For others related to the field the subscription rate per year, including a copy of the “Universal Metal Finishing Guide Book Issue” is: $ in the U.S., $ . Guide Book. Issue link: raudone.info . MFGB_C3 · MFGB_C4 · view archives of Metal Finishing Guide Book - Water contaminated with oil, plating solutions, cleaners, etc. are ideal NOW FOR /14 UNIVERSAL METAL FINISHING GUIDEBOOK Call for all the details.
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A. I believe that the guidebook is considered a special edition of the magazine, so I would say that a subscription is the way to download it. But you . The file name refers to the reference number, the AP42 chapter and section. The file name. "ref02_c01spdf" would mean the reference is from AP42 chapter 1. Read the latest articles of Metal Finishing at raudone.info, Elsevier's Guidebook and Directory Issue Pages 16, , , 30, View PDF.
Brush plating is useful for plating surfaces that are simply impractical or too costly to consider for treatment in conventional facilities. The process can be carried out on site, far from a plating shop and using low volumes of plating solution. If necessary, a battery or generator may be used for current. In large applications the pen is substituted for something more resembling a roller.
In modern times, complete cathedral domes have been plated using this method. A coating of uniform thickness may be applied to both sides or to one side only of the strip. Articles can be made from the precoated metal by normal fabrication procedures and frequently require no further electroplating operations.
Metal Finishing – 2012 Organic Finishing Guidebook
The best known example is the production of tinplate and its use mainly in the manufacture of containers. Continuous electroplating with other metals, such as zinc and nickel, is also well established.
The continuous plating of wire is another important industrial process.
Particular applications are tin coated copper wire of electrical use, zinc plated steel wire for ropes and hawsers, and brass coated steel wire for use in tyres. SAMFA Metal Finishing Handbook For the economical manufacture of components required by the electronics industry, reel-to-reel plating is coming into increasing use, the principal coatings applied being gold and tin-lead1.
A simple coated strip may be produced, then blanked and formed to yield the finished components. Often, however, the basis material is pre-blanked but held together at one or both edges, so that it can still be plated continuously, and possibly undergo other manufacturing stages, before being separated into individual components.
Selective plating using permanent masks, as described above, is increasingly common in reelto-reel as well as batch plating.
The particular coatings to be applied and the intended use of the finished article may also affect the choice made. The quality and adhesion of electroplated coatings are critically dependent on the surface condition of the substrate. Films and any other contaminants must be removed. Slight attack, at least, on the surface itself is generally desirable, to eliminate any disturbed outer layer and expose a clean, firm structure, but there is no need for the surface to be roughened.
Metal Finishing Techniques for Artists, Craftsman and Sculptors
The usual sequence is to clean, then to etch lightly, although some materials may suffer slight attack during cleaning. With heavily scaled components it may sometimes be necessary to clean, pickle, then clean again. Special treatments or undercoats required for particular materials will be considered later, but it is convenient first to review the general range of pre-treatment processes. Cleaning processes fall into two broad classes, alkaline and solvent-based.
Alkaline cleaning is virtually essential and although there are advantages to solvent cleaning, environmental considerations are putting pressure on 1 Tin-lead coatings will give way to lead free coatings under compliance with European RoHS legislation. Organic solvents, such as trichloroethylene and perchloroethyene, are still being used hot in vapour or liquid-vapour degreasers, but over time these installations will come under increasing scrutiny by authorities.
Inhibitors are added to the solvents to prevent their decomposition, but there are some solvent-metal combinations that must be avoided. When contaminated, the solvents may be recycled by the supplier by re-distillation and with the addition of inhibitors.
In the same way, emulsifiable solvents that have been used as soak cleaners also have been largely phased out due to the negative environmental impacts.
These solvents contain surface active agents, which cause them to be emulsified in a subsequent water rinse and so removed along with the soil. Unfortunately, the solvents leaving the factory as effluent continue to cause problems further down the line.
The most satisfactory apparent substitute for solvent cleaning at this stage is ultrasonic cleaning, making use of a suitably modified alkaline cleaning formulation. Alkaline cleaners may contain sodium hydroxide and alkaline salts such as metasilicate, carbonate, tripolyphosphate or hexametaphosphate, as well as powerful wetting and sequestering agents.
The sodium hydroxide may be omitted, however, where only a light-duty cleaner is required.
Cyanides, once included in some heavy duty formulations, are also being excluded as the industry seeks to rid itself of toxic products. The cleaners are used hot, the work being immersed for anything between one and twenty minutes depending on a permutation of variables such as the surface contamination, the solution formulation, available time, etc. Mechanical effects such as movement of the parts, the solution or both help to accelerate the process. Further acceleration can be achieved by simultaneously passing an electric current.
The gas generated on the surface of the work contributes a valuable scouring action. As there is more hydrogen liberated at a cathode the workpiece than oxygen at an anode for a given flow of current, cathodic cleaning is often preferred.
It cannot be used, however, where there is any danger of hydrogen embrittlement; and, because of the likelihood of substances being cathodically deposited on the surface, it is often followed by a brief anodic treatment occasionally, the current is reversed several times.
Brass qualifies as such a material. Cleaning is usually followed by a rinse in water, then a dip in a dilute hydrochloric or sulphuric acid solution, followed by a further rinse, before entering the plating bath.
The function of the acid dip is to neutralise the alkali remaining on the part, dissolve any oxide film that might have formed and etch the surface slightly. Sometimes the acid dip is replaced by an electrolytic acid etch. After rinsing, the parts are given a brief dip in dilute acid solution, then rinsed twice before being placed in the plating tank. Where there is any question of adhesion being compromised, for example through potential incomplete removal of welding scale an anodic etch in sulphuric acid solution may replace or complement the acid dip.
A similar procedure is used for cast iron, but it is important in this case to etch a high current density for only a short time. In a manual operation it may then be necessary to brush away any loose carbon and re-immerse briefly in the etch solution without current.
In automatic and semi-automatic plants an alkaline electroclean is introduced following such an acid electro-etch harnessing the hydrogen scrubbing effect to brush away any loose carbon that forms.
Organic Finishing Guidebook & Directory
High-carbon steels are prone to hydrogen embrittlement and cleaning steps involving the generation of hydrogen should be avoided or strictly limited. Hardened steels should, if possible, be stress relieved by heat treatment before plating. Preparation for plating is otherwise similar to that recommended for low-carbon steels, except that an electrolytic etch is recommended; it is sometimes preceded by an acid dip and anodic electroclean to remove smuts , with intermediate rinses.
These steels should be heat treated as soon as possible after electroplating in order to relieve hydrogen embrittlement. High-alloy steels including stainless steels require very thorough cleaning and etching, following the same procedure as described above, but care is necessary to ensure that too much attack on chromium-containing alloys does not occur in the anodic cleaner.
It is not sufficient, however, after the sulphuric acid etch, simply to rinse and then plate, as an oxide film develops very rapidly Section 1 - Electroplating once the etch solution is removed from the surface.
The difficulty is overcome by the use of a 'strike' solution. This is a plating solution that is strongly acid and contains a rather low concentration of depositable metal ions.
When the work is made cathodic in this solution, copious evolution of hydrogen occurs. This, in combination with the acid present, rapidly removes any residual oxide film; meanwhile metal is slowly deposited on the freshly exposed surface.
After a few minutes, the work can be transferred directly, without rinsing, to the main plating tank. The most popular strike solutions, for use before plating in a nickel bath, contain either nickel chloride and hydrochloric acid or nickel sulphate and sulphuric acid. A somewhat more elaborate sequence may be followed with engineering applications when manually preparing components such as complex machined castings and the like.
For example, the work may be scrubbed with pumice after cathodic cleaning, and the formulation of the acid dip may be varied. The sequence for beryllium copper is specialised. Several methods have been used. A suggested sequence is; soak clean is a suitably formulated alkaline degreaser, rinse, pickle in an ambient sulphuric-peroxide mixture, electro-strike in a basic copper sulfate solution containing no additive or brighteners, and then proceed to the next plating step.
The reason for employing an acid strike is because beryllium forms insoluble salts with the cyanide copper strike most commonly used. The castings are often plated with decorative coatings of nickel plus chromium or other decorative top coats, but an undercoat of copper is almost always present.
In preparing zinc die castings for plating, it must be borne in mind that the alloy is readily attacked by both acid and alkaline solutions. Fortunately, the material straight from the mould is generally very clean and does not require aggressive cleaning.
Gold Refining Forum.com
Click on the link, wait a few seconds for the first page to appear, and hover over the pdf icon at the top. Two icons drop down. Click on the right one to download the entire book. They keep changing the MF site and this is the first time in a long time I've seen that you could download the book.
It's basically the plater's bible but there's a lot of valuable stuff for refiners also. There are chapters on such things as stripping plated coatings, analysis, power supplies, fume control, waste control, etc.
I have 2 hard copies of it and use them at least once a week for refining purposes. Preview Unable to display preview.
Blacksmith seeking primer on Metal Finishes
Download preview PDF. Further Reading 1. Greef, R. Peat, L. Peter, D. Pletcher and J. Google Scholar 2. Bockris and G. CrossRef Google Scholar 3. Lowenheim Ed. Google Scholar 4.That link obviously will not work forever, but is still working this month, so download a soft copy while you're waiting for your used copy to arrive. These were unreliable devices occupying too much booth space affecting the efficiency of powder collection.
In automatic and semi-automatic plants an alkaline electroclean is introduced following such an acid electro-etch harnessing the hydrogen scrubbing effect to brush away any loose carbon that forms. The company is also presenting the acid-resistant, super durable Premier XAR for use in powder coatings. Also, the chapter on Stripping Metallic Coatings has been eliminated. Even a uniform coating thickness, t, applied to an external screw thread, increases its effective diameter by about 4t, given a typical angle between the flanks of the thread.