24-11-2012, 04:04 PM
METHODS TO IMPROVE WEAR RESISTANCE OF MATERIALS
METHODS TO IMPROVE WEAR.ppt (Size: 2.12 MB / Downloads: 53)
INTRODUCTION
Causes failure of machines
Reduces efficiency of machine parts
Significant maintenance
Heavy replacement costs
Leads to increase in clearances
TYPES OF WEAR
Adhesive wear
Abrasive wear
Fatigue wear
Corrosive wear
NITRIDING
Heat treatment process
Enriching the surface with the nitrogen
Conducted mainly between 450o-620o C [4]
Formation of nitrogen compounds with iron and alloying elements like Al or Cr
CARBONITRIDING
Inclusion of a nitrogen component in the form of ammonia
Economical than carburizing
Conducted at lower temperatures
Increased resistance to quenching distortion