Production Of Titanium Powder Research Articles

A new method of patent analysis to support prospective life cycle assessment of eco-design solutions

Prospective life cycle assessment (LCA) was introduced with the goal to evaluate the environmental sustainability of eco-design solutions (i.e., ideas, prototypes, immature products, emerging technologies) prospectively rather than existing products, at the present time, as in traditional LCA. The main difference lies in the inventory, which is foreground and is based solely on the extraction of data from prospective documents, including patents, although this task, is tricky and can make the final result uncertain. This study proposes a systematic method to collect all the flows about a specific function of the product lifecycle from patent literature for building the foreground inventory of prospective LCA, ensuring comparability, data quality and scale-up. This was done by studying the intersections between patent analysis techniques and LCA requirements for reducing the uncertainty, prescribed by ISO 14040, ISO 14044, Pedigree Matrix and Data Quality Indicators for Life Cycle Inventory Data. The application of the proposed method to a case study related to the production of titanium powders using an innovative process revealed its main advantages in collecting patents and extracting data. Patent search recall and precision are increased. Patents are filtered by seeking a trade-off to ensure time consistency and avoid anomalous fluctuations in the data resulting from predatory patenting strategies. Data reliability and significance are controlled. Results can be expressed without levelling them around the average value, but adding time evolution and forecasting considerations. For example, the global warming potential (GWP) of the innovative process is 1.5 % lower than the GWP of the current process, considering the average patent data of the last 10 years. In addition, this value showed a 1 % increase for each year.

Production of Titanium Hydride Powder from Titanium Tetrachloride Using Magnesium Metal in Hydrogen Gas Atmosphere

The development of titanium (Ti) powder production process is important because Ti powder metallurgy (PM) is a promising method that can result in large cost savings by reducing material loss and the number of steps in the conventional manufacturing process of Ti metal and its alloys. This study investigated the process of producing Ti hydride powder directly from titanium tetrachloride (TiCl4) using magnesium (Mg) metal and hydrogen gas (H2). The experiments were conducted at 1073–1173 K when the TiCl4 feeding rate was in the range of 19.16–57.42 g·min−1 with the use of cooling gas as Ar or H2 gas. A mixture of Ti and Ti hydride (TiH1.5) was obtained in an iron (Fe) crucible by the dehydrogenation of Ti hydride as the TiCl4 reduction proceeded. The concentration of oxygen (O) decreased with a decrease in the specific surface area and/or an increase in the proportion of TiH1.5 in the powder. As a result, the concentration of O of the mixture of Ti and TiH1.5 decreased to 0.116 mass% under a certain condition.

Synthesis of Ti Powder from the Reduction of TiCl4 with Metal Hydrides in the H2 Atmosphere: Thermodynamic and Techno-Economic Analyses

Titanium hydride (TiH2) is one of the basic materials for titanium (Ti) powder metallurgy. A novel method was proposed to produce TiH2 from the reduction of titanium tetrachloride (TiCl4) with magnesium hydride (MgH2) in the hydrogen (H2) atmosphere. The primary approach of this process is to produce TiH2 at a low-temperature range through an efficient and energy-saving process for further titanium powder production. In this study, the thermodynamic assessment and technoeconomic analysis of the process were investigated. The results show that the formation of TiH2 is feasible at low temperatures, and the molar ratio between TiCl4 and metal hydride as a reductant material has a critical role in its formation. Moreover, it was found that the yield of TiH2 is slightly higher when CaH2 is used as a reductant agent. The calculated equilibrium composition diagrams show that when the molar ratio between TiCl4 and metal hydrides is greater than the stoichiometric amount, the TiCl3 phase also forms. With a further increase in this ratio to greater than 4, no TiH2 was formed, and TiCl3 was the dominant product. Furthermore, the technoeconomic study revealed that the highest return on investment was achieved for the production scale of 5 t/batch of Ti powder production, with a payback time of 2.54 years. The analysis shows that the application of metal hydrides for TiH2 production from TiCl4 is technically feasible and economically viable.

Production of titanium powder by metallothermic reduction of TiO2 in cold pressed pellets

In order to produce low-cost titanium (Ti) with high productivity, fundamental studies on producing metallic Ti from titanium dioxide (TiO2) in the cold pressed pellets were conducted by metallothermic reduction with an indirect contact method. This paper focuses on discussing the mechanism of the reduction process and the relationships of RM (a revised reduction index) with reduction temperature, reduction time, and mole ratio of TiO2 to CaCl2 ( $${n_{{\rm{Ti}}{{\rm{O}}_2}}}/{n_{{\rm{CaC}}{{\rm{l}}_2}}}$$ ) in the pellets. The results show that metallic Ti was obtained from the reduction of TiO2 in the pellets by calcium (Ca) vapor; pellets were reduced homogenously and Ca vapor diffused into the porous pellets by Knudsen diffusion or the mixing diffusion of molecular diffusion and Knudsen diffusion at 1273 K; RM increased with the increases of temperature and reduction time and was 96.34% when TRedu=1273 K, tRedu=6 h, and $${n_{{\rm{Ti}}{{\rm{O}}_2}}}/{n_{{\rm{CaC}}{{\rm{l}}_2}}} = 4$$ ; the reasonable nTiO2/nCaCl2 value is 3–5 for the pellets with enough strength and high RM.

The production of Titanium Powder via Hydrogen Reduction of Titanium Tetrachloride by Inductively Coupled RF plasma

In this study, the production of titanium powder via hydrogen reduction of titanium tetrachloride by inductively coupled radio frequency plasma was investigated. While titanium tetrachloride is hard to be reduced by hydrogen thermodynamically, dissociated hydrogen radical which formed from hydrogen gas passing through the plasma can react with titanium tetrachloride to form hydrochloric acid and subsequently produce titanium. The frequency of generator used in this experiment was 13.56 MHz and input power was varied. The characteristics of the powder such as powder size, size distribution, and phases were analyzed with x-ray diffractometer, field emission scanning electron microscope, energy dispersive x-ray spectrometer and transmission electron microscope. The deposited height of titanium powders, after 4 minutes reaction, were 4.004 μm and loosely attached that could be easily collected. The morphology of powders was found to be more spherical with the increase in applied input power. Most of the powders were composed of titanium and oxygen. The average diameter of powders was approximately 200 nm.

Thermodynamic Investigation of Titanium Hydride Formation from Reduction of Titanium (Ⅳ) Chloride with Magnesium Hydride in Presence of Hydrogen Atmosphere

Thermodynamic assessment and experimental investigation for formation of titanium hydride (TiH2) from reduction of titanium tetrachloride (TiCl4) with magnesium hydride (MgH2) were carried out under hydrogen atmosphere. In this method, TiH2 production at low temperature was investigated, which can be used for further dehydrogenation process in titanium powder metallurgy. The effects of temperature, time, amount of titanium trifluoride (TiF3) as catalyst, and ball milling time of MgH2 on reduction process were evaluated. The range of each parameters were set to 250-350°C for temperature, 2-4 hr for reaction time, 4-10 wt% for TiF3, and 1-2 hr for ball milling time. The phase transformations after reduction process were studied by X-ray diffraction (XRD) and energy-dispersive X-ray (EDX) analyziz. The morphology of powders was analyzed by scanning electron microscope (SEM). The results showed that titanium trichloride (TiCl3) was formed as major product in experiments for the above conditions. However, with increasing the reaction time above 10hr, characterization study of the final products confirmed the formation of TiH2 as major product. Our findings indicated that producing of TiH2 from reduction of TiCl4 with MgH2 at low temperature was feasible and could lead to low cost synthesis method for TiH2 for titanium powder production.

Production of Fine Titanium Powder from Titanium Sponge by the Shuttle of the Disproportionation Reaction in Molten NaCl–KCl

Production of Fine Titanium Powder from Titanium Sponge by the Shuttle of the Disproportionation Reaction in Molten NaCl–KCl

Formation of Titanium Sulfide from Titanium Oxycarbonitride by CS2 Gas

Previously this group reported that a good quality titanium metal powder can be produced from titanium sulfides by electrochemical OS process. In this study, the sulfurization procedure was examined to synthesize titanium sulfide from titanium oxycarbonitride by CS2 gas. The experiments were carried out in the temperature range of 1173 K to 1523 K (900 °C to 1250 °C) in a tube reactor with continuously flowing argon (Ar) as carrier gas of CS2. The formation of titanium sulfide phases from the commercial TiN, TiC, and TiO powders was studied as the initial step. Then, TiO0.02C0.13N0.85 coming from ilmenite was sulfurized to prepare single phase of titanium sulfide. The products were characterized by X-ray diffraction, and the morphology of the sulfides was rigorously investigated, and the sulfur, oxygen, and carbon contents in the products were analyzed. The process was remarkably dependent on the temperature and time. TiN and TiO0.02C0.13N0.85 powders could be fully converted to the single phase of Ti2.45S4 (Ti2+xS4) at 1473 K (1200 °C) in 3.6 ks. The maximum weight gain of TiN sample was ~ 55.3 pct indicating a full conversion of TiN to Ti2S3 phase. The carbon and oxygen contents in this sulfide prepared from the oxycarbonitride were about 1.8 wt pct C and 1.4 wt pct O, respectively. Therefore, the titanium sulfide could be a promising feedstock for the production of commercial grade titanium powder.

Novel and Emerging Routes for Titanium Powder Production - An Overview

As the adoption of components fabricated via titanium powder metallurgy (PM) techniques becomes more prevalent, and projected to increase at a substantial rate over the next decade, especially in the field of additive manufacturing (AM), there is a necessity to increase titanium powder production capacity from the current annual level of ca. 6000 tonnes per annum. At present a well-documented barrier restricting this widespread implementation, is the inherently high cost of the feedstock, an issue which to date has been neglected to some degree, at the expense of developing the individual powder metallurgy routes. The scope of this overview therefore is to provide an insight of both established and novel methods of titanium powder production, as potential opportunities to satisfy this growing demand. Particular emphasis will focus on Metalysis, a company founded to commercialize an innovative electrochemical approach for the synthesis of metals and alloys from their respective oxides, where the ability to generate titanium eloquently demonstrates the extent of its capabilities.The patented Metalysis technology, exploiting the FFC® Cambridge process, lends itself to producing alloys and intermetallics, where Ti-6Al-4V provides a prime example of this. Furthermore, as electrolysis occurs solely in the solid state, issues pertaining to segregation due to dissimilar densities and melting points are avoided. It is possible to tailor both the average particle diameter and size distribution of the product targeted powder metallurgy (PM) applications, based upon appropriate selection of the feed. The attraction of this strategy is that the steps associated with conventional metal powder synthesis are circumvented, resulting in a significant cost reduction. Moreover it has recently been revealed that titanium can be produced directly from naturally occurring ore (beach sand) and synthetic rutile, with the ensuing product presenting itself as an inexpensive and abundant feedstock for additive manufacturing (AM). This represents a paradigm shift in the availability of consumables for the 3D printing market.

Production of Titanium Powder by Sodiothermic Reduction in CaCl2 Molten Salts

A new sodiothermic reduction process of TiO2 in CaCl2 melt was proposed aimed at fine Ti powder preparation. The chemical analysis and direct potentiometric methods were used to investigate the reaction pathway of sodiothermic reduction in CaCl2 melt. The as-prepared samples were characterized by X-ray diffraction and scanning electron microscopy. It was found that when reductant of Na was added into the CaCl2 melt, Ca2+ was reduced to Ca by Na and Ca dissolved in the CaCl2 melt. The whole melt would have the reducing power with dissolved Ca. Using this melt as a reaction medium, fine and uniform Ti powder with a purity of around 99 mass pct was successfully produced at 1173 K (900 °C). In addition, as the CaCl2 melt could dissolve about 20 mol pct CaO, it was found that the molar ratio of TiO2 and CaCl2 should be 1:20 to eliminate the by-product CaO from the reaction interface within the experimental period to continue the reduction.

The TiRO™ Process for the Continuous Direct Production of Titanium Powder

The CSIRO is developing the TIRO™ process for the continuous direct production of titanium powder. The process comprises two stages. The first stage is a fluidised bed reactor (FBR) in which TiCl4 is reacted with magnesium powder to form solid magnesium chloride particles about 350 µm in diameter in which micron sized titanium particles are dispersed. The second stage is a continuous vacuum distillation operation where the titanium is separated from the magnesium chloride and sintered to form a friable “biscuit”. The biscuit comprises porous titanium spheres about 250 µm in diameter which can be liberated by very light grinding. The overall process has a throughput of 0.2 kg/h Ti, limited by the vacuum distillation unit and is being scaled up. The process has generated Ti powder with ≤0.25 wt% O and < 200 ppm Cl and meets CP2 specifications. Ring grinding the vacuum distilled product for short periods reduced the particle size, however longer grinding times caused agglomeration of the particles. Ring grinding in air resulted in a large increase in oxygen concentration

Titanium Powder from the TiRO™ Process

A new continuous process for the direct production of CP titanium powder is being developed at CSIRO. The TiRO™ process has two major steps. The first step is conducted in a fluidised bed where titanium tetrachloride and magnesium powder react to form small (1.5 µm) titanium metal particles uniformly dispersed inside larger spheroidal magnesium chloride particles with an average particle size of 350 µm. The second step involves vacuum distillation in which the magnesium chloride is removed from the titanium. During vacuum distillation the magnesium chloride is volatilised and the micron sized titanium particles come together to form partially sintered predominantly spheroidal porous particles with a similar shape to the starting particle, some which appeared to be hollow. A mechanism for their formation is proposed. The spheroidal particles are all lightly sintered together. The vacuum distilled product was very lightly ground to liberate the spheroidal particles which had an average particle size of about 200 µm. With further grinding an angular Ti powder was produced. The ground titanium was free flowing and had a tap density of 2.4 g/cm3.

The FFC Cambridge Process for Production of Low Cost Titanium and Titanium Powders

The current status and recent advancements in the use of the FFC Cambridge process for the production of low cost titanium and titanium powders is presented. This will include an overview of the process, current and future process equipment and recent results in terms of chemistry, structure and properties of powder and consolidated product. The future direction and activities for the FFC Cambridge process will also be briefly discussed.

Titanium compacts produced by the pulvimetallurgical hydride–dehydride method for biomedical applications

Titanium powder production by the hydride–dehydride method has been developed as a non-expensive process. In this work, commercially pure grade two Ti specimens were hydrogenated. The hydrided material was milled in a planetary mill. The hydrided titanium powder was dehydrided and then sieved to obtain a particle size between 37 and 125 µm in order to compare it with a commercial powder produced by chemical reduction with a particle size lower than 150 µm. Cylindrical green compacts were obtained by uniaxial pressing of the powders at 343 MPa and sintering in vacuum. The powders and the density of sintered compacts were characterized, the oxygen content was measured and in vivo tests were performed in the tibia bones of Wistar rats in order to evaluate their biocompatibility. No differences were observed between the materials which were produced either with powders obtained by the hydride–dehydride method or with commercial powders produced by chemical reduction regarding modifications in compactation, sintering and biological behaviour.

Implementing the Direct Powder Route for Titanium Mill Product: Continuous Production of CP Sheet

Major research and development efforts both in CSIRO and elsewhere aim to develop processes for commercial production of low cost titanium powder. These processes could reduce the current cost of titanium, but the major savings are expected to come by enabling powder metallurgical processes which transform these powders into products. Powder metallurgical (PM) processes (e.g. CIP/HIP) are well established for discrete components, but technologies for continuous production of “mill” product are immature. New processes will be needed for the economic manufacture of mill product (e.g. sheet and tube) from the large quantities of low-cost powder which will become available when the emerging powder production processes enter commercial production. The paper will present a process for the production of commercial purity (CP) sheet by direct rolling of powder. It is novel in that it avoids both the use of binders and densification via batch sintering. A roll compacted green sheet is rapidly heated under a controlled atmosphere before being consolidated to nominally 100% density by hot rolling. Following conventional batch annealing, strip samples exhibit properties approaching those of commercial wrought sheet of an equivalent grade. In order to achieve this, a number of key variables including powder chemistry, morphology and particle packing, the roll compaction and hot rolling parameters needed to be understood and closely controlled.

Production of Titanium Powder by the Calciothermic Reduction of Titanium Concentrates or Ore Using the Preform Reduction Process

With a view to developing a new process for the production of metallic titanium (Ti) powder, the preform reduction process (PRP) based on the calciothermic reduction of Ti concentrates or ore (TiO 2 ) was investigated in this study. A Ti feed preform was fabricated at room temperature by casting and drying a prepared slurry that constituted a mixture of Ti concentrates (upgraded ilmenite (UGI), 97.1% TiO 2 ) or Ti ore (rutile, 96.4% TiO 2 with iron (Fe) as the major impurity), flux CaCl 2 ), and binder. In some experiments, carbon (C) powder was added into the slurry for an efficient Fe removal. The fabricated feed preform was calcined at 1273 K for removing the water and binder present in the preform. During the calcination of the feed preform, some metal impurities such as Fe were removed by selective chlorination. Multiple pieces of the sintered preform were then reacted with metallic calcium (Ca) vapor at 1273 K in a stainless steel reaction vessel, and Ti oxide (TiO 2 ) in the preform was reduced to metal. After reduction, the reduced preform was subjected to a leaching process using an acetic acid solution and a hydrochloric acid solution in order to remove the by-product calcium oxide (CaO), excess reductant Ca, and other impurities in the sample. After leaching, the obtained powder was then rinsed and dried; this powder was shown to be metallic Ti with a purity of 99% up. It was experimentally demonstrated that PRP is a feasible technique to produce metallic Ti powder directly from Ti concentrates or ore.

Production of titanium powder directly from TiO 2 in CaCl 2 through an electronically mediated reaction (EMR)

Production of titanium powder directly from titanium dioxide (TiO 2) through an electronically mediated reaction (EMR) using calcium as a reductant was investigated. Feed material (TiO 2 powder or preform) and reductant (Ca–Ni alloy) were charged in electronically isolated locations in a molten calcium chloride (CaCl 2) salt at 1173 K, and the current flow through an external circuit between the feed and reductant locations was monitored during reduction of TiO 2. The voltage between feed electrode and reductant alloy was intermittently measured during the reduction experiment to monitor the reduction process. After the reduction experiment, pure titanium powder with low nickel content was obtained even though liquid Ca–Ni alloy was used as a reductant. These results demonstrate that titanium metal powder can be produced without direct physical contact between the feed and reductant. In some experimental conditions, pure titanium powder with 99.5 mass% purity was successfully obtained.

Production of Titanium Powder by Electronically Mediated Reaction (EMR)

Production of titanium powder directly from tantalum oxides (<TEX>$TiO_2$</TEX>) pellet through an electronically mediated reaction (EMR) by calciothermic reduction has been investigated. Feed material (<TEX>$TiO_2\;pellet$</TEX>) and reductant (Ca-Ni alloy) were charged into electronically isolated locations in a molten calcium chloride (<TEX>$CaCl_2$</TEX>) bath at <TEX>$950^{\circ}C$</TEX>. The current flow through an external circuit between the feed (cathode) and reductant (anode) locations was monitored during the reduction of <TEX>$TiO_2$</TEX>. The current approximately 3.2A was measured during the reaction in the external circuit connecting cathode and anode location. After the reduction experiment, pure titanium powder with low nickel content was obtained even though Ca-Ni alloy was used as a reductant. These results demonstrate that titanium powder can be produced without direct physical contact between the feed and reductant. In certain experimental conditions, pure titanium powder with approximately <TEX>$99.5\;mass\%$</TEX> purity was successfully obtained.

Titanium powder production by preform reduction process (PRP)

To develop an effective process for titanium powder production, a new preform reduction process (PRP), based on the calciothermic reduction of preform containing titanium oxide (TiO 2), was investigated. The feed preform was fabricated from slurry, which was made by mixing TiO 2 powder, flux (e.g. CaCl 2) and binder. Various types of preforms in the form of plates, spheres, or tubes were prepared using a conventional technique, and the fabricated preform was sintered at 1073 K before reduction in order to remove the binder and water. The sintered solid preform containing TiO 2 was then placed in a stainless steel container, and reacted with calcium vapor at a constant temperature ranging between 1073 and 1273 K for 6 h. Titanium powder was recovered from the reduced preform by leaching it with acid. As a result, pure titanium powder with 99 mass% purity was obtained. This process was found to be suitable for producing a homogeneous fine powder when the composition of flux and the size of the preform are controlled.

Economics of production of titanium powder by plasma rotating electrode process : J.A.Isaacs et al. (Northeastern University, USA.)

In the present paper, the use of spark plasma sintering on Ti6Al4V powder was investigated. Sintering experiments were conducted at the temperature of 1000°C for 5 min. The simultaneous effect of compaction pressures of 5, 25 and 50 MPa and heating rates of 200, 300 and 400°C/min on the structure, density, microhardness, elastic modulus and compressive strength were analyzed and ranged between 4.14 and 4.43 g/cm3, 293 and 373 HV0.05, 116 and 142 GPa, 1169 and 1414 MPa respectively. With increasing compaction pressure, the effect of an increase in grain size was observed. The obtained results show that very good mechanical properties can be achieved using spark plasma sintering at a rapid heating rate and already with the 25 MPa compaction pressure. The best results of microhardness (373 HV0.05) and compressive strength (1414 MPa) with an elastic modulus of 138 GPa were obtained by the compacts sintered under the compaction pressure of 50 MPa and at the heating rate of 300°C/min.