LECTURE PRESENTATION

Reading Assignment

• 35.1 Introduction to Surface Engineering

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Metal Finishing Guidebook

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