast in a melt spinning device is an intermediate product for further plastic working. Using the technique of Rapid Solidification it is not possible to directly produce a solid structural material of the required shape and length. Therefore, the ribbon of an ultrafine grain or nanometric structure must be subjected to the operations of fragmentation, compaction, consolidation and hot extrusion. In this article the authors focussed their attention on the technological aspect of the above mentioned process and described successive stages of the fabrication of an AlZn9Mg2.5Cu1.8 alloy of ultrafine grain structure designated for further plastic working, which enables making extruded rods or elements shaped by the die forging technology. Studies described in the article were performed under variable parameters determined experimentally in the course of the alloy manufacturing process, including casting by RS and subsequent fragmentation.

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Bimodal-grained high-strength nickel-base ODS alloy fabricated by mechanical alloying and hot extrusion

Materials Today Communications ◽

10.1016/j.mtcomm.2020.101921 ◽

2021 ◽

Vol 26 ◽

pp. 101921

Author(s):

Wuqiang He ◽

Feng Liu ◽

Liming Tan ◽

Lan Huang ◽

Yan Nie ◽

...

Keyword(s):

Mechanical Alloying ◽

Hot Extrusion ◽

High Strength ◽

Nickel Base ◽

Ods Alloy

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Lightweight in Automotive Components by Forming Technology

Automotive Innovation ◽

10.1007/s42154-020-00103-3 ◽

2020 ◽

Vol 3 (3) ◽

pp. 195-209 ◽

Cited By ~ 4

Author(s):

Stephan Rosenthal ◽

Fabian Maaß ◽

Mike Kamaliev ◽

Marlon Hahn ◽

Soeren Gies ◽

...

Keyword(s):

High Performance ◽

Lightweight Design ◽

Dissimilar Materials ◽

Hot Extrusion ◽

High Strength ◽

Extrusion Process ◽

Specific Strength ◽

Metal Metal ◽

Fiber Metal ◽

Strength And Stiffness

AbstractLightweight design is one of the current key drivers to reduce the energy consumption of vehicles. Design methodologies for lightweight components, strategies utilizing materials with favorable specific properties and hybrid materials are used to increase the performance of parts for automotive applications. In this paper, various forming processes to produce light parts are described. Material lightweight design is discussed, covering the manufacturing processes to produce hybrid components like fiber–metal, polymer–metal and metal–metal composites, which can be used in subsequent deep drawing or combined forming processes. Approaches to increasing the specific strength and stiffness with thermomechanical forming processes as well as the in situ control of the microstructure of such components are presented. Structure lightweight design discusses possibilities to plastically form high-strength or high-performance materials like magnesium or titanium in sheet, profile and tube forming operations. To join those materials and/or dissimilar materials, new joining by forming technologies are shown. To economically produce lightweight parts with gears or functional elements, incremental sheet-bulk metal forming is presented. As an important part property, the damage evolution during the forming operations will be discussed to enable even lighter parts through a more reliable design. New methods for predicting and tailoring the mechanical properties like strength and residual stresses will be shown. The possibilities of system lightweight design with forming technologies are presented. A combination of additive manufacturing and forming to produce highly complex parts with integrated functions will be shown. The integration of functions by a hot extrusion process for the manufacturing of shape memory alloys is presented. An in-depth understanding of the newly developed processes, methodologies and effects allows for a more accurate dimensioning of components. This facilitates a reduction in the total mass and an increasing performance of vehicle components.

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Influence of ECAP Routes on the Microstructure and Mechanical Properties of Hot Extruded 3003 Al Alloy

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.124-126.1397 ◽

2007 ◽

Vol 124-126 ◽

pp. 1397-1400 ◽

Cited By ~ 2

Author(s):

Byoung Soo Lee ◽

Hoon Cho

Keyword(s):

Mechanical Properties ◽

Grain Refinement ◽

Hot Extrusion ◽

High Strength ◽

Al Alloy ◽

Deformation Structure ◽

Ecap Processing ◽

Fine Grained ◽

Strain Process ◽

Equiaxed Grains

The microstructures and mechanical properties of unidirectional deformation structured Al alloy during ECAP with various deformation routes were investigated. In order to fabricate unidirectional deformation structure for Al alloy, hot extrusion was carried out. It was found that the deformation route A in ECAP routes is the dominant route for the grain refinement and strengthening. In deformation route A, the high strength ultra-fine grained Al alloy with a grain size of ~ 200 nm was obtained due to the accumulation of consecutive strain process. In contrast, the strength of ECAP’ed Al alloy produced via deformation route C was greatly increased after one pass because the grains were strained and cancelled each pass. By contrast, the equiaxed grains were obtained in deformation route BC because the sample was rotated 90 O in the same sense in each pass. The deformation route BC was superior to the deformation route C because the deformation route BC was more favorable than the deformation route C in the accumulation of consecutive strain. It is also found that unidirectional deformation structured Al alloy via hot extrusion shows similar grain refinement tendency with equiaxed structured Al alloy during ECAP processing.

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Fabrication of extraordinary high-strength magnesium alloy by hot extrusion

Scripta Materialia ◽

10.1016/j.scriptamat.2009.06.003 ◽

2009 ◽

Vol 61 (6) ◽

pp. 644-647 ◽

Cited By ~ 344

Author(s):

T. Homma ◽

N. Kunito ◽

S. Kamado

Keyword(s):

Magnesium Alloy ◽

Hot Extrusion ◽

High Strength

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Green and Sintered Properties of Consolidated Mixtures of Mechanically Alloyed and Elemental Al Powders

Materials Science Forum ◽

10.4028/www.scientific.net/msf.514-516.774 ◽

2006 ◽

Vol 514-516 ◽

pp. 774-778 ◽

Cited By ~ 3

Author(s):

José A. Rodríguez ◽

José M. Gallardo ◽

Enrique J. Herrera

Keyword(s):

Sinter Process ◽

Hot Extrusion ◽

Bimodal Microstructure ◽

Mechanically Alloyed ◽

Al Powder ◽

The University ◽

Alloyed Aluminium ◽

Strength And Ductility

Mechanically alloyed aluminium, MA Al, powder is difficult to consolidate. Consolidation often involves complex processing that includes a hot extrusion stage. An alternative consolidation method consisting of a press-and-sinter process has been developed at the University of Seville. Nevertheless, sintered MA Al compacts have a low ductility. In the present work, to improve the ductility of consolidated compacts, hard MA Al powder was blended prior to the consolidation processing with different amounts (10, 20, 30 wt%) of soft unmilled Al powder. The bimodal microstructure (hard/soft) of the final compacts makes it possible to balance strength and ductility values.

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Development of High Strength Alloys in the Mg-Ni-Y-RE System

Materials Science Forum ◽

10.4028/www.scientific.net/msf.567-568.385 ◽

2007 ◽

Vol 567-568 ◽

pp. 385-388 ◽

Cited By ~ 18

Author(s):

P. Pérez ◽

S. González ◽

G. Garcés ◽

G. Caruana ◽

P. Adeva

Keyword(s):

Magnesium Alloy ◽

Load Transfer ◽

Volume Fraction ◽

Hot Extrusion ◽

High Strength ◽

High Volume ◽

Magnesium Matrix ◽

Fine Grained ◽

Matrix Embedding ◽

Second Phases

The microstructural and mechanical characterization of two alloys within the Mg-Ni-YRE system prepared by casting and subsequent hot extrusion at 400°C have been carried out. The microstructure of both materials consists of a fine-grained magnesium matrix embedding a high volume fraction of second phases; coarse Mg12RE and long period ordered stacking structure (LPS phase) and fine Mg2Ni particles. Both alloys show high strength values up to 250°C. The yield stress values at room temperature are 295 and 405 MPa for low- and high-alloyed magnesium alloy, respectively. Load transfer from the magnesium matrix to coarse Mg12RE and LPS particles account for the high strength of both alloys at temperatures below 250°C. Above this temperature both alloys exhibit a superplastic behaviour at low stresses with elongations of 700 and 450 % for the low and high-alloyed magnesium alloy, respectively.

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