Seminar Overview

General Information

Metal Coating Process Corporation offers periodic seminars entitled, “Principles of Electropolishing” as a service to its current and developing industrial customers. These educational sessions are held periodically at our offices in the Charlotte, North Carolina area and admission is by invitation only.

Overview of Seminar

Electropolishing has become one of the premier methods of finishing stainless steel for all medical, dental, pharmaceutical, semiconductor and related applications requiring a clean, sanitary surface. The process is capable of producing a technically superior surface, essentially featureless, with enhanced corrosion resistance.

The finish produced is unlike that obtained by mechanical finishing methods. Iron and nickel are preferentially removed, leaving a surface film consisting essentially of chromium oxide.

The electropolishing process has been available for more than fifty years, but emerging applications require constant improvements in the product, in the processing methods for maximizing product performance, and in quality control systems designed to meet the most demanding international standards.

The MCP seminar addresses these important concepts, providing a compact forum for presentation and discussion of electropolishing methods. Emphasis is placed on a basic understanding of the nature of the process, the properties of the product, and the manufacturing and quality methods required to maximize the benefits of the process.

What is Electropolishing?

Electropolishing is an electrochemical method of smoothing and brightening a metal surface. The part to be polished is connected to the positive terminal of a DC electrical system and is submerged in an electrolytic bath. The flow of current causes burrs and other surface imperfections to dissolve in the bath, producing simultaneous removal of the work-hardened surface and regeneration of an impervious oxide layer.

•	To recognize and to fully understand the advantages and disadvantages of electropolishing as a surface finishing method for stainless steel.
•	To grasp the theory of the process and to study its application to industrial problems.
•	To understand the mechanism by which the phenomenon proceeds.
•	Develop knowledge of the equipment needed for top quality electropolished finishes and for peripheral operations such as waste water treatment and ventilation.
•	To understand the preparatory methods for production of top quality electropolished surfaces.
•	To develop a basic understanding of the racking principles for electropolishing parts.
•	To learn the interaction of the basic control parameters governing the performance of the bath and the quality of the product.
•	To review new methods of determining product quality.
•	To understand the principles of ISO 9000 standards and their application to an electropolishing process.
•	To learn the use of troubleshooting techniques in the operation of an electropolishing system.
•	To understand the types of electrolyte for polishing stainless steel, and to learn optimum control methods for each type of bath.
•	To review a variety of industrial applications and to develop a broad understanding of the benefits of electropolishing.

Who should attend

The MCP Seminar will be beneficial to all employees responsible for any aspects of company activity related to electropolishing, whether their functions are Process or Product Engineering, Manufacturing, Quality Control, Purchasing, Sales, or Management. Manufacturing supervisors will appreciate the insights into the new technology of the process. Engineers responsible for product design or for specifying the performance and properties of an electropolished surface will develop an understanding of the functional nature of the finish. Purchasing personnel responsible for buying finished parts or job services will develop new tools for specifying and monitoring supplier performance. Quality control personnel will learn how to relate ISO and Total Quality Management techniques to the electropolishing process. Corporate managers will learn the capabilities of the system and will be provided with tools for planning or redesigning process facilities. Plant engineering managers will learn cost effective methods of dealing with new environmental regulations. Sales and marketing personnel will develop an appreciation for the technical characteristics of the electropolished finish and will gain new insights into marketing techniques to maximize sales.

Special Topics

Seminars can be tailored to include special topics related to tube or tank polishing applications. Several advanced seminars on topics are also available. The basic program “Principles of Electropolishing” is a prerequisite” for the advanced seminars.

Coarse Outline

Overview

• What is electropolishing?

• How is electropolishing done?

• What equipment is needed?

• Micropolishing & macropolishing

• Basic chemistry & electropolishing

Practical Applications

• Decorative

• Functional

• High Technology

Equipment for Electropolishing

• Parts on racks

• Barrel processing

• Tube methods

• Internal Cathodes

• Inductive Polishing

• Vessel Polishing

• Handheld tools for electropolishing

Pretreatment for Electropolishing

Mechanical Preparation

• Machining techniques

• Surface Grinding

• Buffing/Polishing

• Lapping

• Surface evaluation

Fundamentals of Electropolishing

• History of electropolishing

• The Bielby Layer

• Metal matrix reactions

• The anodic film (the gold layer)

• The characterization curve

• The operating range

• Voltage-amperage

• Relationships

• Material Balances

• Battelle electrolytes

• Troubleshooting

• Rules of Thumb

• Types of rectifiers

• Alkaline cleaning

• Rinsing

• Deoxidizing

• Vapor degreasing

Post-Treatment

• Nitric acid rinsing

• Removal of residual salts

• Deionized water rinses

• Drying

• Heat treatment after electropolishing

Selection of Alloys for Electropolishing

• Effect of occluded impurities

• Electroslag remelt

• Vacuum arc remelt

• Vacuum induction melt

• VIMVAR stainless steels

• Rectifier selection

• Ripple factor

• Rectifier control packages

Quality Control Considerations

• System Characterization

• Key Process Variables

• Statistical Process Control

• Oxide layer characteristics

• Ratio of chromium to iron

• ESCA profiles as a measure of product quality

• Auger analysis as a measure of product quality

• Electropolishing and ISO registration

• Electropolishing and FDA validation

Waste Treatment of Electropolishing Streams

• Electrolyte Recovery

• Rinse Water Recovery

• Waste Water Minimization

• Chemical waste destruction

• Solid waste disposal

Course Materials

	Each registrant will receive a personal copy of the following MCP publications:
•	The MCP Electropolishing Process – An Overview
•	General Process Steps
•	Installation and Operations Guide
•	Fundamentals of Electropolishing
•	Process Control for Electropolishing
•	Surface Analytical Techniques
•	Selected Literature

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