Growth and Deformation Simulation of Aluminum Bronze Grains Produced by Electron Beam Additive Manufacturing

When working out 3D building-up modes, it is necessary to predict the material properties of the resulting products. For this purpose, the crystallography of aluminum bronze grains after electron beam melting has been studied by EBSD analysis methods. To estimate the possibility of sample form changes by pressure treatment, we simulated structural changes by the method of molecular dynamics during deformation by compression of individual grains of established growth orientations. The analysis was carried out for free lateral faces and grain deformation in confined conditions. Simulation and experiments on single crystals with free lateral faces revealed the occurrence of stepwise deformation in different parts of the crystal and its division into deformation domains. Each domain is characterized by a shear along a certain slip system with the maximum Schmidt factor. Blocking the shear towards the lateral faces leads to selectivity of the shear along the slip systems that provide the required shape change. Based on the simulation results, the relationship between stress–strain curves and structural characteristics is traced. A higher degree of strain hardening and a higher density of defects were found upon deformation in confined conditions. The deformation of the columnar grains of the built material occurs agreed with the systems with the maximum Schmidt factor.

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Feasibility Study of the Cranial Implant Fabricated without Supports in Electron Beam Melting

Metals ◽

10.3390/met11030496 ◽

2021 ◽

Vol 11 (3) ◽

pp. 496

Author(s):

Khaja Moiduddin ◽

Syed Hammad Mian ◽

Wadea Ameen ◽

Hisham Alkhalefah ◽

Abdul Sayeed

Keyword(s):

Electron Beam ◽

Electron Beam Melting ◽

Structural Characteristics ◽

Cost Effective ◽

Medical Industry ◽

Detailed Review ◽

Build Time ◽

Cranial Implant ◽

Cranial Implants ◽

Fabrication Time

Additive manufacturing (AM), particularly electron beam melting (EBM), is becoming increasingly common in the medical industry because of its remarkable benefits. The application of personalized titanium alloy implants produced using EBM has received considerable attention in recent times due to their simplicity and efficacy. However, these tailored implants are not cost-effective, placing a tremendous strain on the patient. The use of additional materials as support during the manufacturing process is one of the key causes of its high cost. A lot of research has been done to lessen the use of supports through various types of support designs. There is indeed a noticeable paucity of studies in the literature that have examined customized implants produced without or minimal supports. This research, therefore, reports on the investigation of cranial implants fabricated with and without supports. The two personalized implants are evaluated in terms of their cost, fabrication time, and accuracy. The study showed impressive results for cranial implants manufactured without supports that cost 39% less than the implants with supports. Similarly, the implant’s (without supports) build time was 18% less than its equivalent with supports. The two implants also demonstrated similar fitting accuracy with 0.2613 mm error in the instance of implant built without supports and 0.2544 mm for the implant with supports. The results indicate that cranial implants can be produced without EBM supports, which can minimize both production time and cost substantially. However, the manufacture of other complex implants without supports needs further study. The future study also requires a detailed review of the mechanical and structural characteristics of cranial implants built without supports.

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Selective Electron Beam Melting of the Single Crystalline Nickel-Base Superalloy CMSX-4®: From Columnar Grains to a Single Crystal

10.7449/superalloys/2016/superalloys_2016_341_349 ◽

2016 ◽

Author(s):

C. Körner ◽

M. Ramsperger

Keyword(s):

Electron Beam ◽

Single Crystal ◽

Electron Beam Melting ◽

Nickel Base Superalloy ◽

Single Crystalline ◽

Selective Electron Beam Melting ◽

Columnar Grains ◽

Nickel Base ◽

Base Superalloy

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PROCESSING OF EXPERIMENTAL DATA OF THE PROCESS OF REFINING NUCLEAR MATERIAL Zr1%Nb BY ELECTRON-BEAM MELTING BY MEANS OF INTERVAL ANALYSIS METHODS

10.46813/2019-123-118 ◽

2019 ◽

pp. 118-123

Author(s):

A.V. Yefimov ◽

M.M. Pylypenko ◽

T.V. Potanina ◽

T.A. Yesypenko ◽

T.A. Harkusha ◽

...

Keyword(s):

Experimental Data ◽

Electron Beam ◽

Interval Analysis ◽

Electron Beam Melting ◽

Nuclear Material ◽

Nuclear Materials ◽

Analysis Methods ◽

The Relationship ◽

Content Of Oxygen

The possibilities of applying the methods and models of interval analysis, which take into account the uncertainties in the specification of data for Zr1%Nb alloys, to more accurately determine the relationship between the microhardness of Zr1%Nb alloy samples and the content of oxygen in them, have been investigated. The correctness of the application of methods and models of interval analysis for processing the results of experiments to study the properties of nuclear materials is shown.

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Compressive properties and micro-structural characteristics of Ti–6Al–4V fabricated by electron beam melting and selective laser melting

Materials Science and Engineering A ◽

10.1016/j.msea.2019.138204 ◽

2019 ◽

Vol 764 ◽

pp. 138204 ◽

Cited By ~ 14

Author(s):

Lijun Xiao ◽

Weidong Song ◽

Menglei Hu ◽

Peifeng Li

Keyword(s):

Electron Beam ◽

Selective Laser Melting ◽

Electron Beam Melting ◽

Structural Characteristics ◽

Compressive Properties ◽

Laser Melting

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Strength and Ductility Improvement through Thermomechanical Treatment of Wire-Feed Electron Beam Additive Manufactured Low Stacking Fault Energy (SFE) Aluminum Bronze

Metals ◽

10.3390/met10121568 ◽

2020 ◽

Vol 10 (12) ◽

pp. 1568

Author(s):

Ekaterina Khoroshko ◽

Andrey Filippov ◽

Sergei Tarasov ◽

Nikolay Shamarin ◽

Evgeny Moskvichev ◽

...

Keyword(s):

Electron Beam ◽

Strain Hardening ◽

High Strength ◽

Tensile Tests ◽

Aluminum Bronze ◽

Columnar Grains ◽

Small Grains ◽

Strength And Plasticity ◽

Wire Feed ◽

Strength And Ductility

An as-cast macrostructure of electron beam additively manufactured metallic materials was represented by coarse columnar grains whose axes were inclined at 25° with respect to the substrate’s plane. One part of the as-grown samples was annealed to form a coarse grain microstructure while the other part was pre-deformed by forging and then annealed what allowed obtaining recrystallized microstructures with small grains and multiple annealing twin boundaries. This sample showed both high strength and plasticity during the tensile tests. These tensile tests demonstrated also two-stage stress-strain curves as depended on their strain hardening rates. High and low strain hardening rates corresponded to a twinning-dominated deformation at stage II and dislocation-base deformation at stage III. A submicron size strain-induced grain-subgrain microstructure was formed in the vicinity of a necked zone as a result of combined twinning/dislocation grain refining.

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Selective electron beam melting of an aluminum bronze: Microstructure and mechanical properties

Materials Letters ◽

10.1016/j.matlet.2018.12.015 ◽

2019 ◽

Vol 238 ◽

pp. 241-244 ◽

Cited By ~ 8

Author(s):

Torsten Wolf ◽

Zongwen Fu ◽

Carolin Körner

Keyword(s):

Mechanical Properties ◽

Electron Beam ◽

Electron Beam Melting ◽

Aluminum Bronze ◽

Microstructure And Mechanical Properties ◽

Selective Electron Beam Melting

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Microstructures of Electron Beam Melted (EBM) Biomaterial Ti-6Al-4V

MRS Proceedings ◽

10.1557/proc-1132-z09-06 ◽

2008 ◽

Vol 1132 ◽

Cited By ~ 1

Author(s):

Adnan Safdar ◽

Liu-Ying Wei

Keyword(s):

Electron Beam ◽

Electron Beam Melting ◽

Layer Structure ◽

Processing Parameters ◽

Optical Microscope ◽

Solid Samples ◽

Direction Parallel ◽

Β Phase ◽

Shape Structure ◽

Columnar Grains

ABSTRACTTi-6Al-4V alloy is an attractive biomaterial. The current work evaluates the microstructures of the solid and net-shape Ti-6Al-4V alloy produced by Electron Beam Melting (EBM) system using SEM/EDX and optical microscope. The microstructures are influenced by the cooling rate, processing parameters of the EBM system and re-heating of the existing layer during the melting of subsequent layers. Layer structure and columnar grains have been observed, with growing direction parallel to the built direction. The interior of these grains consists of alternating α / β phases. The β phase in the colonies resembles rod shape embedded in the α platelet. Along the grain boundaries more or less continuous α layers were observed. In comparison to solid samples uneven surfaces and pores were seen in the net shape structure. Microhardness evaluation of the EBM produced alloys was also carried out and compared with conventionally produced alloys.

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