DOCSLIB.ORG

Copper-Platinum Alloys

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Copper-Platinum Alloys Copper-Platinum Alloys THE EQUIATOMIC Cu-Pt SUPERLATTICE R. S. Irani and R. W. Cahn Materials Science Laboratory, University of Sussex, Brighton, England We have been trying to elucidate the phase reactions. Moreover, the structural mechanisms of ordering of the lattice structure change involved (a rhombohedral lattice in various copper alloy systems, among which replacing a cubic one) means that substantial the copper-platinum system is especially internal stresses are created which sub- interesting because of its unique features. sequently strengthen the material during rhe The random f.c.c. solid solution in the course of transformation, as shown in Fig. 2. equiatomic copper-platinum system shown in Such hardening behaviour, coupled with the Fig. Ia is replaced below the critical temper- corrosion and oxidation resistance of the ature of 812°C by a long-range ordered alloy, can be usefully employed when the rhombohedral lattice. The latter superlattice configuration consists of alternate layers of pure copper and pure platinum atoms arranged parallel to the (111) planes, there being the same number of nearest neighbours in both the ordered and disordered states, as shown in Fig. Ib. CuPt is the only known superlattice with this structure but in fact surprisingly little work has been performed on the equiatomic alloy. The fact that there is no change in the number of nearest neighbours upon ordering has meant that most existing theories fail to account for the ordering in CuPt. However, Clapp and Moss (I) have attempted a formu- lation in terms of first and second nearest neighbours, the approach being referred to as the central pair-wise (CPW) model. The analysis predicts the long-range order be- haviour from short-range order data, obtained by Walker (2) from diffuse X-ray scattering experiments on powdered samples, but there is no mention of why CuPt orders at all. The theory could be more rigorously tested using diffuse X-ray scattering from single-crystal samples of CuPt. Our recent experimental study (3) has shown that Curt conforms to the earlier established thermodynamic criteria (4) that order-disorder transformations are first-order Platinum Metals Rev., 1972, 16, (2), 48-49 48 alloy has been annealed for intermediate Fig. 3 Thermally polished sample of equiatomic times below the critical temperature (81zT). copper-platinum ulloy observed under polarised A thermal polishing technique (5) for pro- light after annealing for 8% at 550'C, showing ordered domains growing from surface imperfec- ducing strain-free surfaces without recourse tions, e.p. grain boundaries and pores to electrolytic polishing, which is impractic- able, has meant that it is now possible to References perform polarised light metallography on bulk I P. C. Clapp and S. C. Moss, Phys. Rev., 1966, samples of CuPt (see Fig. 3) and thus interpret 142,418; 1968, 171,754; 1968, I7Ii 764 2 C. Walker,J. Appl. Phys., 1952, 23, 1x8 the mechanical characteristics in terms of the 3 R. S. Irani and R. W. Cahn, Nature, 1970, ordered morphologies. 226, I045 Further work is in progress and a forth- 4 F. N. Rhines and J. B. Newkirk, Trans. A.S.M., 19.53, 45, 1029 coming publication will provide full details of 5 R. S. Irani and R. W. Cahn, Metallography, our studies. 1971, 4, 91 Palladium-Silicon Alloys The high affinities of both palladium and tectically at 822'C. The first eutectic is platinum for silicon are well known, for dis- formed between pure palladium and PdjSi astrous consequences result when these metals and melts at 825OC. A second eutectic melting are heated under reducing conditions in at 798°C then forms between Pd,Si and Pd,Si. contact with siliceous materials. Although The diagram advanced by Roschel and low melting point phases are formed, the Raub, although considerably more compli- alloying processes which result in this eutectic cated than that previously accepted, is soundly formation have been incompletely under- based on the thermal analysis and metallo- stood and since 1957 (I) it has been known graphic evidence, both of which fix the that the palladium-silicon diagram originally eutectic compositions very precisely. Al- published in Hansen was inaccurate. Rao though the structures of Pd,Si and Pd,Si have and Winterhagen confirmed the existence of not been completely elucidated, their the compound Pd,Si but concluded incor- diffraction lines are tabulated in considerable rectly that it reacted directly with pure pal- detail and the only remaining uncertainty in ladium to form a eutectic melting at 760°C. this system is the extent of the primary solid Dr E. Roschel and Dr C. J. Raub of the solution of silicon in palladium As previously Forschungsinstitut fur Edelmetalle at showr? (3) this interstitially dissolved silicon Schwabisch Gmund (2) have now re-examined causes discontinuous yielding effects. the system, using silicon of semiconductor A. S. D. quality, and have revealed a fairly complex References situation. As silicon is taken up by palladium, I N. K. Rao and H. Winterhagen, Trans. the compounds Pd,Si and PdaSi are suc- Indian Inst. Metals, 1956-57, 10, 139-148 E. Roschel and C. J. Raub, Z. MetaZlkunde, cessively formed. Pd,Si and Pd$i melt 2 1971,62, (11), 840-842 congruently at 835" and 1070OC and the 3 R. G. Hollister and A. S. Darling, Platinum intermediate compound Pd,Si forms peri- Metals Rev., 1967~IT, (3), 94-99 Platinum Metals Rev., 1972, 16, (2) 49 .
Load more

Recommended publications
  • Treatise on Combined Metalworking Techniques: Forged Elements and Chased Raised Shapes Bonnie Gallagher
    Rochester Institute of Technology RIT Scholar Works Theses Thesis/Dissertation Collections 1972 Treatise on combined metalworking techniques: forged elements and chased raised shapes Bonnie Gallagher Follow this and additional works at: http://scholarworks.rit.edu/theses Recommended Citation Gallagher, Bonnie, "Treatise on combined metalworking techniques: forged elements and chased raised shapes" (1972). Thesis. Rochester Institute of Technology. Accessed from This Thesis is brought to you for free and open access by the Thesis/Dissertation Collections at RIT Scholar Works. It has been accepted for inclusion in Theses by an authorized administrator of RIT Scholar Works. For more information, please contact [email protected]. TREATISE ON COMBINED METALWORKING TECHNIQUES i FORGED ELEMENTS AND CHASED RAISED SHAPES TREATISE ON. COMBINED METALWORKING TECHNIQUES t FORGED ELEMENTS AND CHASED RAISED SHAPES BONNIE JEANNE GALLAGHER CANDIDATE FOR THE MASTER OF FINE ARTS IN THE COLLEGE OF FINE AND APPLIED ARTS OF THE ROCHESTER INSTITUTE OF TECHNOLOGY AUGUST ( 1972 ADVISOR: HANS CHRISTENSEN t " ^ <bV DEDICATION FORM MUST GIVE FORTH THE SPIRIT FORM IS THE MANNER IN WHICH THE SPIRIT IS EXPRESSED ELIEL SAARINAN IN MEMORY OF MY FATHER, WHO LONGED FOR HIS CHILDREN TO HAVE THE OPPORTUNITY TO HAVE THE EDUCATION HE NEVER HAD THE FORTUNE TO OBTAIN. vi PREFACE Although the processes of raising, forging, and chasing of metal have been covered in most technical books, to date there is no major source which deals with the functional and aesthetic requirements
    [Show full text]
  • Repoussé Work for Amateurs
    rf Bi oN? ^ ^ iTION av op OCT i 3 f943 2 MAY 8 1933 DEC 3 1938 MAY 6 id i 28 dec j o m? Digitized by the Internet Archive in 2011 with funding from Boston Public Library http://www.archive.org/details/repoussworkforamOOhasl GROUP OF LEAVES. Repousse Work for Amateurs. : REPOUSSE WORK FOR AMATEURS: BEING THE ART OF ORNAMENTING THIN METAL WITH RAISED FIGURES. tfjLd*- 6 By L. L. HASLOPE. ILLUSTRATED. LONDON L. UPCOTT GILL, 170, STRAND, W.C, 1887. PRINTED BY A. BRADLEY, 170, STRAND, LONDON. 3W PREFACE. " JjJjtfN these days, when of making books there is no end," ^*^ and every description of work, whether professional or amateur, has a literature of its own, it is strange that scarcely anything should have been written on the fascinating arts of Chasing and Repousse Work. It is true that a few articles have appeared in various periodicals on the subject, but with scarcely an exception they treated only of Working on Wood, and the directions given were generally crude and imperfect. This is the more surprising when we consider how fashionable Repousse Work has become of late years, both here and in America; indeed, in the latter country, "Do you pound brass ? " is said to be a very common question. I have written the following pages in the hope that they might, in some measure, supply a want, and prove of service to my brother amateurs. It has been hinted to me that some of my chapters are rather "advanced;" in other words, that I have gone farther than amateurs are likely to follow me.
    [Show full text]
  • Testing Gold Platinum Silver.Qxp
    PROCEDURES FOR TESTING GOLD, PLATINUM AND SILVER To test for the karat value of gold, platinum and silver, you will need the following materials and tools: • Black acid testing stone that is washed thoroughly with water prior to each test. • Acids. • Gold testing needles with gold tips - used for comparison with test pieces. Testing for 10K, 12K, 14K Scratch the gold piece to be tested on the stone. Next to this position, scratch the appropriate needle (10, 12 or 14K). Place a drop of the appropriate acid on the stone where the gold was rubbed off. If the gold is the same karat or higher, the color of the scratch mark for the gold piece will appear the same as the mark from the needle. If that gold piece is a lower karat, the scratched deposit will become fainter and eventually disappear. Testing for 18K Scratch the test piece on the stone and apply 18K acid. Any gold that is less than 18K will disappear in less than 30 seconds. Gold that remains on the stone is 18K or higher. Testing for 20K and 24K Scratch the gold piece on the stone. Next, scratch any item of know karat (coin or needle) on the stone. Apply one drop of acid to area. The material that starts to disappear has the lower karat. Testing for Platinum Scratch the test item on the stone and apply one drop of acid to the application on the stone. If the material is platinum, it should keep its white, bright color. White Gold The same procedure for platinum can be used for 18K white gold.
    [Show full text]
  • The Platinum/Palladium Process
    9 The Platinum/Palladium Process OVERVIEW AND EXPECTATIONS In the majority of the classes and workshops that I’ve taught over the years, “the platinum/palladium process” is the answer that surfaces first when I ask the question, “What process do you want to learn the most?” In this chapter you will learn how, and, as in previous chapters, I begin with a little history. Then you will learn the chemistry and sequence of the various stages to a finished print. This chapter gives you alternatives to traditional platinum/palladium chemistry and provides you with a simple sensitizer “drop chart” that is based on the type of negative you are working with, rather than the print you would like to make. I also provide the beginnings of a trouble-shooting list to assist in hunting down problems that may be showing up in your work. Finally, you’ll get some brief alternative ideas for combining platinum/palladium with other techniques such as Van Dyke and gum bichromate. A LITTLE HISTORY Like most refined non-silver and alternative photographic processes, the art of platinum/palladium printing was developed in pieces over time by a number of dedicated artists and scientists. In 1830, Ferdinand Gehlen recorded the action and effects of light on platinum chloride, noting that UV light would alter the color of platinum salts and cause the ferric salts to precipitate out into a ferrous state. At around the same time, Johann Wolfgang Dobereiner (1780–1849) observed the decomposition of ferric oxalate on exposure to UV light and scientifically defined its sensitivity.
    [Show full text]
  • Copper Alloys
    THE COPPER ADVANTAGE A Guide to Working With Copper and Copper Alloys www.antimicrobialcopper.com CONTENTS I. Introduction ............................. 3 PREFACE Conductivity .....................................4 Strength ..........................................4 The information in this guide includes an overview of the well- Formability ......................................4 known physical, mechanical and chemical properties of copper, Joining ...........................................4 as well as more recent scientific findings that show copper has Corrosion ........................................4 an intrinsic antimicrobial property. Working and finishing Copper is Antimicrobial ....................... 4 techniques, alloy families, coloration and other attributes are addressed, illustrating that copper and its alloys are so Color ..............................................5 adaptable that they can be used in a multitude of applications Copper Alloy Families .......................... 5 in almost every industry, from door handles to electrical circuitry to heat exchangers. II. Physical Properties ..................... 8 Copper’s malleability, machinability and conductivity have Properties ....................................... 8 made it a longtime favorite metal of manufacturers and Electrical & Thermal Conductivity ........... 8 engineers, but it is its antimicrobial property that will extend that popularity into the future. This guide describes that property and illustrates how it can benefit everything from III. Mechanical
    [Show full text]
  • Advertising Platinum Jewelry
    FTC FACTS for Business Advertising Platinum Jewelry ftc.gov The Federal Trade Commission’s (FTC’s) Jewelry Guides describe how to accurately mark and advertise the platinum content of the jewelry you market or sell. Platinum jewelry can be alloyed with other metals: either precious platinum group metals (PGMs) — iridium, palladium, ruthenium, rhodium, and osmium — or non-precious base metals like copper and cobalt. In recent years, manufacturers have alloyed some platinum jewelry with a larger percentage of base metals. Recent revisions to the FTC’s Jewelry Guides address the marking of jewelry made of platinum and non-precious metal alloys and when disclosures are appropriate. When Disclosures Should Be Made Product descriptions should not be misleading, and they should disclose material information to jewelry buyers. If the platinum/base metal-alloyed item you are selling does not have the properties of products that are almost pure platinum or have a very high percentage of platinum, you should disclose that to prospective buyers. They may want to know about the value of the product as well as its durability, luster, density, scratch resistance, tarnish resistance, its ability to be resized or repaired, how well it retains precious metal over time, and whether it’s hypoallergenic. You may claim your product has these properties only if you have competent and reliable scientific evidence that your product — that has been alloyed with 15 to 50 percent non-precious or base metals — doesn’t differ in a material way from a product that is 85 percent or more pure platinum. Facts for Business Terms Used in Advertising • Jewelry that has 850 parts per thousand pure platinum — meaning that it is 85 percent pure • Any item that is less than 500 parts per platinum and 15 percent other metals — may be thousand pure platinum should not be marked referred to as “traditional platinum.” The other or described as platinum even if you modify the metals can include either PGMs or non-precious term by adding the piece’s platinum content in base metals.
    [Show full text]
  • 1 an Investigation of the Mechanical and Physical Properties of Copper
    An Investigation of the Mechanical and Physical Properties of Copper-Silver Alloys and the Use of These Alloys in Pre-Columbian America by Shannon L. Taylor Submitted to the Department of Materials Science and Engineering in Partial Fulfillment of the Requirements for the Degree of Bachelor of Science at the Massachusetts Institute of Technology June 2013 © Massachusetts Institute of Technology. All rights reserved. Signature of Author: ____________________________________________________________ Department of Materials Science and Engineering May 3, 2013 Certified by: ___________________________________________________________________ Heather Lechtman Professor of Archaeology and Ancient Technology Thesis Supervisor Accepted by: __________________________________________________________________ Jeffrey Grossman Carl Richard Soderberg Associate Professor of Power Engineering Chair, Undergraduate Committee 1 An Investigation of the Mechanical and Physical Properties of Copper-Silver Alloys and the Use of These Alloys in Pre-Columbian America by Shannon L. Taylor Submitted to the Department of Materials Science and Engineering on May 3, 2013 in Partial Fulfillment of the Requirements for the Degree of Bachelor of Science in Archaeology and Materials ABSTRACT In both the Andean zone of South America and in Mesoamerica, copper-silver alloys were important in the production of thin, silver-colored sheet metal artifacts. This thesis examines the mechanical and physical properties of the copper-silver alloy system that are important to understanding why copper-silver alloys became central to the metallurgies that developed among prehistoric societies of the Andean zone and Western Mexico. These properties include their range of malleability, the microstructures behind their toughness, and the recrystallization and annealing behaviors that led to their development of silver-enriched surfaces. To determine these properties, a series of cold rolling, cold hammering, and annealing experiments were performed on five Cu-Ag alloys and pure copper.
    [Show full text]
  • JD: Jewelry Design
    JD: Jewelry Design JD 101 — Introduction to Jewelry JD 115 — Metal Forming Techniques: Fabrication Chasing and Repousse 2 credits; 1 lecture and 2 lab hours 1.5 credits; 3 lab hours Basic processes used in the design and Introduces students to jewelry-forming creation of jewelry. Students fabricate their techniques by making their own dapping own designs in the studio. and chasing tools by means of forging, JD 102 — Enameling Techniques for annealing, and tempering. Using these Precious Metals/Fine Jewelry/Objects tools, objects are created by repousse and D'Art other methods. 2 credits; 1 lecture and 2 lab hours Prerequisite(s): all first-semester Jewelry Vitreous enameling on precious metals. Design courses or approval of chairperson Studies include an emphasis on the "Co-requisite(s): JD 116, JD 122, JD metallurgical properties of gold, silver, and 134, JD 171, and JD 173 or approval of platinum and their chemical compatibility chairperson. with enamels. Surface treatments, ancient JD 117 — Enameling for Contemporary and modern, that intensify the jewel- Jewelry like qualities of vitreous enamel on 2 credits; 1 lecture and 2 lab hours precious metal will be explored. along with Vitreous enamel has been used for construction techniques that help students centuries as a means of adding color transform glass into beautiful, functional and richness to precious objects and jewelry and objects of art. jewelry. This course examines historical Prerequisite(s): JD 101. and contemporary uses of enamel, and JD 103 — Jewelry and Accessories explores the various methods of its Fabrication (Interdisciplinary) application, including cloisonne, limoges 2 credits; 1 lecture and 2 lab hours and champleve, the use of silver and gold This is an interdisciplinary course cross- foils, oxidation, surface finishing and setting listed with LD 103.
    [Show full text]
  • Platinum, Silver- Platinum, and Palladium Prints
    Noble Metals for the Early Modern Era: Platinum, Silver- Platinum, and Palladium Prints Constance Mc Cabe Histories of photography usually emphasize the photogra- phers’ command of the camera and the resulting pictures while offering little insight into the extensive chemical and technical artistry performed in studios and darkrooms. Research into the materials and methods behind photo- graphic prints, however, can shed light on the aesthetic goals of the photographers and help to determine which properties are the result of artistic decisions and which might be the natural effects of aging. By studying the array of platinum, silver- platinum, and palladium prints in the Thomas Walther Collection, we are given an opportunity to appreciate how photographers in the early twentieth cen- tury manipulated materials and chemicals to achieve a quasi-modern aesthetic. The aesthetic benchmark for many photographers at the dawn of the twentieth century was the platinum print, extolled for its unparalleled artistic qualities and perma- nence. Alfred Stieglitz (1864–​­1946) and Clarence H. White (1871–​­1925), both highly influential photographers and lead- ers of Pictorialism, a movement championing photography as fine art, praised platinum as the ideal photographic medium for their exhibition prints. Their disciples contin- ued to test the medium for new and unusual effects, exploiting such curiosities as multiple exposures, tone reversal, and solarization, and exploring unconventional compositional elements and abstraction. Highly attuned to the technical craft of their work, they investigated myriad products and chemical modifications to achieve their artistic fig. 1 Alfred Stieglitz. From the Back Window at “291”. April 3, 1915. Platinum print, objectives.
    [Show full text]
  • The Effect of Copper on Crevice Corrosion of Stainless Steels
    MATERIALS SELECTION & DESIGN The Effect of Copper on Crevice Corrosion of Stainless Steels ROGER FRANCIS, FNACE, RFMaterials, Crevice corrosion leaks on super­ Examination and Testing Glossop, Derbyshire, United Kingdom duplex stainless steel sprinkler heads An initial examination of the S32760 GLENN BYRNE, Rolled Alloys, Blackburn, occurred in a firewater sprinkler sys­ sprinkler heads showed severe crevice cor- Lancashire, United Kingdom tem operating at 22 °C. Tests showed rosion of the threads, despite the relatively that copper deposits from corroding low temperature in the accommodation copper alloys could act as very effi­ module. Just outside the creviced area, cient cathodes and stimulate dissolu­ coppery-colored deposits were clearly visi- tion during the regular breakdown ble. It was thought that these deposits might have originated from the reduction and repassivation of the passive film of soluble copper corrosion products in crevices. Several other service fail­ formed during the corrosion of the bronze ures have occurred because of a simi­ sprinkler heads. lar mechanism, which had not been To determine whether this was possi- previously reported. ble, 50-mm square plates (3-mm thick) were fitted with polyacetal crevice washers, as described in ASTM G78.2 The washers Superduplex stainless steels (SS) such as were loaded with nylon-coated disc springs UNS S32760 and UNS S32750 have been to produce a load of 27 N/mm2, which pro- widely used in seawater systems because of vided a tight crevice similar to that found their excellent resistance to crevice corro- in a screwed joint. The samples were sion. Reviews of service experience have immersed in synthetic seawater containing shown satisfactory performance with Alloy 50-mg/L cupric ions at 20 °C and the water Z100 (UNS S32760) up to ~40 °C.1 was continuously aerated with compressed In the late 1990s, there were some air.
    [Show full text]
  • The Platinum Group Metals As Coating Materials
    Issue No. 38 – February 2012 Updated from Original August 2002 Publication The Platinum Group Metals as Coating Materials How precious is your metal - An overview on The platinum group metals consist of platinum and palladium, as well as rhodium, iridium, the use of the platinum osmium, and ruthenium. They can be found in the transition metals on the periodic table of the elements. A close-up of this part of the table is shown in Figure 1. Palladium is currently the group metals as contact surfaces for electronic only metal of the group in widespread use in electrical contacts, although platinum was widely connectors. used in the past. Rhodium is only used in electrical contact applications requiring very high hardness and wear resistance. The other three metals in the group are used mainly in other industrial applications. Pure, electroplated platinum and palladium have a hardness of around 200 to 400 HV, although . Platinum they may also be applied by cladding. Both have a conductivity of around 16% IACS. Thus they are harder than gold, but slightly less conductive. At one time, their prices were . Palladium competitive with gold, and gold-flashed palladium coatings were even used as less expensive alternatives to gold coatings. However, both of these metals are much more expensive than gold . Rhodium (at least at the time of this writing). Due to its cost, gold-flashed palladium is now used mainly in applications which require greater hardness and wear resistance than hard gold alone. Ruthenium Rhodium is much harder than platinum and palladium, typically 800-1000 HV, with an .
    [Show full text]
  • Copper Tungsten
    REFRACTORY METALS Grade RWMA Type Density Electrical Rockwell Ultimate Cross Break Group B Gm./cc Cond. % Hardness Strength Strength IACS PSI PSI T-1W Class 10 12.6 53 - 60 72 - 82-B 63,000 110,000 T-3W Copper 13.93 48 - 53 85 - 92-B 75,000 130,000 T-5W Tungsten 14.18 46 - 52 88 - 95-B 85,000 140,000 T-10W Class 11 14.8 42 - 50 94 - 100-B 90,000 150,000 T-20W Class 12 15.12 41 - 52 98 - 107-B 95,000 160,000 T-30W 15.6 41 - 49 98 - 106-B 100,000 158,000 T-3W53 * Copper Alloy 13.5 28 - 32 101 - 106-B 120,000 180,000 T-10W53 * Tungsten 14.6 26 - 30 105 - 110-B 160,000 200,000 T-TC5 Copper Tungsten 11.27 42 - 50 90 - 100-B 70,000 140,000 T-TC10 Carbide 11.64 38 - 45 97 - 108-B 75,000 160,000 T-TC20 12.7 27 - 35 34 - 40-C 85,000 180,000 T-TC53 * Copper Alloy 12.6 18 - 23 40 - 50-C 150,000 220,000 Tungsten Carbide T-G12 Silver Tungsten 11.8 50 - 60 50 - 65-B 35,000 65,000 T-G13 Carbide 12.2 45 - 55 70 - 85-B 40,000 90,000 T-G14 13.1 30 - 40 95 - 105-B 55,000 120,000 T-G17 Silver 10.1 45 - 50 80 - 90-B 60,000 135,000 T-G18 Molybdenum 10.2 50 - 55 70 - 80-B 45,000 110,000 T-20S Silver Tungsten 48 - 53 90 - 100-B 70,000 130,000 T-35S 50 - 56 80 - 87-B 50,000 120,000 T-100W Class 13 Tungsten 19.28 31 35 - 50-C 100,000 - T-100M Class 14 Molybdenum 10.2 32 88 - 98-B 100,000 - * Properties listed are those of fully heat treated material.
    [Show full text]