5:32 pm | January 15, 2012
Author: ManufacturingET.org | Category: | Comments: None
Reading Assignment
- 35.1 Introduction to Surface Engineering
- 35.2 Mechanical CLeaning and Finishing
- 35.3 Chemical Cleaning
- 35.4 Coatings
- 35.5 Vaporized Metal Coatings
- 35.6 Clad Materials
- 35.7 Textured Surfaces
- 35.8 Coil-Coated Sheets
- 35.9 Edge Finishing and Burrs
- 35.10 Surface Integrity
Outline
Importance of Surface Condition
- Friction
- Fit
- Aesthetic
- Corrosion resistance
- Fatigue strength
Surface Topography
ASME Y 14.36M – 1996
- Roughness Rt and Ra – Finely spaced irregularities
- Waviness – Greater spacing than roughness.
- Lay – Direction of surface patterns
- Cutoff – Sampling length used in the calculation of roughness. If not specified, a value of .030 in. is assumed.
Typical Values of Roughness
Mechanical Cleaning and Finishing
Blast Cleaning
Barrel Finishing or Tumbling
Vibratory Finishing
Abrasive Flow (video)
Media
Natural abrasives
slag, cinders, sand, granite chips, limestone hardwood
Synthetic
Aluminum oxide, silicon carbide embeded in a binder
Compounds
Added to media and workpieces.
- Liquid or dry
- Abrasive or nonabrasive
- Acid, alkaline, or neutral pH
- Assist deburring, burnishing and abrasive cutting
- Provide cleaning, descaling, or corrosion inhibition
- Enhance color, and brightness
Belt Sanding
Wire Brushing
Buffing
Electropolishing
Reverse of electroplating
Removes material from raised surfaces first
Chemical Cleaning
Alkaline
Solvent
Vapor Degreasing
contaminants stay in the solvent bath
not environmentally friendly
Ultrasonic Cleaning
Acid Pickling
Sulfuric or Muriatic (hydrochloric) acid used to remove oxides acid
Passivation
Nitric acid passivation
Citric acid passivation
