Skip Nav Destination
Close Modal
By
Luther M. Gammon, Robert D. Briggs, John M. Packard, Kurt W. Batson, Rodney Boyer ...
Search Results for
Kroll process
Update search
Filter
- Title
- Authors
- Author Affiliations
- Full Text
- Abstract
- Keywords
- DOI
- ISBN
- EISBN
- Issue
- ISSN
- EISSN
- Volume
- References
Filter
- Title
- Authors
- Author Affiliations
- Full Text
- Abstract
- Keywords
- DOI
- ISBN
- EISBN
- Issue
- ISSN
- EISSN
- Volume
- References
Filter
- Title
- Authors
- Author Affiliations
- Full Text
- Abstract
- Keywords
- DOI
- ISBN
- EISBN
- Issue
- ISSN
- EISSN
- Volume
- References
Filter
- Title
- Authors
- Author Affiliations
- Full Text
- Abstract
- Keywords
- DOI
- ISBN
- EISBN
- Issue
- ISSN
- EISSN
- Volume
- References
Filter
- Title
- Authors
- Author Affiliations
- Full Text
- Abstract
- Keywords
- DOI
- ISBN
- EISBN
- Issue
- ISSN
- EISSN
- Volume
- References
Filter
- Title
- Authors
- Author Affiliations
- Full Text
- Abstract
- Keywords
- DOI
- ISBN
- EISBN
- Issue
- ISSN
- EISSN
- Volume
- References
NARROW
Format
Topics
Book Series
Date
Availability
1-20 of 57 Search Results for
Kroll process
Follow your search
Access your saved searches in your account
Would you like to receive an alert when new items match your search?
1
Sort by
Image
Published: 30 September 2015
Fig. 1 The modified Kroll process per ADMA Products, Inc. involves the use of hydrogen to break down the titanium sponge produced in the present-day titanium reactors. It eliminates the comminution process (boring, shearing, crushing), considerably reduces the vacuum distillation time
More
Image
Published: 30 September 2015
Fig. 2 Titanium hydride powder production (modified Kroll process). The hydrogenation reactions within the titanium extraction process convert the sponge into titanium powder (or sponge fines) in lieu of the currently produced titanium sponge, per Ref 3 . The powdered TiH 2 shown
More
Image
Published: 30 September 2015
Fig. 3 Powder raw materials. (a) Titanium sponge as extracted by the Kroll process. (b) Titanium sponge after crushing and cutting. (c) Titanium sponge fines (–100 mesh) of unalloyed titanium, obtained as byproduct of the Kroll magnesium process in (a), too small to be used in the melting
More
Book: Powder Metallurgy
Series: ASM Handbook
Volume: 7
Publisher: ASM International
Published: 30 September 2015
DOI: 10.31399/asm.hb.v07.a0006078
EISBN: 978-1-62708-175-7
... Abstract This article provides a summary of the conventional technologies used for titanium powder production. It focuses on the various processes for titanium powder production, namely, Hunter, Kroll, Armstrong, MER, TIRO, FFC-Cambridge, Chinuka, and CSIR processes. Employment of titanium...
Abstract
This article provides a summary of the conventional technologies used for titanium powder production. It focuses on the various processes for titanium powder production, namely, Hunter, Kroll, Armstrong, MER, TIRO, FFC-Cambridge, Chinuka, and CSIR processes. Employment of titanium powder significantly improves the synthesis of titanium and its alloys.
Image
Published: 30 September 2015
Fig. 2 Time-temperature profiles comparing (a) hydriding and vacuum distillation using conventional Kroll's process and (b) ADMA Products' TiH 2 process
More
Series: ASM Handbook
Volume: 2
Publisher: ASM International
Published: 01 January 1990
DOI: 10.31399/asm.hb.v02.a0001080
EISBN: 978-1-62708-162-7
... (50 million lb/yr). The catalyst for this remarkable growth was the development by Dr. Wilhelm J. Kroll of a relatively safe, economical method to produce titanium metal in the late 1930s. Kroll's process involved reduction of titanium tetrachloride (TiCl 4 ), first with sodium and calcium...
Abstract
Titanium has been recognized as an element with good mechanical and physical properties, alloying characteristics, and corrosion resistance. Providing an outline of general characteristics and types of titanium alloys, this article discusses the contemporary technology of titanium along with its market developments. It also discusses the application of titanium and titanium alloys in corrosive environments and in aerospace and automotive industries. The article describes the developments in titanium processing and materials technologies, which include the development of sponge production and melting processes, oxide dispersion-strengthened alloys by powder metallurgy techniques, titanium-base intermetallic compounds, and titanium-matrix composites.
Book Chapter
Series: ASM Desk Editions
Publisher: ASM International
Published: 01 December 1998
DOI: 10.31399/asm.hb.mhde2.a0003149
EISBN: 978-1-62708-199-3
... by using the Kroll process developed at the U.S. Bureau of Mines by W.J. Kroll in 1947. Extraction is accomplished by mixing the zircon with carbon in the form of coke; the mixture is then chlorinated to produce a high-temperature gas stream containing silicon tetrachloride in addition to zirconium...
Abstract
This article discusses the general characteristics, primary and secondary fabrication methods, product forms, and corrosion resistance of zirconium and hafnium. It describes the physical metallurgy of zirconium and its alloys, providing details on allotropic transformation and anisotropy that profoundly influences the engineering properties of zirconium and its alloys. Tables listing the values for chemical composition and tensile properties for nuclear and nonnuclear grades of zirconium are also provided.
Book Chapter
Series: ASM Handbook
Volume: 9
Publisher: ASM International
Published: 01 December 2004
DOI: 10.31399/asm.hb.v09.a0003779
EISBN: 978-1-62708-177-1
... documented for intermediate and final polishing that may fit different operations. The list below discusses of a few of the procedures. An example of abusive polishing is shown in Fig. 5 after etching. Excessive etching cannot correct poor specimen preparation. Fig. 5 Etched with Kroll's reagent...
Abstract
This article describes the fundamentals of titanium metallographic sample preparation. Representative micrographs are presented for each class of titanium alloys, including unalloyed titanium, alpha alloys, alpha-beta alloys, and beta titanium alloys. The article provides information on the macroexamination and microexamination for these alloys. It concludes with a discussion on the several metallographic techniques developed for specific purposes, such as recrystallization studies and microstructure/fracture topography correlations.
Image
Published: 01 December 2004
Fig. 31 High-purity (iodide-process) unalloyed titanium sheet, cold rolled, and annealed 1 h at 700 °C (1290 °F). Equiaxed, recrystallized grains of alpha. Etchant: Kroll's reagent (ASTM 192). 250×
More
Series: ASM Handbook
Volume: 2
Publisher: ASM International
Published: 01 January 1990
DOI: 10.31399/asm.hb.v02.a0001084
EISBN: 978-1-62708-162-7
... purified by sublimation; it is then reduced to the metal with magnesium by the Kroll process. The resulting porous metal is called sponge metal. Distillation Separation Process In the distillation separation process ( Ref 2 ), the crude product obtained after chlorinating the zircon sand is purified...
Abstract
Zirconium, hafnium, and titanium are produced from ore that generally is found in a heavy beach sand containing zircon, rutile, and ilmenite. This article discusses the processing methods of these metals, namely, liquid-liquid separation process, distillation separation process, refining, and melting. It also discusses the primary and secondary fabrication of zirconium and hafnium and its alloys. The article talks about the metallurgy of zirconium and its alloys with emphasis on allotropic transformation, cold work and recrystallization, anisotropy and preferred orientation, and the role of oxygen. It concludes by providing useful information on the applications of reactor and industrial grades of zirconium alloys.
Book Chapter
Series: ASM Handbook
Volume: 9
Publisher: ASM International
Published: 01 December 2004
DOI: 10.31399/asm.hb.v09.a0003785
EISBN: 978-1-62708-177-1
... 13 mm (0.5 in.) Ti-6Al-2Nb-1Ta-1Mo alloy plate, autogenous single-pass gas tungsten arc weld. Heat input: 2.0 MJ/m. Longitudinal section showing curvature of the prior-β grains, which follow the maximum thermal gradient in the weld pool. Etchant: one-to-one solution, Kroll's reagent and distilled...
Abstract
This article provides a review of metallographic procedures and techniques for analyzing the microstructure of fusion welded joints. It discusses sample preparation, the use of backing plates, and common sectioning methods. It identifies the various types of defects that can occur in arc welded metals, organizing them according to the sectioning method by which they are observed. It describes the relationship between weld bead morphology and sectioning direction and its effect on measurement error. The article examines micrographs from stainless steel, aluminum, and titanium alloy joints, highlighting important details such as solidification and solid-state transformation structures and what they reveal about the welding process. Besides arc welding, it also discusses laser and electron beam welding methods, resistance and spot welding, and the welding of dissimilar metals.
Book: Powder Metallurgy
Series: ASM Handbook
Volume: 7
Publisher: ASM International
Published: 30 September 2015
DOI: 10.31399/asm.hb.v07.a0006095
EISBN: 978-1-62708-175-7
... charged into the hot reactor, turning the sponge product into titanium hydride—TiH 2 —(BE) powder, and thus modifying the Kroll process for titanium extraction from its ore as shown in Fig. 1 and 2 ( Ref 3 ). Conversion of the sponge products shown in Fig. 3(a) to (c) into essentially 100% TiH 2...
Abstract
This article focuses on mechanical testing characterization of blended elemental powder metallurgy (PM) titanium alloys and prealloyed PM titanium alloys. It examines the tensile properties, fracture toughness, stress-corrosion threshold resistance, fatigue strength, crack propagation properties, and processing-microstructure-property relationships of these alloys. The article also reviews five considerations for powder process selection.
Book: Powder Metallurgy
Series: ASM Handbook
Volume: 7
Publisher: ASM International
Published: 30 September 2015
DOI: 10.31399/asm.hb.v07.a0006087
EISBN: 978-1-62708-175-7
.... In these cases, the gaseous metal chlorides are reduced with liquid sodium or magnesium (Kroll process). The reaction product is leached with dilute hydrogen chloride to remove sodium chloride and/or magnesium chloride. The result is a metallic sponge material that is subsequently pulverized. Hydride...
Abstract
This article provides a discussion on the process descriptions, processing conditions, and processing variables of the most common chemical methods for metal powder production. These methods include oxide reduction, precipitation from solution, and thermal decomposition. Methods such as precipitation from salt solution and gas, chemical embrittlement, hydride decomposition, and thermite reactions are also discussed. The article also discusses the methods used to produce powders electrolytically and the types of metal powders produced. The physical and chemical characteristics of these powders are also reviewed.
Series: ASM Handbook
Volume: 2
Publisher: ASM International
Published: 01 January 1990
DOI: 10.31399/asm.hb.v02.a0001092
EISBN: 978-1-62708-162-7
... for bismuth in commercial lead. The two most important methods for removing bismuth from lead are the Betterton-Kroll process and the Betts process. The Betterton-Kroll process is based on the formation of high-melting compounds such as Ca 2 Bi 2 and Mg 3 Bi 2 that separate from the molten lead bullion bath...
Abstract
This article focuses on the use of indium and bismuth in low-melting-temperature solders and fusible alloys. It describes how the two elements typically occur in nature and how they are recovered and processed for commercial use. It also provides information on designations, classification, composition, properties (including temperatures ranges), and some of the other ways in which indium and bismuth alloys are used.
Book: Powder Metallurgy
Series: ASM Handbook
Volume: 7
Publisher: ASM International
Published: 30 September 2015
DOI: 10.31399/asm.hb.v07.a0006045
EISBN: 978-1-62708-175-7
... Process for Producing Low Cost Titanium and Titanium Alloy Components , Titanium 2008: 24th Annual ITA Conference & Exhibition , Sept 21–24, 2008 ( Las Vegas, NV ), International Titanium Association 16. Duz V. et al. , Innovative Non-Kroll Process for Hydrogenated Titanium Powder...
Abstract
Consolidation of titanium powders at room temperature may be performed by low-cost conventional powder metallurgy processes. This article provides information on various consolidation methods, namely, die pressing, direct powder rolling, and cold isostatic pressing. It also describes the sintering of blended elemental powders, high-strength titanium alloys, and porous material as well as the sintering of titanium powders by microwave heating.
Book: Corrosion: Materials
Series: ASM Handbook
Volume: 13B
Publisher: ASM International
Published: 01 January 2005
DOI: 10.31399/asm.hb.v13b.a0003826
EISBN: 978-1-62708-183-2
... uses an extractive distillation process, while in the United States a liquid-liquid extraction is the preferred method. Two primary operational methods of metal production are also possible. The Kroll process is the primary reduction process used in the United States, while in Europe an electrowinning...
Abstract
This article describes the processes involved in the production of hafnium and its alloys. It discusses the physical, mechanical and chemical properties of hafnium. The aqueous corrosion testing of hafnium and its alloys is detailed. The article reviews the corrosion resistance of hafnium in specific media, namely, water, steam, hydrochloric acid, nitric acid, sulfuric acid, alkalis, organics, molten metals, and gases. Forms of corrosion, namely, galvanic corrosion, crevice corrosion, and pitting corrosion are included. The article explains the corrosion of hafnium alloys such as hafnium-zirconium alloys and hafnium-tantalum alloys. It also deals with the applications of hafnium and its alloys in the nuclear and chemical industries.
Series: ASM Handbook
Volume: 11
Publisher: ASM International
Published: 15 January 2021
DOI: 10.31399/asm.hb.v11.a0006760
EISBN: 978-1-62708-295-2
.... They are similar to folds and can act as stress raisers during forming processes. Seams have blunt tips. The two sides of a seam do not necessarily match ( Fig. 36 ). Fig. 36 (a) Surface of Ti-6Al-4V bar with seams. (b) Section through seams showing oxide and blunt tips. Kroll’s etch Cracks Cracks...
Abstract
Visual examination, using the unaided eye or a low-power optical magnifier, is typically one of the first steps in a failure investigation. This article presents the guidelines for selecting samples for scanning electron microscope examination and optical metallography and for cleaning fracture surfaces. It discusses damage characterization of metals, covering various factors that influence the damage, namely stress, aggressive environment, temperature, and discontinuities.
Book: Powder Metallurgy
Series: ASM Handbook
Volume: 7
Publisher: ASM International
Published: 30 September 2015
DOI: 10.31399/asm.hb.v07.a0006136
EISBN: 978-1-62708-175-7
... – 61 17. Barnes J. E. , Williams J. , Blue C.A. , and Peter B. , Titanium Powder Metallurgy–What's After the Kroll Process? , Titanium-2012 ITA Conference , Oct 2012 , Atlanta, GA ...
Abstract
Direct powder rolling (DPR) is a process by which a suitable powder or mixture of powders is compacted under the opposing forces of a pair of rolling mill rolls to form a continuous green strip that is further densified and strengthened by sintering and rerolling. This article discusses the basic principle, process considerations, and advantages of DRP, and describes the application of this process in the manufacture of powder titanium and titanium alloy components. It further illustrates the complexity of the process and describes the benefits of using DRP in terms of economics and product quality.
Series: ASM Handbook
Volume: 1A
Publisher: ASM International
Published: 31 August 2017
DOI: 10.31399/asm.hb.v01a.a0006351
EISBN: 978-1-62708-179-5
... in the as-polished and etched conditions. Note that the as-polished image shows a variation in the contrast of the eutectic carbide patterns, which suggests either a crystallographic difference and/or chemical segregation variations. Etching with Kroll’s reagent followed by Vilella’s reagent also showed image...
Abstract
This article describes two contemporary approaches for preparing cast iron specimens with a wide range of phases and constituents as well as different graphite morphologies. It introduces concepts and preparation materials that enable metallographers to shorten the process while producing better, more consistent results. Recommended procedures to prepare cast irons and examples of high-alloy cast iron microstructures revealed using a variety of etchants are presented. Several etchants are used to reveal the matrix microstructure, depending on the alloy content. The article discusses the use of black and white etchants and lists the compositions of abrasion-resistant cast irons according to ASTM A532/A532M in a table.
Book: Casting
Series: ASM Handbook
Volume: 15
Publisher: ASM International
Published: 01 December 2008
DOI: 10.31399/asm.hb.v15.a0005203
EISBN: 978-1-62708-187-0
... of Titanium Castings,” Report 5265, U.S. Bureau of Mines , Aug 1956 , p 42 2. Kroll W.J. , Anderson C.T. , and Gilbert H.L. , A New Graphite Resistor Vacuum Furnace and Its Application in Melting Zirconium , Trans. AIME , Vol 175 , 1948 , p 766 – 773 3. Harding R.A...
1