Care must be taken to ensure that the surface preparation processes do not change the surface in an undesirable or in an uncontrolled manner!
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Surface Preparation- Objectives
Reproducibility?
Reproducible surface preparation, as well as the associated handling and storage techniques, are obtained by
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Surface Preparation- Specifications
What is a standard?
A standard is a document that provides requirements, specifications, guidelines or characteristics that can be used consistently to ensure that materials, products, processes or services are fit for their purpose.
Who prepare standards?
Standards are created by a wide variety of organizations (Professional societies,
Industrial or Manufacturing Associations, Governmental Agencies, Companies, and International Bodies)
ISONISTDOESAEASMEASTM-
International Organization for Standardization
National Institute of Standards and Technology
Department of Energy
Society of Automotive Engineers
American Society of Mechanical Engineers
American Society for Testing and Materials
…
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Surface Preparation- Specifications
ASTM recommended practices for cleaning various metals prior to plating process
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Surface Preparation- Requirements
Surface Preparation depends on the requirements:
The requirements range from those concerned with monolayer coverage and atomically clean surfaces, to gross cleaning such as used for fusion welding.
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Surface Preparation- Requirements
Local contamination (film or particle) can result in locally poor adhesion of a film to a surface giving pinholes in the film.
(1) Surface Modification
What is Surface modification?
- Chemical & (micro-) structural changes of the top surface by removing, adding, or activating the material to enhance the surface engineering process
- The depth of the modification depends on the requirements
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(1) Surface Modification
Surface modification can include surface treatments such as:
Care must be taken to ensure that the surface preparation processes do not change the surface in an undesirable or in an uncontrolled manner!
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(2) Cleaning Process
A “clean” surface is one that contains no significant amounts of undesirable material.
What constitutes a clean surface depends on the process and the requirements. (a) External Surface Preparation: It is conducted as
