scholarly journals Production of spherical titanium alloy powders used in additive manufacturing from titanium scrap

2020 ◽  
Vol 321 ◽  
pp. 07008
Author(s):  
Taras Yanko ◽  
Viktor Brener ◽  
Olexandr Ovchinnikov

The main materials for 3D printing of titanium are fine metal alloy powders from which produce final articles with required quality. These powders must have definite chemical compositions, physical/mechanical characteristics, and also necessary operational properties. Key parameters of titanium alloy powders are homogeneity of chemical compositions, microstructures as well as flow ability. Conventional atomisation methods for metal powders like GA, PREP, PA, etc, are complicated and sufficiently expensive. Alternative production route is usage of complex processing technology of titanium alloy scrap as initial raw material. Spheriodised powder manufacturing scheme which includes raw material preparation, preliminary and final treatments have been presented. At the first step titanium scrap was divided according to titanium alloy types, purified from contaminants and oxide films. Then prepared materials were converted to non-spherical powders with definite fractional compositions using hydrogenation/de-hydrogenation (HDH) method. Experimental HDH equipment allows close cycle of hydrogen recovery almost without losses. Obtained non-spherical powders were treated in the plasma unit yielding spherical titanium alloy. Offered technical solutions permit production of raw materials for 3D printing from scrap with high actual yield of required fractional compositions.

2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Darfizzi Derawi ◽  
Bashar Mudhaffar Abdullah ◽  
Hasniza Zaman Huri ◽  
Rahimi M. Yusop ◽  
Jumat Salimon ◽  
...  

Palm olein (POo) is widely produced as edible oil in tropical countries. POois considered as renewable raw material for the new industrial and pharmaceutical products synthesis based on its characterization. Palm olein was good on its viscosity index, oxidative stability, and flash and fire point. POocontained unsaturated triacylglycerols (TAGs): POO (33.3%); POP (29.6%) which plays an important role in chemical modification process to produce new industrial products. The double bond was detected on1H-NMR (5.3 ppm) and13C-NMR (130 ppm) spectra. The chemical compositions of POowere tested by using high performance liquid chromatography (HPLC) and gas chromatography (GC) techniques. This unsaturated oil is potentially to be used as renewable raw materials in chemical modification process to synthesise polyols, polyurethane, and biolubricant for industrial and pharmaceutical products application.


2006 ◽  
Vol 116-117 ◽  
pp. 565-568
Author(s):  
Eugênio José Zoqui ◽  
Marcelo Paes ◽  
Maria Helena Robert

Different techniques used to produce semi-solid alloys can result in different structures in the material and, therefore, in distinct rheological behaviours which determine its thixo-forming ability. Suitable raw materials to be used for SSM forming must present non-dendritic, very fine or fragmented structure in order to globularize without excessive agglomeration when re-heated to the semi-solid state. This work analyses the influence of raw material production route on the rheological behaviour of semi-solid A356 alloy. Techniques used were: electromagnetic stirring (EMS) and chemical ultra-refining (UR). Samples were re-heated to 580oC (~ 0.45 solid fraction) and hold for 0, 90 and 210s to allow the observation of the structure evolution. After structures characterization, the samples were submitted to compression tests, at δH/δt = 10mm/s, in the same temperature/holding time conditions. Viscosity of the differently prepared raw material was related to the grain size, primary particle size, geometrical factor (roundness shape factor and contiguity).


2020 ◽  
Vol 321 ◽  
pp. 07001
Author(s):  
Simon J. Graham ◽  
Lyndsey L. Benson ◽  
Martin Jackson

Utilising novel extraction and processing technologies allows for the realisation of an alternative titanium alloy production route, with many benefits over the traditional Kroll-based one. The route proposed has the potential to reduce the cost of titanium and offers the ability to create alloys which are difficult to make conventionally. It combines the Metalysis Process, an electrolytic metal extraction technique, with field assisted sintering technology (FAST), a rapid and effective solid-state sintering technique. The Metalysis Process reduces metal oxide powders directly into metal powders, which can then be consolidated using FAST. Using synthetic rutile (SR) as the feedstock, compared to pigment grade rutile and TiCl4, further reduces the cost of titanium produced via this route. This research investigates the use of this route to create a range of pseudo-binary Ti-Fe alloys, by co-reducing SR with iron (III) oxide (Fe O ). Various techniques were used to analyse the feedstock, reduced alloy powders and consolidated material post-FAST to 23 determine chemistry and microstructure.


Author(s):  
S. L. Rovin ◽  
L. E. Rovin ◽  
V. A. Jaranov

In the production of mineral raw materials in cupolas, as a by-product and harmful product, a significant amount of cast iron (up to 3 % of the raw material) is formed and, as a rule, thrown into the dumps. The article presents technical solutions that ensure the separation of mineral melt and cast iron. In addition, the article describes the results of optimizing the design of ladders used for draining liquid metal from the mineral wool cupola and transporting it. The resulting cast iron ingots can then be used as a charge in the smelting of branded cast alloys.


2013 ◽  
Vol 743-744 ◽  
pp. 171-174 ◽  
Author(s):  
Ya Li Wang ◽  
Shi Jie Dong ◽  
Lin Lin Liu ◽  
Su Ping Cui

Calcium carbide Slag is from CaC2 hydrolysis reaction and will do harm to land and make pollution. Calcium carbide slag can be a substitute for limestone to produce clinker with a high portion of CaO as an excellent calcium raw material. As a kind of industrial wastes, the properties of calcium carbide slag differentiate from that of natural limestone. In the present investigation, the modern analysis methods of XRF, XRD, DTA/TG, petrographic analysis were used to compare carbide slag and limestone, and the results showed that the main chemical compositions of the calcium carbide slag were basically the same with that of natural limestone. Comparing with limestone materials, calcium carbide slag had a higher content of CaO, and the main mineral phase constituent of limestone was CaCO3, whereas the main mineral of calcium carbide slag was Ca (OH)2 with a lower decomposition temperature. It has been found that under the same temperature the amount of C3S in the clinker of calcium carbide slag batching was slightly less than that of limestone batching.


Recycling ◽  
2021 ◽  
Vol 6 (3) ◽  
pp. 60
Author(s):  
Qaisar Munir ◽  
Timo Kärki

The utilization of geopolymer 3D printing for construction products in recent years has been exceptionally substantial, owing to their low carbon dioxide emissions, high-performance properties such as durability, and good thermal and mechanical properties. This automated manufacturing process reduces the need for additional formworks, capital investments, and human resources. Geopolymer 3D printing development is emerging because of its advanced use in construction applications. However, high costs of the initial stages of geopolymer production and 3D printing has inhibited the development of this technology in many countries. This research presents a comprehensive economic evaluation of the investment for each principal stage that facilitates a better deployment of the resources. The study investigated all phases of geopolymer production, from the extraction of raw materials to printing. The cost for the four fundamental stages, namely raw material availability and transportation, pretreatments for raw materials, parameter selection and strength requirements, and printing in factories and on construction sites, were analyzed. The results show that 3D printing of a geopolymer on a construction site is economically more advantageous compared to printing in the factory. The study also verified that raw material transportation cost has the least effect on the finished product cost, whereas pretreatments of raw material and mixing parameters significantly influenced the ultimate cost of the product. Finally, research work suggested the need for future tasks to make geopolymer 3D printing a viable construction approach.


Coatings ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 390
Author(s):  
Eda Hazal Tümer ◽  
Husnu Yildirim Erbil

Polylactic acid (PLA) is the most widely used raw material in extrusion-based three-dimensional (3D) printing (fused deposition modeling, FDM approach) in many areas since it is biodegradable and environmentally friendly, however its utilization is limited due to some of its disadvantages such as mechanical weakness, water solubility rate, etc. FDM is a simple and more cost-effective fabrication process compared to other 3D printing techniques. Unfortunately, there are deficiencies of the FDM approach, such as mechanical weakness of the FDM parts compared to the parts produced by the conventional injection and compression molding methods. Preparation of PLA composites with suitable additives is the most useful technique to improve the properties of the 3D-printed PLA parts obtained by the FDM method. In the last decade, newly developed PLA composites find large usage areas both in academic and industrial circles. This review focuses on the chemistry and properties of pure PLA and also the preparation methods of the PLA composites which will be used as a raw material in 3D printers. The main drawbacks of the pure PLA filaments and the necessity for the preparation of PLA composites which will be employed in the FDM-based 3D printing applications is also discussed in the first part. The current methods to obtain PLA composites as raw materials to be used as filaments in the extrusion-based 3D printing are given in the second part. The applications of the novel PLA composites by utilizing the FDM-based 3D printing technology in the fields of biomedical, tissue engineering, human bone repair, antibacterial, bioprinting, electrical conductivity, electromagnetic, sensor, battery, automotive, aviation, four-dimensional (4D) printing, smart textile, environmental, and luminescence applications are presented and critically discussed in the third part of this review.


Author(s):  
Kantemirov Valerii ◽  
Titov Roman ◽  
Iakovlev Andrei ◽  
Kozlova Maria

Introduction. Currently, the main raw material for obtaining transparent quartz glass, an indispensable component in the production of single-crystal silicon, is high-purity quartz concentrate. The concentrate is a product of grinding natural “pure” quartz, which has undergone a cycle of mechanical and deep chemical refining, with a particle size of 0.1–0.3 mm and a total impurity content of no more than 20–30 ppm. However, in nature, deposits of pure quartz are quite rare, and it means that each explored site is of particular importance and is to be developed with minimal losses of quartz raw materials. Research aim is to develop technical solutions for processing small veins of high-purity granulated quartz. Methodology. Physical and mechanical properties and mining conditions for the individual quartz veins of the Kyshtym deposit are analyzed. Production cycle solutions for opencasting quartz veins have been developed allowing to reduce the degree of quartz over-grinding. Results. Granulated quartz, due to its structure, has the property of “avalanche” destruction into small grains. This significantly reduces the yield of the conditioned fraction –400 +20 mm, and regarding small reserves of quartz in veins, on average 0.1–2 thousand tons, it raises the question as to whether the development is feasible and effective. To increase the yield of conditioned fractions of quartz raw materials, a non-explosive technology of quartz breaking is proposed with a hydraulic hammer on a hydraulic excavator in combination with quartz vein preliminary exposure from the host rocks using a special technology for blasting rocks in the contact zone of “quartz-rock”. Conclusions. The proposed technical solutions will allow to involve small quartz veins of high purity granulated quartz into the development and provide high productivity and efficiency of mining operations without significant losses of scarce raw materials.


2019 ◽  
Vol 80 (1) ◽  
pp. 45-61
Author(s):  
Zeljko Cvetkovic ◽  
Pavle Tancic

Five typical bauxite samples from three ore deposits from the wider area of Grebnik Mt. (Metohija, Serbia) were examined with the optical microscopic, X-ray powder diffraction (XRPD) and chemical methods. The occurrences in bauxites were studied and described and the presence of major minerals was determined: diaspore, boehmite and hematite; minor minerals: quartz, goethite, rutile, kaolinite and hydro-hematite; as well as anatase, brookite, magnetite and chromite, which occur only sporadically. According to the quantity of main Al-bearers, three types of bauxite ore were recognized: diaspore, boehmite and boehmite-diaspore. Unit cell dimensions of major minerals were determined, mostly with values within reference data. However, all of the studied hematites have smaller a0 and V0 values, most probably due to the substitution of Fe3+ by Al3+. All samples are further classified as iron-rich and ferritic bauxites. It was found that there were changes in origin conditions between major Al-hydroxides minerals and hematite, as well as between the diaspore and boehmite. Determined chemical compositions put this raw material into high-quality raw materials for obtaining the electro corundum and alumina. The synthesis of the obtained data indicate that Grebnik?s bauxites have some unique characteristics, more or less different from most of the World?s known bauxite ore deposits.


2019 ◽  
Vol 23 (7) ◽  
pp. 31-35
Author(s):  
M.S. Saydumov ◽  
S.-A.Y. Murtazaev ◽  
A.Kh. Alaskhanov ◽  
I.S. Dagin ◽  
M.R. Nakhayev

The results of tests of secondary construction materials derived from man-made materials are presented. The granulometric and chemical compositions of secondary products from technogenic raw materials are investigated. The analysis of local natural and man-made raw materials base of the Chechen Republic. The possibilities of using local natural raw materials (crushed stone from gravel, natural sand, gravel, gypsum, cement, etc.) in the technology of building composite materials are shown. The suitability and efficiency of the use of technogenic raw materials in concrete and mortar technology, justified by the complex economic and environmental effect of its use in the practice of building materials science, have been experimentally proved. It has been established that with the introduction of advanced innovations in the field of concrete science it is possible to produce competitive products that are not inferior to foreign analogues.


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