In 2008, The US Environmental Protection Agency (EPA) registered copper alloys as an antimicrobial material and approved a number of public health claims related to copper’s ability to kill specific bacteria. One of these claims stated that when cleaned regularly, antimicrobial copper alloy surfaces would kill more than 99.9% of bacteria within 2 hours, and continue to kill more than 99% of bacteria even after repeated contamination. The ancient Egyptians used copper in various forms to sterilize wounds and preserve drinking water, and interest in the medicinal value of the material continued for generations. Interest and use dropped markedly in the 1930s, however, with the development of medicinal antibiotics. Recently, antibioticâ€�resistant bacteria have emerged, and the benefits of copper are again being recognized.
- Use the Internet or other information source to identify some of the health�related applications that are now emerging for copper and copper alloys. Select one such application and summarize its benefits.
- What might be some of the deterrents or limitations to the use of copper and copper alloys, or the conversion to them from other materials, such as stainless steel?
Want to see the full answer?
Check out a sample textbook solutionChapter 7 Solutions
Degarmo's Materials And Processes In Manufacturing
- Explain how the properties and structure of different given engineering materials affect their behaviour in given engineering applications 1) Machinery such as farm equipment and packaging machines uses shear pins made from high carbon steel to prevent overload if something becomes jammed. Explain the reasons for choosing this material. 2) Titanium alloy (code Ti-6Al-2Sn-4Zr-6Mo) is widely used for aircraft engine components and chemical plant equipment. Explain why it performs well in conditions of high stress and high temperature. For each answer you must explain how the properties and structure of the material affect its performance. - include diagrams if appropriatearrow_forwardUse a E-p chart to identify metals with both E> 100 GPa and E/p> 0.02 GPa/(kg/m3). Show your answer with a sketch on the selection chart. Young's modulus, E (GPa) 1000 100 10-1 10-2 10-3 10-4 10 Young's modulus - Density Foams Fugid polymer Toams Composites CFRP Natural P materials 100 Flexible polymer foams Technical ceramics Wood grain Cork Mg aloys GFRP EVA leoprene nucber hyester O 583 Concrele Al₂O₂ 1000 Density, p (kg/m³) Ti allbys Zinc alloys PEEK PET 'Nón-technical Epodes ceramics PC PTFE Polymers Silicone Gastomers syunting prene Naloys Elastomers WC Ov-Walbys Cu alloys Metals Lead allbys 10,000 Guide lines for minimum mass designarrow_forwardCopper and copper alloys as specified by the Copper Development Association (CDA) and are designated as C00001 thru C99999 in the Unified Numbering System (UNS). True False An alloy steel designated as AISI 4130 WQT 700 means: chromium-molybdenum alloy steel containing .30% carbon in solution, that is through heat treated and water quenched. True False An AISI 4340 alloy steel contains .43 percent or 43 points of the element carbon in solution. True False Chemicals from which the commercially important plastic resins are derived are themselves derived from natural products that are quite plentiful; these raw materials include coal, water, limestone, sulfur, salt, and petroleum. True False There are two (2) types of polymerization; addition or linear and cross-linked or condensation. Addition polymers are thermoplastics and cross-linked polymers are thermosetting materials. True Falsearrow_forward
- As an R&D engineer, your input is requested to design an enhanced device that will be permanently implanted to repair the load-bearing function of a joint. Details on the candidate metals are presented here: Material SS 316 type Pure Ti Density (p) Yield stress (g/cm³) (MPa) 8 4.5 Ti6A14V 4 (F136) 190 140 795 Maximum elongation (%) 40 15 10 Elastic modulus (GPa) 190 110 114 Lo Shess leve O What force can each of the materials carry without permanent deformation? Which one offers better properties as a load-bearing implant? Explain. Describe the primary consequences of choosing the wrong material; consider in your answer the effect of density, yield stress, elongation, and Young's modulus on the implant's performance.arrow_forwardIdentify which of the two materials will become negatively charged if charged by friction. Write your answer in phrase. 1. Wool or PVC 2.Paper or plastic cover 3. Cotton or glass 4. fur or wood 5. Gold or silkarrow_forwardAn engineer works in an automobile company where engines are designed. You are asked to design brass-based pistons which will slide into steel cylinders. The engine in which the pistons will be used will operate between 20 ° C and 150 ° C. A. If the engine reaches a temperature of 150 ° C and the diameter of the pistons at 20 ° C is 25,000 cm, what minimum diameter should the cylinders initially have for the pistons to operate correctly, that is, not to bind? (Work with 5 significant figures) take the following into account: ?laton=2,0×10-5(℃)-1 , ?acero=1,2×10-5(℃)-1arrow_forward
- We wish to produce an 0.3 inch plate of oxygen-free, high-conductivity (OFHC) copper that has a yield strength of at least 45 ksi and elongation of at least 10%. The original thickness of the plate is 3 inches. The width of the plate remains the same during processing. Which of the following procedures would give the correct final properties. More than one answer is possible. Group of answer choices Hot work from 3 to 0.5 inches; cold work from 0.5 to 0.3 inches Cold work from 3 to 1 inch; cold work from 1 to 0.5 inches; hot work from 0.5 to 0.3 inches Cold work from 3 to 1 inch; cold work from 1 to 0.4 inches; cold work from 0.4 to 0.3 inches Cold work from 3 to 1 inch; do full anneal; cold work from 1 to 0.5 inches; do full anneal; cold work from 0.5 to 0.3 inches Hot work from 3 to 0.4 inches; cold work from 0.4 to 0.3 inches None of the above will work Cold work from 3 to 0.3 inches Cold work from 3 to 1 inch; hot work from 1 to 0.4 inches; cold work from 0.4…arrow_forwardWhat are the different types of corrosion in mechanical engineering and how are they classified?arrow_forward8. Please select the correct answer: (a) These materials have a negative magnetic susceptibility, and when are placed in a magnetic field, develop a magnetization vector in the opposite direction to the applied field (b) These materials have a positive and very large magnetic susceptibility, and may have large permanent magnetizations even in the absence of an applied magnetic field. (c) These materials have a small positive magnetic susceptibility, and when are placed in a magnetic field, develop a magnetization vector along the direction of the applied field. (I) Paramagnetic (II) Ferromagnetic (III) Ferrimagnetic (IV) Diamagneticarrow_forward
- Question 1 You are working on a design team at a small orthopaedic firm. You have been asked to select a cobalt- chrome-molybdenum (CoCr) material that will not experience plastic deformation under a specific mechanical test, as follows... A tensile stress is applied along the long axis of a solid cylindrical rod that has a diameter of 10 mm. An applied load of some magnitude F produces a 7x10³ mm change in diameter (see figure below, original shape is blue, elongated shape is unshaded). Q1H: Provide a brief rationale based on calculations used to support your answer. That is, how would you explain the behavior of the "new alloy" material to your design team? Table of properties: Assume Poisson's ratio is 0.3 for all materials Process Elastic Modulus (GPa) Material CoCr F75 As cast/Annealed 210 CoCr F90 Hot forged New alloy Z X ↑ F df O 210 110 Yield Strength (MPa) 450-517 900-1200 600 Tensile Strength (MPa) 655-890 1400-1600 700arrow_forwardQuestion 1 You are working on a design team at a small orthopaedic firm. You have been asked to select a cobalt- chrome-molybdenum (CoCr) material that will not experience plastic deformation under a specific mechanical test, as follows... A tensile stress is applied along the long axis of a solid cylindrical rod that has a diameter of 10 mm. An applied load of some magnitude F produces a 7x10³ mm change in diameter (see figure below, original shape is blue, elongated shape is unshaded). Q1C-D: Using the table of material properties below, calculate the magnitude of stress (o) and applied load (F) required to produce the 7x10-³ mm change in diameter for rods fabricated from F75 CoCr alloy (as cast) and F90 CoCr alloy (hot forged) materials.arrow_forwardQuestion 1 You are working on a design team at a small orthopaedic firm. You have been asked to select a cobalt- chrome-molybdenum (CoCr) material that will not experience plastic deformation under a specific mechanical test, as follows... A tensile stress is applied along the long axis of a solid cylindrical rod that has a diameter of 10 mm. An applied load of some magnitude F produces a 7x10-³ mm change in diameter (see figure below, original shape is blue, elongated shape is unshaded). Q1E: Of those two materials (F75 CoCr alloy (as cast) and F90 CoCr alloy (hot forged)), which materials would you select to assure that the deformation is entirely elastic (No yield!)?arrow_forward
- Refrigeration and Air Conditioning Technology (Mi...Mechanical EngineeringISBN:9781305578296Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill JohnsonPublisher:Cengage LearningWelding: Principles and Applications (MindTap Cou...Mechanical EngineeringISBN:9781305494695Author:Larry JeffusPublisher:Cengage LearningPrecision Machining Technology (MindTap Course Li...Mechanical EngineeringISBN:9781285444543Author:Peter J. Hoffman, Eric S. Hopewell, Brian JanesPublisher:Cengage Learning