The TEMPER and Free Form Titanium Fabrication Initiatives at … · 2018-04-14 · CAMP...

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The TEMPER and Free Form Titanium Fabrication Initiatives

at The Center for Advanced Mineral and Metallurgical

Processing, USA

ByC. G. ANDERSON, P. J. MIRANDA,

and L. G. TWIDWELL

CAMP

The Center for Advanced Mineral and Metallurgical Processing

Montana Tech of the University of Montana

World Renowned 100+ Year Old Mineral Science and Engineering

Institution.

Currently 2,400 students enrolled.

Complete School of Mines and Engineering.

CAMP

Montana

2

3

1

4

• Northwestern USA on Canada/US

Border

• Fourth largest state

Montana

CAMP

Montana Tech of the University of Montana

View from Montana Tech Campus

CAMP

The Center for Advanced Mineral The Center for Advanced Mineral and Metallurgical Processingand Metallurgical Processing

The Center for Advanced Mineral and Metallurgical Processing will facilitate

cooperation between the university system and industry to enhance the economy of the State of Montana by supporting, developing and adding

value to the global mineral and materials industry. Economic enhancement may be

encouraged through added value processing of minerals, materials & metallurgical wastes and

developing processes that minimize waste generation.

CAMP


Started in 1989 as a Montana State Center of Excellence

Last remaining Center of its kind in Montana.

The Center is self sustaining and not directly supported.

The Center has a focus on industrial projects.

The Center is governed by a Board.

CAMP


CAMP Board of GovernorsCAMP Board of Governors

Stillwater Mining CompanyStillwater Mining CompanyPlacer Dome Placer Dome -- Golden SunlightGolden Sunlight

Advanced Silicon Materials IncorporatedAdvanced Silicon Materials IncorporatedAtlantic Richfield CompanyAtlantic Richfield Company

Summit Valley Equipment and EngineeringSummit Valley Equipment and EngineeringKennametal CorporationKennametal Corporation

Interactive Technology GroupInteractive Technology GroupGovernor of Montana’s Office Governor of Montana’s Office

Montana Tech and U of Montana FacultyMontana Tech and U of Montana Faculty

CAMP

A Process Engineering, Consulting, and Testing Facility CoA Process Engineering, Consulting, and Testing Facility Conducting nducting Applied Projects With Industrial Clients Throughout the World Applied Projects With Industrial Clients Throughout the World Providing Testing, Design, Consulting and Feasibility Studies FoProviding Testing, Design, Consulting and Feasibility Studies For:r:

Mineral Processing & Hydrometallurgical Applications • MaterialsMineral Processing & Hydrometallurgical Applications • Materials ••Precious Metal Recovery & Refining Technologies • Nickel/Cobalt Precious Metal Recovery & Refining Technologies • Nickel/Cobalt Applications & Technologies • Arsenic/Antimony Applications & Applications & Technologies • Arsenic/Antimony Applications &

Technologies • Pressure Leaching Applications • Copper Leaching,Technologies • Pressure Leaching Applications • Copper Leaching,SX, EW Applications & Technologies • Process Simulation and SX, EW Applications & Technologies • Process Simulation and

Modeling • Pyrometallurgical Applications • XModeling • Pyrometallurgical Applications • X--Ray Ray Diffraction/Scanning Electron Microscopy • Resource Recovery • Diffraction/Scanning Electron Microscopy • Resource Recovery • Wastewater Remediation • Fire Assay Wastewater Remediation • Fire Assay Automated SEM Phase Automated SEM Phase

Quantification Quantification

Only Research Capability for this in entire Western HemisphereOnly Research Capability for this in entire Western Hemisphere

The Center for Advanced Mineral The Center for Advanced Mineral and Metallurgicaland Metallurgical ProcessingProcessing

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Titanium IntroductionAerospace represents 65% of titanium market, therefore, the industry is cyclic.For non-aerospace usage, titanium must compete economically with other metals such as steel or aluminum.1-10-100 Charles River Rule (non-aerospace):$1.00 decrease in cost coupled with 10% mill reduction=100% gain in market volume.

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Titanium Information

Kroll process is still the baseline technology used for formation of elemental titanium.Fabrication of titanium significantly raises cost of finished part.However, powder metallurgy techniques of titanium may drastically reduce cost of finished parts up to 50%

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DOD Initiatives

Montana Tech and The Center for Advanced Mineral and Metallurgical Processing currently have two federal initiatives for titanium research.#1 Titanium Extraction, Mining, and Process Engineering (TEMPER) - ARDEC#2 Free Form Titanium Fabrication (FFTF) - ARL

CAMP

TEMPER Objectives

Titanium Bearing Ore Types and Availability Titanium Ore Physical Beneficiation Processes Titanium Ore Chemical Beneficiation Processes

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TEMPER Objectives

Review of the Kroll Process for Producing TitaniumConducting reviews and defining requirements for Potentially New Emerging Titanium Production Processes

CAMP

Free Form Titanium Fabrication Objectives

Establishing, Reviewing and Optimizing Titanium Mill Product Fabrication ProcessesReduce Overall Fabricated Cost– From $15 -$20 to $4 -$6 per pound

Increase overall supply by use of titanium scrap metal usage

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Titanium Process Steps and Resultant Costs

Titanium Processing Steps and Resultant CostsKroll

TiO2 TiCl4

TiCl4

Ti Metal

Sponge

Sponge andScrap

Ti Metal and Scrap

Vacuum Melt

VacuumRemelt

PlasmaMelt

Plasma Melt

Aerospace Grade Product$15-20/lb Plate

Non-aerospace Grade Product$11/lb Plate

Alterate non-aerospace Grade Product$11/lb Plate

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Titanium Cyclic ProductionTitanium Cyclic Production

00

2525

5050

7575

100100

125125

150150

175175

19701970 19731973 19761976 19791979 19821982 19851985 19881988 19911991 19941994 19971997 20002000

7 years7 years8 years8 years

8 years8 years

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Titanium Metal Processes

Kroll MethodFCC/TIMET Process– Reduction of Rutile in molten salt bath

Selected by US Defense Advanced Research Project Agency (DARPA)– Requires high purity source of rutile

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Armstrong International– Liquid sodium reduction of TiCl4

Successful pilot plant workParticle size experimental work being completed along with continuous reactor.

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MER Process– Anode reduction of TiO2 in mixed halide molten

salt solutionDARPA ContractPilot plant process to be evaluated

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SRI International– Fluidized bed reduction onto metal substrates.– Cheaper than Kroll Process.– Contains less oxygen and chloride.– Final product contains hydrides.

Pilot studies to be performed.

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OS Process Kyoto University– Calciothermic reduction in calcium chloride

electrolyte solution– Oxygen contents of <100 ppm possible

Present status unknown

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MER Chem and University of Bremen– Iodine reduction of TiO2 in shaking reactor– Removal of iodine from titanium tetraiodide

Pilot demonstrations must be performed

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Quebec Rio Tinto– Electrolytic conversion of titania slags into

elemental titanium.– Process involves pouring molten slag into

electric arc furnace.– Two stage electrolysis

Removal of impurities followed by titanium collection

Status Unknown

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University of Tokyo Reduction– Reduction of TiO2 by calcium vapors.– Expensive process due to cost of elemental

calcium.Status Unknown.

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Idaho Research.– Mechanochemical reduction– Reduction of TiCl4 by magnesium, calcium or

hydrides in a ball mill.– Produces titanium hydride powder.

Laboratory studies only.

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Beneficiation of Titanium

Can we improve current variety and quality of feed to Kroll process to produce a better sponge titanium?Process options include: Becher process,Benilite process, Wah Chang process,Murso process, ERMS process, and titanium slag.

CAMP

Beneficiation of TitaniumGeometallurgy is expanding available resources.Separation and concentration accomplished with comminution, gravity, flotation, magnetic separation, and electrostatic separation.QemScan and MLA are the key tools driving and optimizing these.CAMP will shortly have the only dedicated researchQemScan or MLA in the Western hemisphere.Will be used for minerals, powders, metals, and alloys for rapid chemical phase and size quantifications.

CAMP

Becher Process

Used to upgrade ilmenite to synthetic rutile.Most widely used method.Requires ilmenites at 57-63% TiO2

Process involves heating with coal and iron sulphate in rotary kiln (1,200oC)

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Becher Process

Iron oxides are reduced to elemental iron.Iron is separate by screening and magnetic separation.Rutile is separated by classification using hydrocyclonesFollowed by acid washing, filtration and drying.

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Benilite Process

Involves reduction of iron to ferrous state using fuel oil reductant.Followed by diluted hydrochloric acid leach at elevated temperatures and pressures.Currently used in India and Malaysia.Currently in use in Alabama.

CAMP

Wah Chang Process

Similar to Benelite Process.Used in India.Uses concentrated HCl.

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Murso Process

Ilmenite is oxidized at a temperature of 900-950oC in a fluidized bed reactor.Crystalline structure of ilmenite is changed.Ferric iron is reduced to ferrous and leached using hydrochloric acid.Leached solids are filtered, dried and calcined.

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TSR Process

Partial reduction of iron to FeO state followed by leaching with hydrochloric acid.Similar to Murso Process with ‘improvements’.Used in Canada.

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ERMS Process

Partial reduction of iron to FeO state followed by leaching with hydrochloric acid.Similar to Murso Process.Developed in Australia.

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Titanium Slag Production

Involves smelting of ilmenite in electric furnace under reducing conditions.High purity pig iron is recovered from bottom of the furnace, and slag containing TiO2 is tapped off the furnace.Impurities pass into slag product.

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Titanium Manufacturing and Fabrication

Kroll Process -$3/lb.Plate Manufacturing – $7.5/lbRod Manufacturing – $16.5/lbPossibility of changing current techniques to reduce cost of manufacturing and fabrication of elemental titanium.

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Titanium Manufacturing and Fabrication

Titanium Metal Breakdown Costs

Primary Arc Melt12%

Chlorination9%

Second Melt3%

Rutile4%

Fabrication 47%

Mg Reduction25%

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Fabrication Improvements

High temperature vacuum melting.Very energy intensive (3000-4000oC) and expensive.New developments in electroslag process.Use inert gases and lower temperatures (1700-2000oC)

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Cold hearth electron beam or plasma melting.Technology has been transferred for making automotive materials in treating Kroll titanium sponge.

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Blended Powder Metallurgy– Lower temperatures.– Less purity titanium.– Very little scrap produced.– Alloy production possibility.

Currently being implemented at CAMP

CAMP


Navy Manufacturing Technology– Use titanium machine chips, titanium sponge

powders, and master alloys.– Recycled material required

Lowers overall cost of finished part.

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Manufacturing Improvements

Argon gas atomization– Produces better titanium powder from sponge.– 65% of cost compared to baseline technology.

Many applications possible in powder metallurgy.

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Conclusions

The Department of Defense requires lower cost of elemental titanium and fabrication.For these applications, the corrosion resistance, inherent strength and lower density of titanium metal will provide significantly lower operation costs and more versatile operation capabilities for the Department of Defense.

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ConclusionsThe development of new extraction and non-melt processes offer exciting opportunities to lower production costs of titanium metal and alloys. If new approaches can be commercialized, titanium production will greatly enhance the World.New ideas and long term financial commitments may create advances analogous to the very development of the Kroll process.

CAMP

“The future of our business is based on the supply of sand and brains.”

INTEL Corporation 2005

Our Titanium metal industry was created with the same concept almost 60 years ago.

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Questions

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The TEMPER and Free Form Titanium Fabrication Initiatives

at The Center for Advanced Mineral and Metallurgical

Processing, USA

ByC. G. ANDERSON, P. J. MIRANDA,

and L. G. TWIDWELL

The TEMPER and Free Form Titanium Fabrication Titanium Initiatives at The

Center for Advanced Mineral and Metallurgical Processing, USA

C. G. ANDERSON*, P. J. MIRANDA, and L. G. TWIDWELL The Center for Advanced Mineral and Metallurgical Processing

Montana Tech of the University of Montana, Butte, Montana

Abstract Titanium is a metal of increasing worldwide strategic importance. The Center for Advanced Mineral and Metallurgical Processing (CAMP) at Montana Tech of the University of Montana is currently directing two titanium research initiatives. The first program, Titanium Extraction Mining and Process Engineering Initiative (TEMPER), is focused on producing low cost titanium through the identification and development of new mining, beneficiation and extraction technologies which will significantly reduce the cost of titanium production. This will directly benefit worldwide commercial applications. Secondly, CAMP is evaluating new technologies for fabrication of titanium utilizing the Free Form Titanium Fabrication (FFTF) initiative. These technologies may drastically reduce the cost and time to manufacture titanium components. Because of the high strength to weight ratio of titanium coupled with its superior corrosion characteristics, these programs will be of vital importance to expanding the commercial and strategic applications of titanium. An overview of these two new titanium initiatives will be presented in this paper.

Introduction The driving force behind the original development of titanium production in the 1930’s and 1940's was military aerospace. Today, aerospace applications represent approximately 65% of the titanium market. Because of this reliance on the aerospace industry, titanium demand has been cyclic. For titanium to escape these cycles, the non-aerospace use of titanium must expand. To do this, titanium must economically compete with magnesium, aluminum, and stainless steel. Recently, some progress on improving the Kroll process has been made. Still, the Kroll reduction step remains very similar to the process used by the US Bureau of Mines (USBM) in 1948. Charles River Associates[1] has proposed a 1-10-100 rule to expand the demand for titanium, a $1.00 decrease in the cost of sponge coupled with a 10% reduction in the mill product value-added cost will result in a 100% gain in the volume of the non-aerospace market. For the foreseeable future, the Kroll process will be the method of choice. However, it is apparent there is a need for the development of a new process. The development of such a process will likely require a significant effort of the type made by the USBM in the 1940 and 1950's. As well, fabrication of titanium also is more expensive than steel or aluminum. A typical machined part for an aerospace application may contain

only 10% to 50% of the original titanium. The fabrication cost to produce a component from sponge significantly increases the price of a finished part. For example, the published prices for plate and bar are currently about $7.50 and $16.50 USD per pound, respectively. Precision casting and the use of powder metallurgical techniques can reduce this cost considerably. Because titanium is a reactive metal, it must be melted in an inert atmosphere and the crucible must made of something that will not react with molten titanium. Powder metallurgy is an approach that could reduce the cost of titanium parts considerably. If titanium powder could be made for a price similar to that of sponge, then powder metallurgy could be used to reduce the cost of a titanium part by 50%.

The TEMPER (Titanium Extraction Mining and Process Engineering Initiative) the FFTF (Free Form Titanium Fabrication) programs at the Center for Advanced Mineral and Metallurgical Processing (CAMP) at Montana Tech will address and expedite these future developments. This presentation outlines the details of the program. What are CAMP, TEMPER and FFTF? The Center for Advanced Mineral and Metallurgical Processing (CAMP) is the Center of Excellent for mineral processing, extractive and process metallurgical

engineering on the campus of Montana Tech of The University of Montana located in Butte, Montana, USA. The Center facilitates cooperation between the university system and industry to enhance the economy of the State of Montana by supporting, developing and adding value to the global mineral industry. Economic enhancement is encouraged through added value processing of minerals and metallurgical wastes and developing processes that minimize waste generation. CAMP is a major participant in a newly activated U.S. project called “Titanium Extraction Mining and Process Engineering Research” (TEMPER) and Free Form Titanium Fabrication (FFTF) initiatives. These projects are multiyear efforts supported by The US government to reduce the cost of titanium production and titanium alloy fabrication. These projects have just been initiated at Montana Tech. CAMP’s TEMPER and FFTF objectives for the fiscal years 2004 and 2005 include: Conducting surveys and reviews of • Titanium Bearing Ore Types and Availability • Titanium Ore Physical Beneficiation Processes • Titanium Ore Chemical Beneficiation Processes • Review of the Kroll Process for Producing Titanium Conducting reviews and defining requirements for • Potentially New Emerging Titanium Production Processes • Establishing and Optimizing Titanium Mill Product Fabrication Processes To date the first three objectives have been completed. Presently a detailed review of possibilities for improving the Kroll process is underway. Also, literature reviews, plant visits, use of consultants are presently underway to collect information on new developing processes. TEMPER Project Objectives The US government is presently funding an aggressive and fast paced effect to produce lower cost titanium sponge and titanium high strength alloys. This in analogous to the United States Bureau of Mines programs instituted over a half century ago which developed the commercially dominant Kroll process. The present problem is illustrated in Figure 1, i.e., the cost for available titanium must be drastically decreased from $15-$20/pound to $4-$6/pound. Note in the figure that the proposed approach for reducing the cost of titanium is to increase the supply by augmenting

the presently produced titanium metal with recycled scrap. It may be that insufficient scrap will be available and if that is the case then a new production process may have to be formulated or the existing process (Kroll Process) may have to be improved to increase US capacity while decreasing cost.

Fig.1. The present cost for producing various titanium metal products Production of Titanium The production of titanium in the US is very cyclic and is presently dependent on the requirements of the Aerospace Industry. The cyclic nature is illustrated in Figure 2. Because of the cyclic nature of titanium production the needs of the US government cannot be presently met. Titanium sponge is the raw material for all subsequent steps, i.e., the final alloy materials cost is driven by the cost of the predominant titanium production process (the Kroll Process).

Fig. 2 Cyclic nature of the production of titanium U.S. Suppliers of Titanium Sponge

0

25

50

75

100

125

150

175

1970 1973 1976 1979 1982 1985 1988 1991 1994 1997 2000

US TITANIUM INGOT PRODUCTION (millions of pounds)

7 years 8 years8 years

Aerospace Grade

Product $15-20/lb Plate

Non-aerospaceGrade

Product $11/lb Pl t

TiO2

TiCl4

$0.25/lb

Titanium Processing Steps and Resultant Costs

Vacuum

Vacuum

Sponge & Scrap

Plasma Melt Plasma

Melt

Ti metal

Ti Metal &

Ti Scrap

Plasma Melt

Kroll Sponge

TiCl4

Alternative Non-aerospace Grade Product $4-6/lb Plate

3

The U.S. now has only limited production of titanium sponge. Therefore, approximately 46% of the US current needs for sponge are satisfied by imports. The major suppliers of sponge to the US are Japan (46%), Kazakhstan (34%), and Russia (20%). Russia is presently curtailing all sale of titanium sponge to the US because they want to develop their own industry to supply finished products not raw materials and this is a major problem for the US. Most of the world’s titanium resources are used for the production of titanium dioxide for pigments. Only about five percent of the titanium resources are used to produce sponge titanium. The US is a rather large titanium dioxide producer from its own resources and is actually a net exporter of the product. The global sponge production capacity is presented in Table 1. Note that only 100,000 metric tons per year of sponge capacity presently exists (this is down 17% from 1990). It is also noteworthy that US domestic consumption of titanium sponge increased an estimated 33% in 2004 compared to 2003[2] and that an additional capacity of 4000 Mtpy was announced in 2005 to become effective by 2007[3].

Table 1. World Sponge Titanium Capacity (2004)

Research Directions

The possible solutions to the limited supply and high cost of titanium are to improve the existing titanium production process and/or demonstrate the commercial reliability of a new process and to improve and innovate the manufacturing and fabricating capabilities for the production of the desired alloys. The Kroll Process All of the US sponge titanium is produced by the Kroll Process by one company. This process was developed in the 1940’s and is still widely used. Briefly, the process is

a multistage process that converts rutile or ilmenite to titanium tetrachloride by carbon/chlorine gas roasting, purification of the titanium tetrachloride by fractional distillation, reduction of the titanium tetrachloride using magnesium or sodium as the reductant at approximately 750oC, subsequent recovery of sponge titanium, and purification of the product by leaching, followed by electron beam melting or electric arc/vacuum melting. One of the objectives of the present initial evaluation is to define potential ways to improve the Kroll Process. To achieve low cost titanium for applications, it is critical that a U.S. Kroll alternative titanium production capability be established. To achieve massive increases in the use of titanium, it is also essential that new titanium capability be established to meet the increase demand reliably. The current capability to produce titanium sponge to meet even a doubling of the current volumes does not exist. Therefore, new production methods must be installed. Other Processes for Producing Titanium Another task that CAMP is undertaking for the TEMPER initiative is to identify, characterize, innovate, and recommend the development of new titanium producing processes. This task is just in the beginning stages. However, a number of potential processes have been identified by EKH Industries[4]. A preliminary list of potential processes has been assembled. These processes will be considered in our evaluations and recommendations made concerning possible future demonstration test work: • FCC/Cambridge/TIMET-electrolytic reduction of partially sintered TiO2 in a molten salt bath at 950oC (status: laboratory studies and pilot scale tested). This is a highly touted potentially less expensive process than the Kroll process and produces a product that contains much less oxygen (which is highly desirable). However, the process requires that the starting material be relatively high purity TiO2. For this process to be successful it requires not only that the electrolysis be successful but also that there be a cheap source of TiO2, which may be a problem. TIMET has been selected by the US Defense Advanced Research Projects Agency (DARPA) to lead a program for developing the FCC/Cambridge Process. Recent funding of $12.3 million dollars has been announced. A subcontract has also just been announced (February 2004) for Altair Nanotechnologies to investigate the production of TiO2 pellets using their expertise in nanotechnology. Altair will be investigating the formation of palletized

County Production Capacity, % (based on 100,000 Mtpy)

Japan 31

Russia 26

Kazakhstan 22

United States 9

China 7

USGS, 2005[2]

anodic materials that have extremely high surface areas because of their nanotechnology advances to produce high porosity materials in large quantities at minimal cost. • Armstrong/International Ti Powder-liquid sodium reduction of TiCl4 vapor (pilot study completed). The Armstrong Process uses a jet of TiCl4 (and alloy vaporous chlorides if an alloy is desired) which is injected into a flowing stream of sodium (reductant) (has been pilot scale tested to produce high purity titanium and titanium alloys). The product from this process is titanium powder which is a desirable product for use in subsequent powder metallurgical processing. The pilot plant operation was successful and the process is according to its developers “close to commercialization”. Studies for controlling particle size within the range 50-300 micrometers (required for conventional powder metallurgy) and morphology for product applications must still be completed. • MER Corporation-anode reduction of TiO2, transport through a mixed halide electrolyte, deposition of Ti on cathode (status: unknown state of development). MER has also been awarded a DARPA contract to continue their development studies. Pilot studies need to be performed. Process economics and product acceptability must be demonstrated. • SRI International-fluidized bed reduction of TiCl4 onto metallic substrates (status: laboratory studies to date). SRI has been awarded a DARPA contract to continue process development. Pilot demonstrations must be performed and product acceptability and economics must be demonstrated. • BHP Billiton-electrolytic reduction of TiO2 in a CaCl2 based bath (status: laboratory studies completed; small pilot plant demonstration is presently planned). Plans are to achieve commercialization by 2009. Although the BHP process is electrolytic it is claimed that the process is substantially different than the Cambridge Process but details of the process are not presently available • Idaho Titanium Technologies-hydrogen reduction of TiCl4 in a plasma reactor (status: laboratory studies; pilot test work completed at 40 lb/hr). Process quenches a hydrogen/titanium tetrachloride plasma so that back reaction of the powdered titanium hydride with chlorine does not occur and very low chloride and oxygen are present in the product. Cost is estimated to be slightly

less than sponge produced by the Kroll Process but with much lower concentrations of oxygen and chlorine. However, the product is titanium hydride and must be further processed to remove the hydrogen. Pilot demonstrations must be performed and product acceptability and economics must be demonstrated . • OS Process-Kyoto University-calciothermic reduction of TiO2 in a calcium chloride electrolyte (status: laboratory scale studies have progressed to larger scale test work with the Japanese aluminum industry, present status is unknown). Oxygen contents of <100 ppm are reported achievable. The product is granules of lightly sintered titanium metal. Separation of the titanium product from the bath constituents must still be solved. • MIRChem and University of Bremen-iodine reduction of TiO2 in shaking reactor (status: laboratory scale studies only). Extremely long dwell time is required to complete the reaction forming titanium tetraiodide. The titanium tetraiodide must subsequently be disassociated to titanium and iodine gas. Pilot demonstrations must be performed and product acceptability and economics must be demonstrated. • CSIR-South Africa-hydrogen reduction of TiO2 (status: laboratory scale studies have led to patent applications). Process is in its very earliest stages of development. • Quebec Rio Tinto (status: current status is unknown). Quebec Iron and Titanium is a recognized world producer of titania bearing slags. They have filed patent applications for an electrolytic conversion process using titania slags as the titanium source. The process involves pouring molten slag and molten electrolyte into an Electric Arc Furnace. The electrolysis is then carried out in two stages where first impurities are reduced to the metallic state and collect in the bottom of the furnace and is removed; then the temperature is raised and titanium is electrolyzed and the metal collects in the furnace bottom. • EMR/MSE Process University of Tokyo. Electrolytic reduction of TiO2 powder (status: laboratory scale studies, unknown state of development, mechanism for the process has not been identified). • Preform Reduction-University Tokyo-reduction of TiO2 by calcium vapors (status: laboratory scale studies, unknown state of development). Use of elemental

5

calcium likely to result in a very expensive process. • Idaho Research Foundation-mechanochemical reduction of TiCl4 by magnesium, calcium or their hydrides in a ball mill (status: laboratory studies only). Product is titanium hydride power. Techniques for Beneficiating and Producing Titanium Dioxide A portion of our evaluation process will be to consider whether present beneficiation processes utilized for the production of titanium dioxide can be better utilized to produce a relatively pure titanium sponge or powder product. Examples of these beneficiation processes include the Becher process, the Benilite process, the Wah Chang process, the Murso process, the ERMS process, and the titanium slag process. Due to space constraints, the details of these will not be elucidated in this paper. However, through enhanced beneficiation technologies, it may be possible to use non traditional titanium ores or lower quality intermediary products for metal production at a significantly lower cost. For example, beneficiation of vast untapped titanium ore resources such as perovskite, CaTiO3 , is being evaluated by CAMP in this research program in collaboration with some Ukranian technical organizations. Manufacturing and Fabrication It may very well be that only limited improvements can be made in lowering the cost of titanium production, even with the introduction of completely new innovative technologies. The cost of producing sponge titanium presently is about $3/lb using the Kroll process, whereas the cost of manufactured plate and rods are approximately $7.50/lb and $16.50/lb respectively[4]. Even though a large percentage of the cost of producing titanium products is for sponge production a relatively large percentage is for manufacturing and fabrication (Figure 3). Therefore, the present project will evaluate and may propose major changes in manufacturing and fabrication technologies and procedures rather than emphasizing changes in sponge production technologies.

Fig 3. Relative costs for production of titanium parts. Examples of potential areas of manufacturing and fabrication improvements are presented[4] below: • Improvements in sponge purification-present day purification use high temperature high vacuum processes to volatilize impurities during remelting of titanium sponge. These processes are very energy intensive (3000-4000oC) and expensive. Recent developments in electroslag processing and induction melting technologies may be applicable to titanium purification. The processes can be conducted in an inert gas rather than in a high vacuum and at much lower temperatures (1700-2200oC). • Application of cold hearth electron beam or plasma melting has been widely adopted and utilized in producing lower cost titanium. This technology has been transferred from making automotive titanium materials to use in treating Kroll sponge titanium. • Blended powder metallurgy applications can produce some parts at relatively low temperatures using less pure titanium powders. The production of parts using powder metallurgy saves material because near final shapes can be formed prior to pressing the final product and very little scrap titanium is produced. An example of this being implemented and researched at CAMP is patented 3DP free form fabrication. Also some of the new titanium production processes listed above produce a powder product rather than a sponge product which may find applications in powder metallurgy. Development of powder metallurgy armor alloy fabrication may be an important direction for this project. • A Navy Manufacturing Technology program is focusing on using a mixture of products and advances in casting to produce their desired end product. They use titanium machining chips, titanium sponge powders and master alloys to provide the final desired casting composition, thereby using recycled materials and less sponge to reduce the need for sponge and to reduce the final part cost. • Use of Argon Gas Atomization (AGA) is a way to

Titanium Metal Breakdown Costs

Primary Arc Melt12%

Chlorination9%

Second Melt3%

Rutile4%

Fabrication 47%

Mg Reduction25%

produce titanium powder from titanium sponge. This process has been proposed to save approximately 65% on the price of normally produced titanium powder. Many applications (using powder metallurgy) do not require high purity electron beam produced titanium.

Summary The Department of Defense now has a large and extensive program to not only develop low cost titanium metals, but also lower cost fabrication processes to deliver lower component procurement cost for non-aerospace military applications. For these applications, the corrosion resistance, inherent strength and lower density of titanium metal will provide significantly lower operation costs and more versatile operation capabilities for the Department of Defense. Procurement costs have been the major obstacle for implementation in critical applications. The development of new extraction and non-melt processes offer exciting opportunities to lower production costs of titanium metal and alloys. If these new approaches are commercialized in a fashion analogous to the development of the Kroll process, once again, the establishment of a U.S. production base for these processes will greatly enhance the nation. Finally, the TEMPER and FFTF projects have just been initiated at CAMP. Accomplishment of the initial reviews and evaluations should result in the delineation of pathways to achieve expanded capabilities for the production of titanium and for improvements and innovations in the fabrication and manufacture of titanium products. As with the USBM development program resulting in the Kroll process a half century ago, expect to see major contributions and publications resulting from the present study.

References [1] Personal communication, Charles River Associates,

[2] USGS Mineral Commodities Summaries, Titanium and Titanium

Dioxide, Minerals, http://usgs.gov/minerals, July 26, 2005.

[3] USGS Mineral Industry Surveys, Titanium in the First Quarter

2005 http://minerals.usgs.gov/minerals/pubs/commodity/mis.html,

July 26 2005.

[4] EKH Technologies, Summary of Emerging Titanium Cost

Reduction Technologies, Study for US DOE, Contract

4000023694, January 2004, 59p.

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